# What is your favorite end mill and usage



## Susquatch (Aug 15, 2021)

I just broke a pricey 1/2" carbide end mill making a vise stop. I didn't think I was doing anything wrong, and the mill was not complaining, but I'd rather not do that again anytime soon.

Thankfully, the part is not ruined. I can remove the damaged section by milling the jaw clearance step at that location.

So this begs my question:

Say you are squaring up and sizing some common cold rolled steel (bar, plate, etc), what is your goto end mill size and type for general milling?

How fast do you turn it?

What feed rate do you use? Since I don't have a power feed, just a general comment here would do. Eg, very slowly or just below complaint, slowly enough so it purrs, fast enough so it buzzes, etc.

How deep are your standard cuts?
(20 thou at a crack, 30 thou, 50 thou, as deep as I need but temper my feed rate to match the depth, etc

How much of the diameter of the mill bit do you use per pass? (3/4, 1/2, 1/3, 1/4, etc).

Any and all advice and other info will be appreciated and absorbed like a hungry sponge.


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## RobinHood (Aug 15, 2021)

Here are the recommended speeds & feeds out of the SOWA tool catalogue for plain and coated carbide end mills.






For 1/2” end mills, I usually use 1200 rpm and up to 15”/min feed rate.

When side milling, the engaged length is 1.5 D max and 0.1 D depth of cut. (This info is also out of an old SOWA catalogue, for a HSCO end mill).


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## PeterT (Aug 15, 2021)

There is lots of speed & feed & DOC info on the internet like RobinHoods guidance. But stepping back a bit, if you determine you were generally in the range, breakage can happen for other overriding reasons:
- part is not secure or allowed to flex, too much part stick out and/or tool stickout, to much tooth load which flexes the part or EM, insufficient tool grip
- mill table: if traversing X, best practice is to lock Y & of course Z
- feed direction: I think already discussed but safer to conventional mill at least until finishing. Climb milling requires both rigidity & low float movement
- older mill play: leadscrew/nut float. Some of this can be minimized with table lock but movement is movement & if the tool is free to dig in can dig it feeds on itself until something give

I'm kind of fond of these roughing EMs. They are more tolerant of higher removal rates & actually easier on your older/looser/lower HP machine. Nothing wrong with carbide at all but they are more brittle so more sensitive to all the other factors.


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## Susquatch (Aug 15, 2021)

RobinHood said:


> Here are the recommended speeds & feeds out of the SOWA tool catalogue for plain and coated carbide end mills.
> 
> For 1/2” end mills, I usually use 1200 rpm and up to 15”/min feed rate.
> 
> When side milling, the engaged length is 1.5 D max and 0.1 D depth of cut. (This info is also out of an old SOWA catalogue, for a HSCO end mill).



The charts are solid gold. Thank you!

The half inch data you gave me previously fits nicely with this. All except the feed rate. "up to 15" per minute" is 1/4" per second. The upper end of that seems crazy fast to me. But maybe for surface skimming it's ok. After all, you did say "up to". Nonetheless, I think I'll stay well shy of that till I get my sailor's legs.

How much of a cut (depth and width) would you normally take per pass when squaring up stock with a 1/2" end mill?


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## YotaBota (Aug 15, 2021)

He's an interactive "feed and speed" chart from Little Machine Shop
https://littlemachineshop.com/mobile/speeds_feeds.php


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## Susquatch (Aug 15, 2021)

PeterT said:


> ....... older mill play: leadscrew/nut float. Some of this can be minimized with table lock but movement is movement & if the tool is free to dig in can dig it feeds on itself until something give
> 
> I'm kind of fond of these roughing EMs. They are more tolerant of higher removal rates & actually easier on your older/looser/lower HP machine. Nothing wrong with carbide at all but they are more brittle so more sensitive to all the other factors.



I suspect the worn feed screw/nut is what bit me. It doesn't seem to matter which way I feed the work, the bit wanders around more than I think is reasonable. I was unlocking the Y lock to take a corner and mill in the Y direction when it happened. My guess is that the end mill took a bigger gulp of material than it could handle when I did that. Not only did the bit break, but there was a pretty darn big bite (about a 16th or so) that didn't finish getting removed. My table has just over a tenth of an inch free play on both axis. I have tried to figure out how the table could have accumulated that much freeplay to "let loose" when changing directions, but am left empty handed. In my mind, it should not have grabbed, it should have walked away. That's why I'm wondering about the depth and width of a normal cut. I am suspicious that I was cutting too wide and that generated some endplay movement that wouldn't happen with a cut less than 1/2 the width of the bit.

I've become pretty darn good at doing precision work with my lathe. But I am finding that a lot of it doesn't translate well to the mill.

I do like your idea of using a roughing bit for the rough work. I'm not sure how that plays out on multiple parts though. Wouldn't it also double the number of setups because it adds a finish pass to everything?


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## Janger (Aug 15, 2021)

I would use HSS a lot to get your sea legs. HSS is more forgiving and slower. Mainly though if you break one it isnt a calamity like breaking a expensive carbide one. Dull cutters also are much more susceptible to breaking.


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## Janger (Aug 15, 2021)

Oh if your table moves that much the lead screws and nuts need to be checked. Make sure you are not climb milling conventional mill only.


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## YYCHM (Aug 15, 2021)

I've had the best luck with 2 flute HSS and they are the easiest to re-sharpen.


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## Janger (Aug 15, 2021)

My two goto EMs are a 1/4 4 flute carbide and a 12mm 4 flute carbide. I use them constantly. Also frequently use two different 2” facing mills with inserts. One with 5 inserts of 20 edges 10 per side donut shaped for steel. And another with aluminum inserts.


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## Janger (Aug 15, 2021)

Check out this table from toms techniques:

http://tomstechniques.com/reference/

http://tomstechniques.com/wp-content/uploads/2014/12/CuttingSpeeds.pdf

I found his videos helpful too to get started.


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## YYCHM (Aug 15, 2021)

Janger said:


> My two goto EMs are a 1/4 4 flute carbide and a 12mm 4 flute carbide. I use them constantly. Also frequently use a two different 2” facing mills with inserts. One with 5 inserts of 20 edges 10 per side donut shaped for steel. And another with aluminum inserts.



You're talking about your CNC mill correct?  Do you even have a manual mill now, I know you had maybe three over time?


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## PeterT (Aug 15, 2021)

Susquatch said:


> My table has just over a tenth of an inch free play on both axis. I have tried to figure out how the table could have accumulated that much freeplay to "let loose" when changing directions, but am left empty handed.



IMO that is a lot & needs to be dealt with. Pulling side to side like that is a good way to get a feel for slack especially if you have an indicator mounted to quantify what you are suggesting is 0.100" on both X & Y axis. Having float on both axis is double the fun because it is free to roam in an area as opposed to just a line as if only one axis had wear & the other locked. However its those temporary unlock transition moments  when you set up for another traverse (just like you described) where the surprise can bite you.

Most people phrase this effect it in terms of dial backlash, its really the same thing. Its nice if you have DRO for following test but can do as easily with DTI in spindle against a reference block edge.
- dial in-feed direction only, say 3 turns so leadscrew backlash is fully taken up, don't reverse dial direction during process
- stop dial on handy dial reference like zero
- zero the DRO/DTI at this exact same spot
- slowly reverse handwheel until DRO/DTI moves off its null position, make note of how much handwheel dial movement has occurred (yours might be close to 0.100")

Video shows the ballpark shortcut without a DTI/DRO but I like the reference method more because its more repeatable & precise for what I also recommend: Repeat this at different spots on your leadscrew like 1/3, 1/2, 2/3 table displacement positions. You may find the wear is in concentrated in the middle most used area. Good to know but doesn't usually change the strategy or remedy if excessive wear is the issue. Next you need to know if you can dial this out acceptable with leadscrew nut anti-backlash adjustment as per video, so try that first.

If the available anti-backlash has been bottomed out by years of increased adjustment, then you need to pull LS assembly to examine. If you are lucky the majority wear will be confined to the brass/bronze nut (=sacrificial wear material). But if its also the LS threads, not at all unheard of, its new leadscrew time & usually do the nut as well so they are a happy low tolerance couple. I should have mentioned the dovetail gib adjustment also factors in this, but not really. Its more a tightness of fit to dovetails & angular table float. Some people crank up the dovetail tightness so it feels stiffer & floats less, but you are not fooling the leadscrew wear if that's the issue. Worse yet table can get sticky when too tight & the cutting action can easily kick the table through its float range & nasty surprise time. Wrecked part, broke tool etc. But you If you have that adjusted the gibs OK, suspect the focus is on lead screw / nut.


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## PeterT (Aug 15, 2021)

Susquatch said:


> I've become pretty darn good at doing precision work with my lathe. But I am finding that a lot of it doesn't translate well to the mill.
> I do like your idea of using a roughing bit for the rough work. I'm not sure how that plays out on multiple parts though. Wouldn't it also double the number of setups because it adds a finish pass to everything?



A worn leadscrew / nut on a lathe manifests itself into problems similar to a mill actually. Float on a lathe means the cross slide / compound / travel can be drawn in & out of the work if allowed to roam. At minimum usually results in variable finish, variable dimensions, tool chatter.... In more tolerance specific operations like threading or especially parting off, same potential for similar WTF surprise moments.

The roughing EM is something I'd encourage to try but not a magic solution to a more fundamental machine issue. Roughers make more efficient chips for the same feed / power so generally less stress on everything. The core is thicker so more rigid, less deflection. They are reasonably priced (I only have clones). If I don't care about a parts aesthetics or fit I leave it with the little stripes resultant from side milling. Or actually liftthe table a smidge & finish pass removes a good portion of stripes. Otherwise yes, you rough with this & pop in a regular EM for finishing. So an economical strategy is if say 1/2" is your go-to EM size, nice to have the same in rougher so all the setup should be the same. just a 30 sec tool change & back in business. Finishing means measuring the part directly & adjusting the settings anyways. All EMs have tolerance +/- nominal spec. If the whole job will only take 10 minutes just use your your go to 'good' tool. But of course you will wear it faster. Its kind of an axe > saw > plane type principle to use woodworking analogy.


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## Susquatch (Aug 15, 2021)

Janger said:


> I would use HSS a lot to get your sea legs. HSS is more forgiving and slower. Mainly though if you break one it isnt a calamity like breaking a expensive carbide one. Dull cutters also are much more susceptible to breaking.



I prefer hss on my lathe. So it's easy to convince me of that. I think the only meaningful negative is that I can sharpen my hss lathe bits. I have no idea how to do that with mill tools......


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## Susquatch (Aug 15, 2021)

Janger said:


> Oh if your table moves that much the lead screws and nuts need to be checked. Make sure you are not climb milling conventional mill only.



Counterclockwise around the part from outside to inside. Right?

Preferably less than half the bit diameter at a crack. Right?


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## YYCHM (Aug 15, 2021)

Susquatch said:


> I prefer hss on my lathe. So it's easy to convince me of that. I think the only meaningful negative is that I can sharpen my hss lathe bits. I have no idea how to do that with mill tools......



https://canadianhobbymetalworkers.com/threads/end-mill-sharpening-jig-project.2444/


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## Susquatch (Aug 15, 2021)

YYCHM said:


> I've had the best luck with 2 flute HSS and they are the easiest to re-sharpen.



This I would never have guessed. I think every bit I have is four flute.

I will take your advice and get some 2 flute HSS bits.

Sharpen? You can sharpen them? Holy cow! It would be a miracle if I were able to do that right!!!


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## Susquatch (Aug 15, 2021)

Janger said:


> My two goto EMs are a 1/4 4 flute carbide and a 12mm 4 flute carbide. I use them constantly. Also frequently use two different 2” facing mills with inserts. One with 5 inserts of 20 edges 10 per side donut shaped for steel. And another with aluminum inserts.



I would have been afraid of a 1/4" end mill. But I'm willing to try it. 12mm is pretty close to 1/2.

I dunno if I'm ready for a big facing bit of any kind. But I do have a two inch fly cutter with a hss bit in it that I got in an auction lot a long time ago. I've never used it.


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## YYCHM (Aug 15, 2021)

Susquatch said:


> I would have been afraid of a 1/4" end mill. But I'm willing to try it. 12mm is pretty close to 1/2.
> 
> I dunno if I'm ready for a big facing bit of any kind. But I do have a two inch fly cutter with a hss bit in it that I got in an auction lot a long time ago. I've never used it.



Fly cutters work really well for sweeping large areas give it a go.  I can get a better finish with my fly cutter than my 1" and 2" carbide insert facing endmills.


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## Susquatch (Aug 15, 2021)

PeterT said:


> IMO that is a lot & needs to be dealt with. Pulling side to side like that is a good way to get a feel for slack especially if you have an indicator mounted to quantify what you are suggesting is 0.100" on both X & Y axis. Having float on both axis is double the fun because it is free to roam in an area as opposed to just a line as if only one axis had wear & the other locked. However its those temporary unlock transition moments  when you set up for another traverse (just like you described) where the surprise can bite you.
> 
> Most people phrase this effect it in terms of dial backlash, its really the same thing. Its nice if you have DRO for following test but can do as easily with DTI in spindle against a reference block edge.
> - dial in-feed direction only, say 3 turns so leadscrew backlash is fully taken up, don't reverse dial direction during process
> ...



I have not exhaustively checked this out. I'm still qualifying the mill before deciding which one to keep. But yes, if I keep it, the Bridgeport may need new nuts and screws. The screws themselves are both visibly worn more in the center than the ends and the backlash is correspondingly worse in the middle. (see my thread "New to me Bridgeport Mill").

I have not tried adjusting them to get some out. I had planned to do a little milling first to test the mills bones out before doing anything like that. Not big jobs - just little ones like making a mill stop and vice clamps. If I decide to keep it, that will be among the first major repair jobs I do. In fact I may even install new lead screws and nuts.

I didn't really expect to break an end mill on my first job though so maybe I should rethink that......


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## Susquatch (Aug 15, 2021)

PeterT said:


> A worn leadscrew / nut on a lathe manifests itself into problems similar to a mill actually. Float on a lathe means the cross slide / compound / travel can be drawn in & out of the work if allowed to roam. At minimum usually results in variable finish, variable dimensions, tool chatter.... In more tolerance specific operations like threading or especially parting off, same potential for similar WTF surprise moments.
> 
> The roughing EM is something I'd encourage to try but not a magic solution to a more fundamental machine issue. Roughers make more efficient chips for the same feed / power so generally less stress on everything. The core is thicker so more rigid, less deflection. They are reasonably priced (I only have clones). If I don't care about a parts aesthetics or fit I leave it with the little stripes resultant from side milling. Or actually liftthe table a smidge & finish pass removes a good portion of stripes. Otherwise yes, you rough with this & pop in a regular EM for finishing. So an economical strategy is if say 1/2" is your go-to EM size, nice to have the same in rougher so all the setup should be the same. just a 30 sec tool change & back in business. Finishing means measuring the part directly & adjusting the settings anyways. All EMs have tolerance +/- nominal spec. If the whole job will only take 10 minutes just use your your go to 'good' tool. But of course you will wear it faster. Its kind of an axe > saw > plane type principle to use woodworking analogy.



My lathe is in almost mint condition with very little backlash. But I understand your point.

FWIW, I thoroughly enjoy threading and often make my own fasteners and threaded joints both sae and metric. 

BUT, parting off is my nemesis. I absolutely HATE parting off. I usually get the first 1/4 inch or so cut fairly easily, but things grind to a halt a little further in. I hate it so much that I have been known to use a hacksaw on a slowly spinning part.....or side-by-side passes with a parting blade and a bigger cut than necessary. My favorite trick of late is the run the lathe in reverse and flip the parting blade upside down.

I appreciate what you are saying about a roughing mill not being a solution to a more fundamental problem. It may well turn out that my Bridgeport has more serious issues than I can stomach and it will be the one I sell. I wish my Hartford was running so I could compare, but it is still waiting on a fix for the timing belt.

I'll be honest, I wish I wasn't asking  silly newbie questions about milling when I really shod be fixing the machine first. But I can't really make a decision without doing a little work. And my bride is increasing the pressure to make a decision each and every day that passes.

I like your idea of swapping bits but I think you underestimate how long that will take me. That said, I'm in no rush and swapping bits is a learning experience too. I plan to add a few roughing bits to the order I will make later tonight.


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## Susquatch (Aug 15, 2021)

YYCHM said:


> https://canadianhobbymetalworkers.com/threads/end-mill-sharpening-jig-project.2444/



Looks like another priority project for my list! (Insert big happy smile here!)


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## Susquatch (Aug 15, 2021)

YYCHM said:


> Fly cutters work really well for sweeping large areas give it a go.  I can get a better finish with my fly cutter than my 1" and 2" carbide insert facing endmills.



I'm chicken. Will you come over and hold my hand?

Seriously, I am quite nervous about doing that. How deep a cut can you take with one of those? And how fast do you spin it with no fear of a HSS arrow through the heart? Maybe I'll watch a few videos first.......


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## YYCHM (Aug 15, 2021)

Susquatch said:


> I'm chicken. Will you come over and hold my hand?
> 
> Seriously, I am quite nervous about doing that. How deep a cut can you take with one of those? And how fast do you spin it with no fear of a HSS arrow through the heart? Maybe I'll watch a few videos first.......



LOL.... Use the same RPM as a normal HSS endmill and for a 2" that's pretty slow 200 RPM.  For DOC I usually just feel it out.  If the mill isn't complaining you're good.  A smaller DOC will leave a better finish.  The cool thing about them is that you can re-sharpen them just like a lathe tool.   Be forewarned..... those things throw swarf EVERYWHERE.  You may want to put a curtain around the mill when using one.


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## Tom Kitta (Aug 15, 2021)

My favorite EM is 12mm carbide. For 55hrc its 16 cad. 
80% of work is done with it. Lasts on manual machine about 1 bucket of chips - 20L worth. 

For facing I use either 2 or 3in facemills. On aluminium finish is full mirror. Very similar on steel - just touch less. I have larger FM but did not use them in a while and they are - especially 6" best on AL.


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## Susquatch (Aug 15, 2021)

YYCHM said:


> LOL.... Use the same RPM as a normal HSS endmill and for a 2" that's pretty slow 200 RPM.  For DOC I usually just feel it out.  If the mill isn't complaining you're good.  A smaller DOC will leave a better finish.  The cool thing about them is that you can re-sharpen them just like a lathe tool.   Be forewarned..... those things throw swarf EVERYWHERE.  You may want to put a curtain around the mill when using one.



OK! I'll try it.

A curtain eh! I would not have thought of that. Thanks for the heads up. They say that experience is the best teacher because she gives the test first and then the lesson. I prefer to learn from others who learned from experience. But every once in a while I plow ahead without asking and then I break something like a carbide end mill.......


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## Susquatch (Aug 15, 2021)

Tom Kitta said:


> My favorite EM is 12mm carbide. For 55hrc its 16 cad.
> 80% of work is done with it. Lasts on manual machine about 1 bucket of chips - 20L worth.
> 
> For facing I use either 2 or 3in facemills. On aluminium finish is full mirror. Very similar on steel - just touch less. I have larger FM but did not use them in a while and they are - especially 6" best on AL.



Wow. That's a great price!  Where do you get yours? And does the 12mm require a metric collet? Or does a 1/2" SAE collet fit reasonably well?


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## Janger (Aug 15, 2021)

Susquatch said:


> OK! I'll try it.
> 
> A curtain eh! I would not have thought of that. Thanks for the heads up. They say that experience is the best teacher because she gives the test first and then the lesson. I prefer to learn from others who learned from experience. But every once in a while I plow ahead without asking and then I break something like a carbide end mill.......



Grab a welding magnet and a small piece of sheet metal 12" by 6" say and use it as a movable shield.


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## Janger (Aug 15, 2021)

Susquatch said:


> Wow. That's a great price!  Where do you get yours? And does the 12mm require a metric collet? Or does a 1/2" SAE collet fit reasonably well?



Aliexpress. Tom always seems to find the cheapest sources. I buy from MZG on aliexpress often enough not as cheap as that though. And you need a metric collet. An imperial 1/2" collet is 12.7mm which is too big to grab the 12mm tool. 1/2" tool holders won't work either. Buy some metric collets as part of your order if you go that way.


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## Tom Kitta (Aug 15, 2021)

Susquatch said:


> Wow. That's a great price!  Where do you get yours? And does the 12mm require a metric collet? Or does a 1/2" SAE collet fit reasonably well?



Actually regular coated 45HRC are just 13 CAD or so. The 55 is an upgrade. I use ER32 11-12mm to hold them. 

Shipping is uber fast - like 2 weeks, max 3 weeks. They ship bulk and then Canada post priority tracked. Shipping included. 

They are LARGE supplier. They have like a catalog of 100s of carbide tools. All EM sizes up to 20mm or maybe even bigger. All hardness as well - I think to 75 or maybe 85. These are expensive through. Also 20mm is expensive even in just 55HRC.


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## Janger (Aug 15, 2021)

Tom Kitta said:


> Actually regular coated 45HRC are just 13 CAD or so. The 55 is an upgrade. I use ER32 11-12mm to hold them.
> 
> Shipping is uber fast - like 2 weeks, max 3 weeks. They ship bulk and then Canada post priority tracked. Shipping included.
> 
> They are LARGE supplier. They have like a catalog of 100s of carbide tools. All EM sizes up to 20mm or maybe even bigger. All hardness as well - I think to 75 or maybe 85. These are expensive through. Also 20mm is expensive even in just 55HRC.



who's that Tom?


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## Susquatch (Aug 15, 2021)

Janger said:


> Aliexpress. Tom always seems to find the cheapest sources. I buy from MZG on aliexpress often enough not as cheap as that though. And you need a metric collet. An imperial 1/2" collet is 12.7mm which is too big to grab the 12mm tool. 1/2" tool holders won't work either. Buy some metric collets as part of your order if you go that way.



And @Tom Kitta (I couldn't quote you for some reason this time....) 

I put together a kbc order that if placed tomorrow am will arrive on Tuesday. That's more like what I call UBER FAST!

But before I press go, I will put together an AliExpress Order to compare them. I've never used AliExpress so this will be another adventure. I'll prolly do that in the morning as my old eyes are getting heavy....... 

If I go with KBC, they sell 12mm bits with 1/2" shanks. But I suspect the reason for 12mm is price not function. In that case, a regular 1/2" bit at KBC is cheaper than the 12mm so why bother. That said, a single 12mm collet is no big deal breaker. I can't see the sense in a metric set just yet though.


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## PeterT (Aug 15, 2021)

There is nothing magic about 12mm as an EM OD so don't do cartwheels trying to get a 12mm OD x  1/2" shank sized metric cutter from KBC. Just get a 0.500" OD & you will have many more to choose from. Metric OD & Imperial shank EMs are available of course because many R8 NAm toolholders are nominal IMP. So when you really need a metric cutter you can buy one & adapt to your NAm tooling.

But that's not this discussion objective. Unlike Imperial, metric EM's are generally the same size metric shank as the cutter body. Tom is just saying he favors that nominal size & vendor. I do the same, lots of metric tooling to choose from from abroad because that is their primary unit. But metric EM means metric collet, be it R8, ER, dedicated EM holder.... etc


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## Tom Kitta (Aug 15, 2021)

The company I use for past two years or so is Azzkor For example https://www.aliexpress.com/item/32896890158.html?spm=a2g0s.9042311.0.0.5b284c4dr37Xu3

Remember you can do imperial stuff with metric EM and metric stuff with imperial EM - its just touch more work. 12mm is touch smaller then 1/2 but you can treat it as "re sharpened" 1/2". 

Prices are so good on this carbide it is hard not to go with it.


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## Susquatch (Aug 16, 2021)

PeterT said:


> There is nothing magic about 12mm as an EM OD so don't do cartwheels trying to get a 12mm OD x  1/2" shank sized metric cutter from KBC. Just get a 0.500" OD & you will have many more to choose from. Metric OD & Imperial shank EMs are available of course because many R8 NAm toolholders are nominal IMP. So when you really need a metric cutter you can buy one & adapt to your NAm tooling.
> 
> But that's not this discussion objective. Unlike Imperial, metric EM's are generally the same size metric shank as the cutter body. Tom is just saying he favors that nominal size & vendor. I do the same, lots of metric tooling to choose from from abroad because that is their primary unit. But metric EM means metric collet, be it R8, ER, dedicated EM holder.... etc



PERFECT answer. My suspicion was that the global availability of metric might reduce prices VS SAE a bit. 

For now, I'll get a few metric collets in common sizes say 6 & 12 to take advantage of spot deals. Just bought four 6mm carbide bits for $20 ($5 each) on Amazon.


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## Susquatch (Aug 16, 2021)

Tom Kitta said:


> The company I use for past two years or so is Azzkor For example https://www.aliexpress.com/item/32896890158.html?spm=a2g0s.9042311.0.0.5b284c4dr37Xu3
> 
> Remember you can do imperial stuff with metric EM and metric stuff with imperial EM - its just touch more work. 12mm is touch smaller then 1/2 but you can treat it as "re sharpened" 1/2".
> 
> Prices are so good on this carbide it is hard not to go with it.



Agreed, and thanks for the link. 

I just need to make sure I don't keep breaking them! LOL!


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## Proxule (Aug 16, 2021)

YotaBota said:


> He's an interactive "feed and speed" chart from Little Machine Shop
> https://littlemachineshop.com/mobile/speeds_feeds.php


I use this too


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## Susquatch (Aug 16, 2021)

Tom Kitta said:


> The company I use for past two years or so is Azzkor For example https://www.aliexpress.com/item/32896890158.html?spm=a2g0s.9042311.0.0.5b284c4dr37Xu3
> 
> Remember you can do imperial stuff with metric EM and metric stuff with imperial EM - its just touch more work. 12mm is touch smaller then 1/2 but you can treat it as "re sharpened" 1/2".
> 
> Prices are so good on this carbide it is hard not to go with it.



I opened an AliExpress account and tried to purchase some Azzkor bits from your link. I'll be honest, I can't figure out what I'm getting, what size, or even how many. Scrolling right and left on the product images doesn't help clear things up. Maybe I am trying to hard,.... Or maybe not hard enough. Right now I'm frustrated. I plan to try again in the morning. 

I also looked for some HSS bits and failed at that too.  I'd like to give AliExpress a decent try, but they are not making it easy.


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## YYCHM (Aug 16, 2021)

Susquatch said:


> I opened an AliExpress account and tried to purchase some Azzkor bits from your link. I'll be honest, I can't figure out what I'm getting, what size, or even how many. Scrolling right and left on the product images doesn't help clear things up. Maybe I am trying to hard,.... Or maybe not hard enough. Right now I'm frustrated. I plan to try again in the morning.
> 
> I also looked for some HSS bits and failed at that too.  I'd like to give AliExpress a decent try, but they are not making it easy.



It's not you.  AliExpress is strange and a bit deceiving actually.  I had a hard time getting my head around the presentation initially.  When I ordered my first DRO I really wasn't sure what I had purchased until it arrived.

Can you provide a link to the page you're looking at.


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## DPittman (Aug 16, 2021)

Susquatch said:


> I opened an AliExpress account and tried to purchase some Azzkor bits from your link. I'll be honest, I can't figure out what I'm getting, what size, or even how many. Scrolling right and left on the product images doesn't help clear things up. Maybe I am trying to hard,.... Or maybe not hard enough. Right now I'm frustrated. I plan to try again in the morning.
> 
> I also looked for some HSS bits and failed at that too.  I'd like to give AliExpress a decent try, but they are not making it easy.


Yup thats Ali express for you....frustrating and deceiving.  You see an item listed for a low price so you click on it and the low price is actually just for one small component of the item.  So then you try to select the actual item you want from a small thumbnail and you wonder if you've actually selected it or not . The piss-poor description is not helpful at all.  Then you wait 3 to for months to see if you've got ripped off or not.   It better be pretty damn cheap for the hassle.  

And believe it or not after my ranting, I have had some purchases from Aliexpress that I thought were worthwhile.  (Carbide end mills were some of the positive ones).


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## YYCHM (Aug 16, 2021)

The one good thing I have to say about AliExpress is that they promptly refunded me in full after that VFD disaster.  It was however a good 5 month ordeal but most of that was the vendor's fault.


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## Tom Kitta (Aug 16, 2021)

Susquatch said:


> I opened an AliExpress account and tried to purchase some Azzkor bits from your link. I'll be honest, I can't figure out what I'm getting, what size, or even how many. Scrolling right and left on the product images doesn't help clear things up. Maybe I am trying to hard,.... Or maybe not hard enough. Right now I'm frustrated. I plan to try again in the morning.
> 
> I also looked for some HSS bits and failed at that too.  I'd like to give AliExpress a decent try, but they are not making it easy.




got to https://www.aliexpress.com/item/32896890158.html?spm=a2g0s.9042311.0.0.5b284c4dr37Xu3 

select 12mm x 75

select how many you want - default 1

click "buy now" - it will now ask you to sign in if not signed in.

review your order, click "place your order".

It is about as easy as Amazon.ca

Current price is just 11.32 CAD (!!)

Once you click "place your order" after about 2 seconds it will say "payment successful". 

I just ordered 1 to test it out - arriving on Sep 10th or before.


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## PeterT (Aug 16, 2021)

Finding parts on Ali is sometimes like that Wheres Waldo. After a while your eyes cross & you feel motion sickness. Then you scroll down to see a matrix of many size offerings, only to discover none of the part numbers line up, or they have different ones, or only a subset of the ones.... Some sites are better than others but can drive you batty. Inserts commonly use different (ISO) notation to NAm. I try & stick with machine/cnc related sites, avoid sites selling endmills, lipstick & crazy glue.

I checked my favorites store (you can save them). I've used BB, Ucheer, Dreanique, Leader. Of course depends on what you are after. Toms site ^^ loosk pretty good. Pay attention to EM cutting length, total length, corner rad & type of course.  I really don't find the coating makes a difference if they are good quality but I prefer uncoated carbide for aluminum which I reserve for aluminum.


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## Tom Kitta (Aug 16, 2021)

They have uncoated for AL as well - I think even touch cheaper.


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## Susquatch (Aug 17, 2021)

YYCHM said:


> It's not you.  AliExpress is strange and a bit deceiving actually.  I had a hard time getting my head around the presentation initially.  When I ordered my first DRO I really wasn't sure what I had purchased until it arrived.
> 
> Can you provide a link to the page you're looking at.



The link @Tom Kitta provided a few posts ago.


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## Susquatch (Aug 17, 2021)

O





Tom Kitta said:


> got to https://www.aliexpress.com/item/32896890158.html?spm=a2g0s.9042311.0.0.5b284c4dr37Xu3
> 
> select 12mm x 75
> 
> ...



OK, I succeeded. But not without a lotta pain. 

Hurdle 1 - I eventually figured out that the photo isn't what you are getting. You have to select size and then quantity separately. Then pray what you selected is similar to at least one of the bazzilion pictures displayed. Hurdle 1 cleared. (I Hope.....) TBD around Sept 11th.

Hurdle 2 - Next came entering a shipping address. Got it all in except postal code. It wouldn't let me enter a postal code! After much Fg around, I tried creating one in a text message and then copied that to my clipboard and then pasted that into the postal code and then finally saved my default address. Hurdle 2 cleared. 

Hurdle 3 - Next came payment details. PayPal isn't one of the options. Hmmmm, I really don't like the idea of sharing credit card info overseas.......... But Google Pay to the rescue.  They allowed me to create a one-time use credit card that AliExpress accepted. (I love that about Google pay!) Hurdle 3 cleared. 

Hurdle 4 - they won't let me NOT SAVE my credit card info. WTC! (where C = F) It gave me the option to not save but then gave me all these reasons why saving is a good idea. From this screen you go into a do-loop unless you choose save. Oh well, I guess I'll have to "update my card" every transaction......  Hurdle 4 cleared. 

Order placed successfully.

I don't know why PayPal isn't an option. I find that a bit scary. I'm guessing that PayPal had trouble with them and took them off their vendor list. If so, I don't know why I should trust them anymore than PayPal doesn't!

But I do love Google Pay. I use it for almost all my debit/CC payments now. It is SOOOO FAST, that it's scary. Get your phone within 6" of an RFC payment terminal and you are done. Simple as that. But best of all, every transaction is ghosted. The vendor gets a one-time use card, they never see yours. And you get an electronic receipt instantly.

Anyway, it's done. Now we wait and see.


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## Susquatch (Aug 17, 2021)

Tom Kitta said:


> They have uncoated for AL as well - I think even touch cheaper.



So how do you search for that?


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## Susquatch (Aug 17, 2021)

PeterT said:


> Finding parts on Ali is sometimes like that Wheres Waldo. After a while your eyes cross & you feel motion sickness. Then you scroll down to see a matrix of many size offerings, only to discover none of the part numbers line up, or they have different ones, or only a subset of the ones.... Some sites are better than others but can drive you batty. Inserts commonly use different (ISO) notation to NAm. I try & stick with machine/cnc related sites, avoid sites selling endmills, lipstick & crazy glue.
> 
> I checked my favorites store (you can save them). I've used BB, Ucheer, Dreanique, Leader. Of course depends on what you are after. Toms site ^^ loosk pretty good. Pay attention to EM cutting length, total length, corner rad & type of course.  I really don't find the coating makes a difference if they are good quality but I prefer uncoated carbide for aluminum which I reserve for aluminum.



They have stores? I thought AliExpress was a store...... So it's a bit more like e-bay then???


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## PeterT (Aug 17, 2021)

I don't know really. Whenever you land on an item, you can drill outward & inevitably see other items as part of a 'store' with a unique name. Sometimes it represents other similar items (machining for example). Sometimes it resembles someones closet... which it may well be. AliExpress is the overall umbrella selling website. In Ebay you can see individual people items but also stores.

In terms of payment you are pretty much confined to the modes they specify. Payment & credit cards are big business, tiny fees times bazillions of transactions. I think I had to set up AliPay which boils down to providing CC#. Truth be told I have had no issues & when an item didn't land in time or wrong item, it was dealt with expediently. But like most e-things these days, this is a personal decision if you want to play the game or not. Some people prefer (or also use Bangood). I have also see the exact same seller on ebay as Ali so its an inter-twined world.


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## charlton (Aug 17, 2021)

Susquatch said:


> They have stores? I thought AliExpress was a store...... So it's a bit more like e-bay then???



AliExpress is *very* much more like ebay. Most sellers have a "Visit Store" button that will take you to their page where you can search and filter for items that they offer.


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## Susquatch (Aug 17, 2021)

YYCHM said:


> It's not you.  AliExpress is strange and a bit deceiving actually.  I had a hard time getting my head around the presentation initially.  When I ordered my first DRO I really wasn't sure what I had purchased until it arrived.
> 
> Can you provide a link to the page you're looking at.



You bought a DRO on AliExpress? Wow, that must have taken some trust....... 

A DRO for my lathe has been on my wanted list for years. I'm gunna look and see if there are any good threads on getting a decent DRO on the forum. If not I'll start one. It's about time!


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## Susquatch (Aug 17, 2021)

PeterT said:


> I don't know really. Whenever you land on an item, you can drill outward & inevitably see other items as part of a 'store' with a unique name. Sometimes it represents other similar items (machining for example). Sometimes it resembles someones closet... which it may well be. AliExpress is the overall umbrella selling website. In Ebay you can see individual people items but also stores.
> 
> In terms of payment you are pretty much confined to the modes they specify. Payment & credit cards are big business, tiny fees times bazillions of transactions. I think I had to set up AliPay which boils down to providing CC#. Truth be told I have had no issues & when an item didn't land in time or wrong item, it was dealt with expediently. But like most e-things these days, this is a personal decision if you want to play the game or not. Some people prefer (or also use Bangood). I have also see the exact same seller on ebay as Ali so its an inter-twined world.



I see. In that case, I bet you can find those same sellers on Amazon too!

In this day and age of identity theft, credit card fraud, piracy, ransom ware, and infections of every kind imaginable and some unimaginable, I'd rather play things  on the safe side. I was using a credit card on line long before most people started doing it. So for me, it's not about learning to trust these outfits - it's about learning NOT to trust them. I do like what Google Pay has done to improve security. And PayPal is pretty good too.


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## YYCHM (Aug 17, 2021)

Susquatch said:


> You bought a DRO on AliExpress? Wow, that must have taken some trust.......
> 
> A DRO for my lathe has been on my wanted list for years. I'm gunna look and see if there are any good threads on getting a decent DRO on the forum. If not I'll start one. It's about time!



Actually I have purchased two DROs from AliExpress, both in the $300 range with scales.  Both went off without a hitch and fairly fast delivery.


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## Susquatch (Aug 17, 2021)

YYCHM said:


> Actually I have purchased two DROs from AliExpress, both in the $300 range with scales.



OK, $600 off to AliExpress. You have my full attention.......

Please tell me more! Brand, model,  pros, cons, problems encountered, etc.


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## Tom Kitta (Aug 17, 2021)

Susquatch said:


> They have stores? I thought AliExpress was a store...... So it's a bit more like e-bay then???



Its like Amazon. 50% of stuff is sold by amazon. Less profitable stuff is sold by sellers that can have lots of listings.

On ali its more organized - each seller has a store - where he sells items. There is no AFAIK aliexpress only selling - just third party.

Think of it as a large building called a bazzar. In this bazzar you have stalls - each stall is a store. Each stall rents itself from the bazzar owner. Its same system like a 1000 years ago (or even 2000) but electronic. If someone cheats you you can complain to bazzar owner whom will come down on stall owner for being a cheat.

Aliexpress is generally good to deal with - slightly better then say eBay and a bit worse then Amazon. Far better to deal with then most Canadian businesses. 

Generally big ticket items - like DRO do not need a lot of trust - items over $100 usually have plenty of tracking etc. I got multiple DROs and my parents even got a very large tent from aliexpress for like $300 (it is great BTW - way, way (100x way) better then crappy tire - even better then MEC). 

I know it can be a shock but the Asian market is way, way bigger then US. We do not see this due to our US centric view. We do not see the fact that China makes 2.5x more cars then US + Canada combined and growing.


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## Tom Kitta (Aug 17, 2021)

I got both of my DROs from aliexpress. I also got most of my CNC stuff from China (some from stepper direct, some from ali) - with other purchases in the last 6 months I easily spent there more then 2000. Heck I outspend amazon at least 10x with aliexpress. In fact aliexpress is my main go to place for everything other then heavy stuff. It is my main online shopping place for new items. 

No issues with both DROs. I tested them with uber precise indicator and they work better then on specs. There is zero reason I can think of of people buying expensive DROs. I would take brand new Chinese DRO over 20 year old Mitutoyo.


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## YYCHM (Aug 17, 2021)

Susquatch said:


> OK, $600 off to AliExpress. You have my full attention.......
> 
> Please tell me more! Brand, model,  pros, cons, problems encountered, etc.



This seller https://www.aliexpress.com/item/32847968410.html?spm=a2g0s.9042311.0.0.1cec4c4d63UFCs but what's pictured here isn't the same unit I purchased, it wasn't the LCD unit, it was a VM600-3. $209US shipped






And this seller

https://www.aliexpress.com/item/4001238045156.html?pdp_ext_f={"sku_id":"10000015417644927","ship_from":"RU"}&gps-id=pcStoreLeaderboard&scm=1007.22922.122102.0&scm_id=1007.22922.122102.0&scm-url=1007.22922.122102.0&pvid=70ad331a-8bba-431e-9ab6-705d1f77c35e&spm=a2g0o.store_pc_home.smartLeaderboard_725393586.4001238045156 $219US shipped






Both went off without a hitch and fairly fast delivery.


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## charlton (Aug 17, 2021)

YYCHM said:


> Actually I have purchased two DROs from AliExpress, both in the $300 range with scales.  Both went off without a hitch and fairly fast delivery.


I got my DRO off aliexpress as well. Also...without a hitch.


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## Proxule (Aug 17, 2021)

Tom Kitta said:


> Its like Amazon. 50% of stuff is sold by amazon. Less profitable stuff is sold by sellers that can have lots of listings.
> 
> On ali its more organized - each seller has a store - where he sells items. There is no AFAIK aliexpress only selling - just third party.
> 
> ...


Spent several K over the years!
Always have issues - from small to big. But never had an issue with full refunds.
I am and have been a platinum member on ali... they issue rerunds instantly when youre a gold and platinum member. Among other perks.

I wouldnt hesitate to spend 1k in a single transaction on ali.

Chooce aliexpress standard shipping and confirm HK post or ubi express as those reach me in alberta in less then a week.

After that you end up paying heavy $ for shipments with EMT DHL FEDEX or UPS

YMMV
gluck


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## Susquatch (Aug 17, 2021)

Tom Kitta said:


> Its like Amazon. 50% of stuff is sold by amazon. Less profitable stuff is sold by sellers that can have lots of listings.
> 
> On ali its more organized - each seller has a store - where he sells items. There is no AFAIK aliexpress only selling - just third party.
> 
> ...



Thats a great explanation @Tom Kitta. It makes sense to me. It also explains the mish mash of content  on the AliExpress Website. 

I did a 3 week consulting gig in mainland China 5 years ago. There are many people who know way more than I do, but having been there on business (not as a tourist) I can tell you many many amazing stories that no one would ever believe unless they experienced it first hand.


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## Susquatch (Aug 17, 2021)

Proxule said:


> Spent several K over the years!
> Always have issues - from small to big. But never had an issue with full refunds.
> I am and have been a platinum member on ali... they issue rerunds instantly when youre a gold and platinum member. Among other perks.
> 
> ...



This is great info. Thanks for the endorsement. How does one become a platinum or gold member. Sounds like it would be worth it.


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## YYCHM (Aug 17, 2021)

Susquatch said:


> I did a 3 week consulting gig in mainland China 5 years ago.



What kind of consulting?


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## Proxule (Aug 17, 2021)

Susquatch said:


> This is great info. Thanks for the endorsement. How does one become a platinum or gold member. Sounds like it would be worth it.


Easy. Spend lots of money lol.
You get points for every successful transaction.


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## Susquatch (Aug 17, 2021)

YYCHM said:


> What kind of consulting?



Automotive Technology.


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## Susquatch (Aug 17, 2021)

Proxule said:


> Easy. Spend lots of money lol.
> You get points for every successful transaction.



I see. It's not likely I'll spend all that much. Maybe a DRO or two like @YYCHM though......


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## Tom Kitta (Aug 17, 2021)

Just checked and I am almost a Dimond member on aliexpress. I did not know such thing even existed.


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## Susquatch (Aug 18, 2021)

Tom Kitta said:


> Just checked and I am almost a Dimond member on aliexpress. I did not know such thing even existed.



Lucky you. But if I understand the system, there was no luck involved. You earned it the hard way - with an "Express" Drain connected directly from "Ali" to your wallet.

So how do you know what your status is?


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## Tom Kitta (Aug 18, 2021)

Susquatch said:


> Lucky you. But if I understand the system, there was no luck involved. You earned it the hard way - with an "Express" Drain connected directly from "Ali" to your wallet.
> 
> So how do you know what your status is?



You go to your account and it tells you - I never actually looked at the "account" link before.


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## kevin.decelles (Aug 18, 2021)

I'm diamond as well.  Not sure what that means.  I have no issues with the service, and have had more issues on ebay in past 3 years than Alli.


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## YYCHM (Aug 18, 2021)

It would appear that I'm a gold member.....


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## Susquatch (Aug 18, 2021)

Go figure. I have zero points even though I did order some bits already.

The points rules are odd. They are calculated monthly on a rolling basis. So that big buy you made last September that got you platinum status is gone in October and then you are a just a silver schlump like me......

But you get points by reviewing, commenting, and even just for shopping at those milling and lipstick joints......

For anyone interested, here are their rules.


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## Susquatch (Aug 18, 2021)

I spent much of today trying to figure out how I managed to break that mill bit. (and finishing up some parts 

I noticed something interesting but I can't explain it. 

Note that all discussion below is about the part moving, not the bit - that is after all what actually happens.

I was milling conventionally with the part moving from right to left behind the bit. The bit was a 2 flute 1/2" HSS End Mill. I was cutting about 1/4" at a crack - roughly half of the end mill diameter. The depth was about 20 thou per layer. But changing the depth more or less didn't have any affect on what happened. 

Before I started the cut, I took the backlash out of the y axis by pulling the part toward me till it moved an 8th of an inch or so, and then pushing the part away from me till it reached the desired width of cut - about 1/2 of the end mill diameter. To my way of thinking, the bit wants to pull the part toward me so the part must be pushed back toward the rear after using up all the backlash in that direction. At least that's how I thought it was supposed to be done. 

However, almost as soon as the cut starts, the part starts to drift toward me even though the y-axis handle has not moved at all. What? And Why? 

If I take the y axis backlash out in the opposite direction by pulling the part toward me instead, THE EXACT SAME THING HAPPENS and the part starts to drift toward me.

In my newbie opinion, the latter case is perfectly normal. In fact, it is what I would expect to happen. The cutter is simply pulling the part toward me and is taking up the backlash I provided for it in the process. But the former example totally boggles my mind. There shouldn't be any backlash left to take up! I simply can't understand how that can happen. 

Note: It does not matter if the y axis is locked or not. The drift seems to be inevitable.

To get around the problem, I was able to guestimate how much the drift is and compensate for it with a series of 5 thou cuts. The very shallow cut did not cause any appreciable drift regardless of how I dialed out the y-axis.

Recall, this is the mill with a tenth of an inch backlash - approx 90 to 110 thou depending on where you measure it.

Could it be that its not possible to take up that much backlash? Or could it be that the lead screw nut is moving vertically and allowing even more backlash, or perhaps it is on the verge of stripping? 

Or could it be that this newbie has a loose screw in his thinking?


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## Tom Kitta (Aug 18, 2021)

Yes it can happen - I have had my 12mm taking a heavy cut start "drifting" I could see it on the DRO. Heavy cut is full 12mm and say 5mm deep. Especially with dull EM. At this point one has to lock the axis as when milling X you can see Y drift if Y is not well locked. In fact X should be snug too.
Also make sure quill is locked and EM is very well torqued in the collet - heck you may now realize the "holder" existance. Also lock the knee if applicable. 

In the above example if the "locking" does not help something else is loose. 

I never had the backlash issue - when drifting it simply pulled the screw and handles started to move - it could drift an inch or more.

Examine all moving things - what else could be moving on your machine?

Taking a 20 thou pass with half of 1/2 EM is very tiny except maybe for the very smallest machines. 

I never take any "backlash out" on the axis I am not cutting on  - if it was left totally loose on Y and you were cutting left to right on the X axis (or right to left) the table would dance on Y - i.e. it would shake towards and away from you for the amount of the backlash - to prevent this you need things locked.


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## YYCHM (Aug 18, 2021)

2 flute 1/2" HSS End Mill???  I thought you cooked a 1/2" carbide endmill?


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## Susquatch (Aug 18, 2021)

YYCHM said:


> 2 flute 1/2" HSS End Mill???  I thought you cooked a 1/2" carbide endmill?



Yup, I did. But I bought one carbide and a few hss bits to replace it from KBC - free next day delivery....... A bit more $ than Ali Express, but faster than smell.


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## Susquatch (Aug 18, 2021)

Tom Kitta said:


> Yes it can happen - I have had my 12mm taking a heavy cut start "drifting" I could see it on the DRO. Heavy cut is full 12mm and say 5mm deep. Especially with dull EM. At this point one has to lock the axis as when milling X you can see Y drift if Y is not well locked. In fact X should be snug too.
> Also make sure quill is locked and EM is very well torqued in the collet - heck you may now realize the "holder" existance. Also lock the knee if applicable.
> 
> In the above example if the "locking" does not help something else is loose.
> ...



I'll reply in parts.

Locking the y direction does not make any difference.

I've never tried locking the direction I'm going in. Wouldn't that accelerate the leade screw wear?

No tool drift in the collet. No z drift either.

Something is moving. Yup! But what?


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## YYCHM (Aug 18, 2021)

Gibs loose?  Not adjusted properly?


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## PeterT (Aug 18, 2021)

Its kind of like driving a car where your steering wheel has a full turn of free play until it engages the steering mechanism on either end. Yes, driving is possible but generally not a great way to operate with any accuracy. Mill table locks (and their lathe equivalent dovetail slide locks) have a secondary purpose IMO. They also prevent wear & tear on the leadscrew/nut which will see these cutting forces. The table is heavy but its on a film of oil. With leadscrew removed its not difficult to slide table back & forth by hand. The cutting forces have to be resolved somewhere & that somewhere is a tiny area called thread leadscrew contact. So its good practice to lock the 2 non-moving axis. I often don't worry about the knee as much.


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## Susquatch (Aug 18, 2021)

YYCHM said:


> Gibs loose?  Not adjusted properly?



Excellent thought! That's a very real possibility. I have not looked at them or adjusted them yet. I'm still in the mill evaluation phase before deciding which one to keep. I'll try and do that tomorrow.


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## Susquatch (Aug 18, 2021)

PeterT said:


> Its kind of like driving a car where your steering wheel has a full turn of free play until it engages the steering mechanism on either end. Yes, driving is possible but generally not a great way to operate with any accuracy. Mill table locks (and their lathe equivalent dovetail slide locks) have a secondary purpose IMO. They also prevent wear & tear on the leadscrew/nut which will see these cutting forces. The table is heavy but its on a film of oil. With leadscrew removed its not difficult to slide table back & forth by hand. The cutting forces have to be resolved somewhere & that somewhere is a tiny area called thread leadscrew contact. So its good practice to lock the 2 non-moving axis. I often don't worry about the knee as much.



Now that there was a funny analogy! I've never seen a vehicle steering system with a full 360° turn of backlash. But they all have some. Most of it is taken care of by the alignment (toe-in, caster, and camber) adjustments which make the vehicle "want" to keep going straight and also take road crown into account. Sorry, I digress.....

I see your point about table locks saving wear and tear on the lead screw & nut. But as I said, locking the Y axis didn't change anything. But @YYCHM may be on to something......


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## PeterT (Aug 18, 2021)

Oh I thought your gibs were adjusted. Ya that's worth checking too. But unless its horribly loose to the extend of rocking laterally, gib/dovetail fit is more about the table resistance feel. Your 0.1" float is an issue.


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## RobinHood (Aug 18, 2021)

It’s probably the gib on the axis you are moving on, as Craig is suggesting. Why? The lock engages the gib and pushes it into the dovetail. So even if the gib were loose, the lock would make the locked axis tight. But since, in your example, you are moving in X with a possible badly adjusted gib, the table can “float” in the dovetails, causing what you are seeing. What Tom was saying is to apply the moving axis’s lock a tiny bit to take up the last bit of play in the dovetail - kind of like driving with a dragging brake. It helps until you have time to investigate and adjust as necessary.

Fasted way to test is to put a DI mounted to the mill base that is indicating on the rear of the table. Lock the knee, and Y. Pull in the Y +/- direction on a table end. Observe the DI. It should not move substantially with a properly adjusted X gib. You can run the same test with X locked off and Y unlocked. Again DI should not move if Y gib is adjusted properly.


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## YYCHM (Aug 19, 2021)

Susquatch said:


> Yup, I did. But I bought one carbide and a few hss bits to replace it from KBC - free next day delivery....... A bit more $ than Ali Express, but faster than smell.



How did you manage to get free next day delivery from KBC?


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## Dabbler (Aug 19, 2021)

Susquatch said:


> BUT, parting off is my nemesis. I absolutely HATE parting off



I was there for nearly 20 years.  I finally tamed the beast... There are a bunch of things that work for better parting, and I'd be hesitant to try to 'remote control' any solution path.  'Winky' in the video below had a wonderful set of ideas to get the thinking juices rolling:


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## Susquatch (Aug 19, 2021)

That is REALLY COOL. Now that I have a mill, I'll be making myself one of those! It won't be exactly the same because my aloris holder is different. But I totally get the principal of the thing. And I agree with him too. Rigidity, rigidity, rigidity. Those are the three main secrets to successful parting off. But it's not always possible for me. I especially hate those parting tool holder adapters that get held like a 1/2" tool bit. They never work on anything but aluminium. 

I've tried every trick in the book or at least looked at them with a very earnest sincere eye. I can part off aluminum or brass with zero problems. Regular steel works great too as long as the depth is less than about 1/4 inch. For parts or stock bigger than 1/2" OD,  things go to hell in a handbaslet. I believe your friend is right though, and that may very well work for me too. I'll need to get or borrow a bandsaw though. Or maybe design something that doesn't need one. 

There is one trick that works every single time, but I don't like to use it unless I have to. That is to turn the parting tool upside down and run the lathe in reverse. I feel like that is not good for my saddle, but there is no doubt that it works.

The other thing that also works sometimes is to make side by side cuts. I can often get down a half inch that way. But it's really slow going and the bit inevitably starts to bend and the cuts join. That's about when I give up and get the hacksaw or flip the tool.


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## Susquatch (Aug 19, 2021)

YYCHM said:


> How did you manage to get free next day delivery from KBC?



I was hoping someone would ask that question! Thanks for not disappointing me! It's really very simple. 

Their shop in OldCastle (where they first started their business) is just 40 minutes away. My son drives right past there everyday on his way to work and then again on his way home. He picks stuff up for me and then swings by here on the other leg....... 8)

Same day delivery is also possible if they have stock and I'm desperate.


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## kevin.decelles (Aug 19, 2021)

I do parting occasionally and based on my first experiences, I have one foot on the brake and wear a full face shield.   Over the past year I've only had success, and I attribute it to alignment and speed.  I recently parted some 4340 using a carbide insert.  It HOWLED like crazy until I turned it on the slowest possible speed (~80 rpm).  Once I got the right speed, it quieted down and cut decently.   sometimes 'more' speed is better.  I've learned to try different speeds in progression up/down until I hit the sweet spot.


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## Susquatch (Aug 19, 2021)

YYCHM said:


> Gibs loose?  Not adjusted properly?



The power went out today so I haven't been able to do much of anything until it came back on a bit ago. 

I think you nailed it. Using @RobinHood's suggested method it looks like I have around 45 thou sideways float on the X axis and more if I put some muscle into it. I can easy see how that would explain my shattered endmill and my later observations. I'll have to get in there and fix that asap!

Thank you!


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## Susquatch (Aug 19, 2021)

Dabbler said:


> I was there for nearly 20 years.  I finally tamed the beast... There are a bunch of things that work for better parting, and I'd be hesitant to try to 'remote control' any solution path.  'Winky' in the video below had a wonderful set of ideas to get the thinking juices rolling:



I practically dove at my lathe first chance I got today. The distance from the top of the compound slide to the spindle center line is only one and a quarter (1.25) inches. So it ought to be easy to make something similar to the one in your video. 

I had hoped to be able to use the T-slot Aloris Tool post that I bought ages ago for my old belt drive lathe and then abandoned the idea. The Aloris would make perfect parts for the job, but it looks like too much work and too much butchery. It will gather dust for another day and another job. 

Unless I come up with a better idea, I might have to buy a couple of blocks of steel for the job and make something custom.

Seems to me that a left over chunk of that 1/2" plate from the Hartford Motor Adapter plate could be machined to make a bottom plate, a block of 1.5x3x3 steel could be machined to make the top block with a separate piece to hold the cutoff blade at various heights for different blades, and two 1/2" Bolts to hold the base and block together on the compound would not be too difficult and would be more rigid than my lathe can ssupport. If that doesn't work, I'll just have to invest in a 115 KVolt Lathe mounted plasma cutter....... 8). 
Given how much parting off I do, it might even become a priority!

Thanks again @Dabbler!


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## Susquatch (Aug 21, 2021)

I spent as much time as is reasonable reducing the backlash and gibs on my Bridgeport. For details, see the thread: https://canadianhobbymetalworkers.com/threads/new-to-me-bridgeport-mill.3491/ 

In summary, I got the backlash down on both axis to 75 thou at the ends and 85 in the middle and then I believe the adjustment screws bottomed out. 

I also tightened the X Y and Z Gibbs as much as possible and again ran out of adjustment. 

I also discovered that the y axis lock was out of sync with the table  and although it felt like it was working, in reality it wasn't locking anything. It now locks the Y Axis solid as a rock. That probably explains the y axis drift even with the y-axis lock on. 

Even though I don't like the answer, I can at least take comfort in the fact that there is a satisfactory explanation for the broken end mill.

Thanks to everyone for helping me understand what happened and for all the other cool lessons along the way.


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## Susquatch (Sep 2, 2021)

Tom Kitta said:


> The company I use for past two years or so is Azzkor For example https://www.aliexpress.com/item/32896890158.html?spm=a2g0s.9042311.0.0.5b284c4dr37Xu3
> 
> Remember you can do imperial stuff with metric EM and metric stuff with imperial EM - its just touch more work. 12mm is touch smaller then 1/2 but you can treat it as "re sharpened" 1/2".
> 
> Prices are so good on this carbide it is hard not to go with it.



The Azzkor carbide end mills I ordered on Aug 17th, on Ali on came yesterday Sept 1st.  Two weeks. Not really that bad. 

VERY CONFUSING order process, but I did get timely order processing, shipping, and tracking notifications. 

The 4 carbide bits also SEEM to be very good quality on visual inspection. 

Now that they have my coordinates, they are practically drowning me in offers of various types. I've always wanted to try a threading insert and a parting insert, but never had the courage to order something I might only use once and then never touch again because it's horrible compared to HSS. I have a blade and insert bits in my shopping cart with Accusize right now that I was going to get to go with a custom tool holder I am planning to make with @Dabbler's input. Perhaps I'll try to get them from Ali instead. 

Also, at Ali's prices, I can see some R8 tooling in my future to replace a lot of my MT3 stuff. 

I also admit that I find it quite ironic that customs takes over a week to process stuff coming from the USA, while stuff from China gets processed in less than a day....... Pisses me off in a way....


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