Been looking at this mill...

[Chris Roy]

Been looking at this mill. Wondering people's opinions on it as a first mill with limited space and cost. Just looking for something i can slowly upgrade if I want but not be half my shop and weigh more than my truck Seems like this is similar to craftex CX601 from busy bee but 1000$ cheaper....Any info is appreciated, thanks.

https://www.kmstools.com/king-canada-milling-drilling-machine-with-digital-readout-11623

 

[PeterT]

I've seen some folks do decent model engineering work on the look-alikes to that model (possibly including Busy Bee). A lot equivalent discussion came up when someone was looking at King lathe. Its really hard to tell these days because some machines are just different paint & stickers. Others 'look' the same 5 feet away & spec sheet wise, but are substantially different where it counts. If its Taiwan made, that would make me feel better inside. If its Chinese made, still not necessarily bad, but do some specific Googling of that name/PN with user experience. Of course you will always run into the odd horror story, it happens across all brands. But that's where you need to convince yourself the company will replace/warranty. It would be nice if they could give you a couple recent customer contacts to check with, but I suspect with all the information security that's not an option anymore.

A little bit more info here. maybe you can download the manual too, often they are PDF
http://www.kingcanada.com/Products.htm?CD=36&ID=21355

Its not a super heavy duty machine, so maybe first question is what kind of work are you intending? For the most part, if its accurate & repeatable, that's way higher on my list. I suspect it has dovetail on the z-axis column which is a lot less headache preserving center than round column mill/drills. Take a look at dials, sometimes they are fromage. Goofy things like metric leadscrew pitch so some bizarre scale like 1 turn = 0.150" vs an even 0.100". Generally the X&Y accuracy is pretty good, at least my King RF-45 is, But the Z is out to lunch & that was a pre-known. Personally I would budget for a Chinese DRO one day & be done with it. You will enjoy machining so much more & who cares what the dials say or backlash etc. R8 is a very common (N_Am) spindle so lots of tooling availability. I don't know much about the motor drive & electrics. Something to check into.

Hey does KMS run those machines for you if you want to hear it?

 

[PeterT]

I just did a quick Google. This link talks about some of the other 'equivalent' brands so you can maybe widen your scope & get a broader perspective. Its kind of looking like a one-factory / many-retailer model. Not that that's a bad thing at all. But just check into any re-occurring themes & then zero in on the King specifically.
http://bbs.homeshopmachinist.net/threads/45382-Anyone-know-this-small-mill

Another tip (personal regret actually). The sheet metal bases they sometimes package with these are a bit of hit & miss depending on the model & the day they were made. At best they are 'ok' but at worst can actually create secondary issues if machine is not mounted properly; resonance, vibration etc. Id rather pay a buddy welder & get a frame built made of say 2" square tube. It will be much more solid & you can incorporate other desirable features - wheels, shelves, proper leveling feet etc.

 

[John Conroy]

That King machine is closer in size to the Busy Bee CX 600. It is much lighter than the CX 601

 

[PeterT]

Yeah, you're right. Looks somewhere in the middle depending on specs. It doesn't seem to be a re-paint of a BB.
HP: CX600 = .75, CX601=1.5, King = 1.0
Xtravel: CX600 = 15", CX601=16.7" King = 18.8"
Ystroke: CX600 = 2", CX601=2.7" King = 2"
etc. etc.

Another spec I'd check is headroom (distance under quill to table top). That gets gobbled up in a hurry with vise or rotary table on bottom & chuck/mill cutter on top side.

 

[Alexander]

These machines are way better than a round column Mill drill but they do have some distinct disadvantages over a knee mill. The big one is I cant quite figure out how to plunge with an endmill to cut a keyway or a slot. You could feed in with the quill handle but thats not very rigid. And if you unlock the head and try to feed it in with the hand wheel you will be fighting the backlash in z if the cutting forces equil the weight of the head. It was enough to scare me away. Decent knee mills go for $1500 on kijiji every now and then. I didn't pay more than that for mine and it weighs over 2500lbs

 

[PeterT]

Super good point Alex. I haven't looked at these particular machines up close... just assumed that's what the front knob was for. (So what IS the front knob for?). Conventional mill typically has some form of gear reduction on the quill to gradually increment depth. (You can also go drill press mode by releasing a tension knob, but for milling, yes fine feed is necessary).

 

[John Conroy]

You're right Alex. When I still had my PM932 I did mill a couple of key slots by moving the quill down with the fine feed that Peter pointed out. However the backlash in the quill down feed rack makes it possible for the cutting forces to suck the end mill down into the work making it hard to control the depth and possibly breaking the end mill. That's one of the reasons I wanted a knee mill.

 

[Chris Roy]

Thanks for the input guys. A lot to digest lol I think i'll just keep looking around. Been looking at the grizzly website as well and the G0704 seems to be about the same price with freight and exchange. A unit roughly this size would be ideal considering I could move it around the shop if needed but from what i've been reading lots of people saying to stay clear of the Chinese mills but I just don't want anything too large. I'll keep researching i guess but I appreciate the input. Never milled before so I'm not looking for anything crazy to learn on I just don't really want to out grow the machine in a few months either.

 

[PeterT]

Hmm.. I learned something new here too. I haven't don't that much direct endmill in-plunging on my RF-45. Mostly the EM is off part & then traverse cutting, or partially off-part & plunging. When I did plunge with endmill. I always lock the head & put a bit of tension on the quill lock screw as I entered vs. leaving it full float. I always assumed any end mill grabbiness had more to do with the lip / cutting geometry or the material. I'll have to experiment on this. I've seen some CNC retrofits of RF-45 mills & from recollection they just drive the EM in there. Do you think that's because the Z backlash is now constrained by the different ball screw leads screws & that's tighter setup than the non-CNC perpendicular worm gear depth setup?

 

[Janger]

I have a BB CX601. It looks very very similar to that King referenced above. I don't buy it has a 1HP motor either, the current is rated at 4.8A so 4.8A * 115V = 550W and that is not a 1 HP motor. It's 0.75 HP. It is hard to tell by the pictures - the cx600 is a substantially beefier model. More money for sure and about 110 kg more mass too. If you go to the store and look at them the models are much easier to understand. Funny how they all look the same on the internet. The knob on the front is the fine feed when you lock the quill handle BTW. Every time I look at those machines they are a few hundred more! I got my CX601 for $1300ish and now they are $1825! It's only been about a year. The dollar....

Interesting I saw Keith Fenner in his Beaver Repair video (omg just go watch it) have his mill get away from him and suck the bit down into a keyway. Very experienced guy with good equipment - and he still got nailed by that problem.

 

[PeterT]

So this whole keyway grabby thing - are you guys saying problem is mostly averted by 'lifting' the table/work up into the endmill (kneemill) vs. feeding endmill down into work via the fine spindle feed ... or?
Isn't the bottom crank handle moving engagement distance via a screw in the same manner? Or maybe its because against the table weight its always zeroing out the backlash (and I assume head/quill is now locked). Hmm... I always assumed the lift handle was kind of a coarse 'get it roughly into position' thing & then you controlled depth on the topside the same manner for all mills. (Can you tell... I don't have a 'lifter' model

 

[PeterT]

Janger, interesting power observation. I wonder if they upped the motor, or maybe its one of those - how much power do you want & we will attach an appropriate sticker type deals

 

[Chris Roy]

the bb cx601 is 2499$ I believe. Think I'm just gonna kijiji scan for a bit and see what happens lol

I have a BB CX601. It looks very very similar to that King referenced above. I don't buy it has a 1HP motor either, the current is rated at 4.8A so 4.8A * 115V = 550W and that is not a 1 HP motor. It's 0.75 HP. It is hard to tell by the pictures - the cx600 is a substantially beefier model. More money for sure and about 110 kg more mass too. If you go to the store and look at them the models are much easier to understand. Funny how they all look the same on the internet. The knob on the front is the fine feed when you lock the quill handle BTW. Every time I look at those machines they are a few hundred more! I got my CX601 for $1300ish and now they are $1825! It's only been about a year. The dollar....

Interesting I saw Keith Fenner in his Beaver Repair video (omg just go watch it) have his mill get away from him and suck the bit down into a keyway. Very experienced guy with good equipment - and he still got nailed by that problem.

 

[John Conroy]

Chris, I think you're doing the right thing. You're bound to find a deal on kijiji if you are willing to wait for it. I waited for a year to find the knee mill I bought last winter.

Peter, you're right. When you lower the quill the backlash in the feed allows the quill to float up then be pulled down by the cutting force of the end mill. That can happen on any mill if you hand feed the quill. The distance it gets sucked down depends on how much backlash you have. The same thing is possible when you lift he table up into the work on a knee mill but the knee and table on a Bridgeport type mill weight about 600 lbs so that is unlikely to happen but if you're using a large end mill it can happen on a knee mill too. I've seen an end mill get sucked down out of a collet if the drawbar is not tight enough, there is a lot of force generated when deep cuts are taken.

One guy on another form went to great lengths to try to work around that issue with his PM 932, it is an interesting read.

http://www.hobby-machinist.com/threads/pm-932m-pdf-experience.22195/

When I cut a slot on my PM 932 and hand feeding the quill was needed because the slot was closed a both ends, I would use a smaller end mill than needed and hand feed down in small steps until the totals depth was achieved. Then feed the table laterally to widen the slot to the correct size with the quill locked. This method makes it possible to get very accurate dimensions with little risk as the small end mill does not create much downward pull.

Janger I watch all of Keith Fenner's videos too. He's a very skilled guy and it's great that he is taking the time to pass along his experience and knowledge to others with his videos. When he makes a mistake he doesn't edit it out, he explains what happened so his viewers can avoid the same error.

 

[PeterT]

Thanks John. Good link. Funny, I was just thinking along the same lines - 'anti-backlash spring'. He had a novel way of winding it up & hiding inside the box. My idea was a little <ahem> uglier. There aren't many easy solutions to this from what I can tell. You need some sort of worm gear to get the fine depth resolution & probably some mechanical advantage too. So any backlash - which any gear train is going to have to some degree - is going to see this issue to some extent. Hmm I'll have to pay more attention to this. But yes, I can now see in certain milling situations this is a heads up deal. I think maybe my 'partial friction' technique with the spindle lock nut wasn't solving the problem, but maybe dampening the kick? Mind you so far I haven't faced this plunging situation many times. But its inevitable.

I wonder if one could rig up a teeny 'gas spring'? Kind of like those weight lifting assist cylinders on my hatchback, but in reverse - giving some constant-ish force to the spindle? Probably hard to accommodate the z-travel range without a longish cylinder?

 

[PeterT]

like this principle
http://www.ameritoolmfg.com/ProductInformation/TensionGasSprings.aspx

Of course, with this in place, now drill press mode is gong to suck

 

[Chris Roy]

Saw this today. http://www.kijiji.ca/v-business-ind...ct/1143815414?enableSearchNavigationFlag=true
Anyone have any experience with this type of mill?

 

[PeterT]

It looks to be a generic varietal of my King RF-45 (RF = Rung Fu)... which also has cousins under different paint schemes. John is better to comment, but I believe a prior Precision Mathews model. And Grizzly, possibly? model # G0755? Sorry I don't recognize that particular ZAY7045L name & that's where things get 'interesting'. Guessing China but maybe Taiwan? Does it matter? There was a local company bringing in mills like that but I thought they were full CNC retrofits, not kits. I guess if it checked out & you flogged the CNC components parts (unless you were so inclined) might be worth a looksee. The question is always 'parts' if necessary. Its hard enough to chase down so called brand names (distributer names really).

 

[Chris Roy]

Thanks Pete. Tried looking up the mill and can't find much. Priced out his CNC components as well and it seems pretty pricey. He's already dropped it 600$ in the last 2 days