BaitMaster’s (Work) Bench

[gerritv]

I've had more trouble with 10x22 lathe parting off than I think I did with my Atlas 618. I think the culprit has been torque power. On my Atlas 618 it had a bull gear and it had reasonable torque. On my 10x22 it has variable speed DC motor and I can slow it down to 50 rpm which is nice but it doesn't have much torque at that speed and then it stall and all hell breaks loose.

with carbide I part off at 300+ rpm. Slower is not better. I have a 1022 with DC treadmill motor. The thing that does inserts in is grabbing and then the part reverses a tiny bit. Bingo goes the tip. A 1" diameter 12l14 or other CR (non-alloy) parts at +300 RPM. Push cutter in and keep feeding.

The 1022 carriage likes to raise up as well, have to lock it for results. All bets are off if you still have the compund installed.

 

[StevSmar]

Anyways, try HSS upside down. I bet you gunna LUV it!

Do you use a parting tool specifically for upside down?
Like this one:
Eccentric Engineering For16 Parting Tool

 

[Susquatch]

Nope. Just a regular blade flipped upside down. If it's mounted in one of those T holders that fit a regular tool holder you can flip that upside down instead. Just make sure the blade has side clearance and doesn't rub. Present the blade to the work the same as it would normally be with the cutting edge on center.

Imagine the worst case. A blade chattering or squealling or digging in or even bouncing. All gonesville.

 

[Tom O]

 

[PeterT]

I don't have problems parting with carbide on my Taiwan 14x40 & always do it in conventional direction. I use HSS T-blades as well & really can't see much of a difference. If you have a tough material, particularly like SS that may work harden or certain gummier alloys, that can present challenges regardless. I would wager that there is something fundamental in the lathe setup that is causing problems. We have discussed this many times before. Cutting surface has to be perfectly aligned + carriage locked + compound locked + smooth perpendicular infeed + no rocking or play or distortion on the tool holder, tool post, compound, cross slide, saddle.... Having said all this, I generally part only when I have to or its just easier/quicker. A saw is a much more efficient tool, less wear & tear on the lathe.

Have you guys put a DTI on the tool surface to get a handle on physical deflection while parting? Are you rear-parters removing the compound & replacing with a different (more rigid) tool holder or wider aspect ratio blade/holder? I've read of people temporarily putting a machinist jack type support under the parting blade/holder & low & behold, chatter disappeared & infeed improved. Its not a solution but its pointing to a rigidity / deflection problem, not a cutting tool problem.

ps - those Accusize prices seem pretty high for what I can only guess is the same hardware from China. Quality can vary by Ali sellers so I try to stick to machinery sellers, but so far have had good luck with them. I have seen some toolholders where the indexing tang was not correct for the inserts, which meant they were not seating properly. I do dabble with different inserts of the same family, but even the so called specialty ones are not expensive.

 

[Upnorth]

https://www.amazon.ca/gp/aw/d/B07BGJ7T6N?psc=1&ref=ppx_pop_mob_b_asin_title

View attachment 52257I did try the aggressive carbide approach. And all of the times I’ve tried it I’ve squared my toolpost, tightened gibs, made sure my tool was perfect center height using the tailstock with a center, etc.

I was working in a machine shop doing electrical and I asked the head machinist when I was done about my parting woes. He said to shoot for 400sfpm on my carbide parting tool and slam it in power feed on a lower feed rate if my lathe could.

I paced back and forth in my shop for about 15 minutes wondering if I was actually going to and I eventually worked up the gall to try it. It looked beautiful up until there was about 1/4” of material left at which point the carbide parting tool decided to LEAVE THE CHAT in violent manner.

I’m definately done with carbide parting on my utilathe. If I upgrade to a larger/more rigid machine one day I may try it again, but after trying the HSS and not having a single sketchy thing happen, and to be able to go nice and slow and controlled, it’s night and day.

I bought this exact tool to use on my Harrison 13" lathe. It was a 100% disaster. No matter what I tried to part it failed. Eventually the tool broke and it went into the garbage. I then bought a tool from KBC and now lathe parting is easy. Power feed or hand feed it just works. Inserts last quite a while in tool steel. I can post a photo of the tool I use now if you want to see it.

 

[BaitMaster]

I bought this exact tool to use on my Harrison 13" lathe. It was a 100% disaster. No matter what I tried to part it failed. Eventually the tool broke and it went into the garbage. I then bought a tool from KBC and now lathe parting is easy. Power feed or hand feed it just works. Inserts last quite a while in tool steel. I can post a photo of the tool I use now if you want to see it.

Post pic please! Good information to have.

 

[Susquatch]

I can post a photo of the tool I use now if you want to see it.

Yes please. And a link too - if you can.

As per comments above, I'd love to find something that can part 4 inch stock. So far, I'm stuck at 2 with my current Insert tool because 1" is all the tool can handle.

And yes, I know that both tool and part stick out are significant barriers to rigidity and smooth parting.

I can cut a 4" part with an upside down blade but I'd like to be able to cut normally too.

My current thinking is to make a plinth type single purpose parting tool holder that will accept an insert blade or a HSS blade.

 

[Upnorth]

I was unable to find the original tool in the KBC tool catalog. It's possible that I bought it from Travers tool Canada. I had no luck with the one in your photo. I had minimal success with the type that uses a HSS blade and clamps directly in the lathe tool holder. The one I use takes GTN style inserts. They last a long time if you buy good ones. I'll add in a third photo from the Travers tool catalog to show you the type.

When I first got my tool it said "Made in India" on it. Based on previous experience I was not expecting much. It has made parting go from impossible or at best intermittent to easy. I think now the one I might have bought was made by Terra Carbide. My advice is to buy something decent and don't go to cheap when it comes to parting. Despite it's flimsy appearance it cuts extremely well. I do set up my cutting block with a dial indicator to make sure it's perfectly parallel. I think this one might be the one that I have. Link to parting tool. You will have to pick the one that suits your machine.

TERRA CARBIDE 05-0325-06 - GTN 2 Cut-Off / Parting Set with Blade, Block and Inserts, 0.087

Terra Carbide Presents its Everest Series of GTN Block, Blade & Insert Sets. The GTN carbide inserts offered along are of grade EVC5T and insert width 0.087 inch or 0.122 inch. Whether you are parting off small components or grooving large diameters, you will find the right set for your...

www.traverscanada.com

TERRA CARBIDE 05-0325-06 - GTN 2

 

[Upnorth]

Yes please. And a link too - if you can.

As per comments above, I'd love to find something that can part 4 inch stock. So far, I'm stuck at 2 with my current Insert tool because 1" is all the tool can handle.

And yes, I know that both tool and part stick out are significant barriers to rigidity and smooth parting.

I can cut a 4" part with an upside down blade but I'd like to be able to cut normally too.

My current thinking is to make a plinth type single purpose parting tool holder that will accept an insert blade or a HSS blade.

Wow 4". I never part anything that big. Most difficult thing I have parted is 1" tool steel.

I forgot to mention in my previous answer to Baitmaster that sometimes you are doing nothing wrong when parting. I have tried to part tool steel that turned out to be 100% garbage. Switching to another piece of stock fixed the issue.

 

[DPittman]

Wow 4". I never part anything that big. Most difficult thing I have parted is 1" tool steel.

Yup I agree I think 4" is definitely band/dry cut saw material. On a small lathe anything over 2. 5" steel and I'm looking for a saw.

 

[PeterT]

Another trick to remember if you have done machining to a large diameter part & just want it lopped off (parted) but there isn't much remaining length to grip in the saw vise or similar work holding issues.
Just leave the part in the chuck, its already perfectly gripped. Remove the chuck from lathe, clamp it within the saw jaws & buzz the part off no problemo. I thought I had an action picture but it isn't hard to visualize. Some guys even use a plywood shop made vee-block type affair to grip the jaw with more contact area & wont risk marring your baby. I do recommend sealing off the open jaws because saw swarf & cutting fluid can get in the scroll works & make a mess. Aluminum foil does a great job & takes like 10 seconds.

 

[Susquatch]

Just leave the part in the chuck, its already perfectly gripped. Remove the chuck from lathe, clamp it within the saw jaws & buzz the part off no problemo.

Cool trick Peter! I like it.

Yup I agree I think 4" is definitely band/dry cut saw material. On a small lathe anything over 2. 5" steel and I'm looking for a saw.

To be honest, I think I have only parted 2.5" stock to date. I agree that a band saw is probably a better choice most of the time. But that doesn't stop me from wanting to part bigger!

For me, this is mostly about exploring the possibilities. If I can successfully part 2.5", then why not 3"? If I can part 3, then why not 4. That doesn't meant I'll ever actually need to. And if I did, I'd prolly use a band saw or even a hacksaw. I fact, I'm not ashamed to admit that I often used a hacksaw on a part turning on my lathe before I got the band saw.

 

[BaitMaster]

So the BaitMasters Belt Grinder Build has officially started. I’ll try to take some pictures to show.

I’m building 2 identical grinders, one to keep, and one for a horse trade with my Autobody/Mechanic guy for some much needed body work on my pickup.

I decided on using the Jer Schmidt plans, as they seemed the most robust and useful out of all the ones I looked at. They also were economical to build. The plans seem fantastic.

I have all the materials required already, the costs for the grinders both with all the material in the lists coming in right at 2300 CAD for me.

I’m not going to list the prices of some of the parts publicly as I get some considerable discount due to my employ….. but I will give you a more detailed list if you are considering building this grinder and you PM me.

I will say the metal, which a considerable portion I had laser cut for a very reasonable fee, was about 460$ per grinder. Wheels were about 180$ per grinder. Hardware was about 60$ total for both grinders, with the electrical portion I’m not going to detail taking up the balance.

I’m in the process of cutting up flat bar and doing some drilling and tapping right now, with pictures to come when I start welding.

Looks to be an awesome kit! I’m pretty stoked. Stay tuned.

Edit: The electrical I am using 3ph 2hp TEFC motors with VFD’s for both. I’m not doing the janky single phase single speed… before someone asks.

 

[Jswain]

So the BaitMasters Belt Grinder Build has officially started. I’ll try to take some pictures to show.

I’m building 2 identical grinders, one to keep, and one for a horse trade with my Autobody/Mechanic guy for some much needed body work on my pickup.

I decided on using the Jer Schmidt plans, as they seemed the most robust and useful out of all the ones I looked at. They also were economical to build. The plans seem fantastic.

I have all the materials required already, the costs for the grinders both with all the material in the lists coming in right at 2300 CAD for me.

I’m not going to list the prices of some of the parts publicly as I get some considerable discount due to my employ….. but I will give you a more detailed list if you are considering building this grinder and you PM me.

I will say the metal, which a considerable portion I had laser cut for a very reasonable fee, was about 460$ per grinder. Wheels were about 180$ per grinder. Hardware was about 60$ total for both grinders, with the electrical portion I’m not going to detail taking up the balance.

I’m in the process of cutting up flat bar and doing some drilling and tapping right now, with pictures to come when I start welding.

Looks to be an awesome kit! I’m pretty stoked. Stay tuned.

Edit: The electrical I am using 3ph 2hp TEFC motors with VFD’s for both. I’m not doing the janky single phase single speed… before someone asks.

Badass! Can't wait to see this

 

[BaitMaster]

Here’s some pics

 

[BaitMaster]

Of note is I made a couple substitutions on the parts list, to save money. The McMaster carr parts I swapped out for Amazon stuff. I had to adapt and switch some threads from 3/8” to m10 for the locking adjustment handles, and buy a couple m10 nuts and bolts, but I saved like 100$ for making the swap.

The springs I found a substitute on Amazon as well.

Canada is half imperial and half metric…. My grinder should be too!

 

[DPittman]

I have all the materials required already, the costs for the grinders both with all the material in the lists coming in right at 2300 CAD for me.

I am looking forward to this build. I guess I had no idea that materials would be that expensive.

 

[BaitMaster]

I am looking forward to this build. I guess I had no idea that materials would be that expensive.

Well Jer on his website budgets 1000 US for the grinder and platen attachment. And that was in 2021.

So considering I’m at 1150 CAD per grinder, I’m under his budget from a few years ago by a few hundred dollars per grinder.

if you haven’t read the plans, his grinder design is by no means the cheapest way forward. His design is overbuilt compared to other models in almost every way. I also am using a NEMA premium 2hp TEFC motor, and a quality VFD to boot. So not skimping there.

I bet I could build a bare bones grinder without the features and ruggedness, and without the premium motor and drive for around Half of this one.

But I want to keep it for the foreseeable future, so I’m building a nice one. Professional quality tool.

 

[BaitMaster]

I did some number crunching as it were, and I bet I could have built Jers grinder with a single speed single phase motor and on/off switch with the same hardware otherwise for about 800 dollars if I found a used motor.

But as far as using it would be concerned it would go too slow to really hog metal, and too fast to do nice work on wood or plastic. So there really was no option imho.

I guess I could have skimped on my buddies grinder and gone cheaper but I was thinking along the lines of do unto others what you wish they would do unto you….. and I know he’s going to keep the thing for years and have it as a shop tool, so I didn’t skimp either way. He’s also a body guy So I know for a fact he’s going to be sanding and grinding different materials so I can’t trade him a tool that I know won’t work great for anything….