Lathe Tool Holders

[David2011]

I have had very good results with Accusize tooling, they are a Canadian company with good stuff at, generally speaking, reasonable pricing.

I’ve been happy with Accusize as well. I also got a set of VerLich tools from Amazon. The holders are very satisfactory. The inserts are OK. When I got ISCAR inserts with the IC907 coating the quality of finish drastically improved. That coating along with the geometry of the inserts is perfect for small lathes. They work well with lighter depths of cut and slower feed rates than any carbide I’ve tried. Little Machine Shop has a speeds and feeds calculator that is well suited for small machines and tooling. You will not get good finishes without adjusting your feed and spindle speed to the size and type of material you’re cutting. I still use HSS bits that I grind myself for many applications.

As Verbotenwhisky mentioned, getting a cutoff TOOL (not tool holder) square to the workpiece is critical. I realized that while the holder was square to the work, the tool was crooked in the holder by a few thousandths. Correcting the discrepancy made a huge difference in the surface finish that I was getting when parting off. I’m still using a HSS parting tool. I keep it sharp and find that it cuts best if set just a hair’s breadth below center.

 

[Dabbler]

I keep it sharp and find that it cuts best if set just a hair’s breadth below center.

That is my experience as well. about .003 below is what has worked for me. My thought is that it prevents the tool from digging in - when there is flex, the tool cuts shallower. This would need a magnified high speed camera, which I don't have. (shucks)

 

[verbotenwhisky]

I recently swung back the other way and started looking for a HSS solution for general turning instead of carbide. I messed around with a few different HSS tool holder designs to find something that could meet these requirements:

1. Easy to sharpen w/ repeatable results and no complex shapes
2. Able to be sharpened while the tool is still in the AXA block or is otherwise able to be "indexed" so that tool height remains unchanged
3. Able to turn and face with the tool post at 90 degrees
4. Great surface finish in a variety of materials

I tried AR Warner's HSS inserts in a standard CCMT tool holder first and they didn't quite hit the mark. They met 1, 2, and 3 but failed pretty hard at 4. Brass was about all it left a good finish in.

Next I made a knock off of the Wimberley tool holder. It was fairly easy to make with a tilt vise and meets 1, 2, 3 and mostly 4. You can sharpen it right in the tool block and Wimberley has a creative way to return the blank to the same height without messing with the height of the tool block. The downsides are it takes up a lot of real estate in front of the tool post and fouls on the body of a regular length live center. You also have only one choice of rake angle since it's built into the holder. Wimberley's is about 15 degrees and is a compromise to fit a range of materials.

I then made a tangential tool holder of the same style as most DIY's. It meets all 4 requirements and takes up a lot less room up front. I made this one so I could level the tip of the blank with the top of the tool holder and set the AXA holder's height based on that position. After sharpening I can just line the tip back up with the top of the tool holder using the bottom of the sharpening jig or something else that's flat and it's ready to go. Rake angle is based on the grinding jig you use and you can have a different grind on each end of the blank. Like the Wimberley style holder it's easy to make with a tilt vise but there are a few more steps involved.

I very much like the Tangential tool holder, the other looks good, very nice work.

 

[tcooper27]

When I got ISCAR inserts with the IC907 coating the quality of finish drastically improved. That coating along with the geometry of the inserts is perfect for small lathes. They work well with lighter depths of cut and slower feed rates than any carbide I’ve tried.

Where do you buy from? I'd like to try some CCMT ones for my boring bars next time I need to restock. Prices look all over the map.

 

[David2011]

I got a screaming deal from a surplus company. Correction to the previous post- the grade is IC807; not IC907. The IC807 is good for most metals. They were about $15/box and only had 3 so I got them all. When I get low I’ll just have to hunt for the best price at the time and pony up. I’m using DCMT070204 inserts.

For roughing I’ve been using Oscarbide TCMT32.51/TCMT16T304 inserts that fit the common inexpensive 1/2” sets of holders. I haven’t found any magic combination of speed and feed to get a great finish but they’re durable for breaking through a factory or weathered surface and seldom chip.

I’ve set the roughing and finish inserts up in holders so they are very close to the same DOC and left projection. I just make a sq inside corner with the smaller nosed insert, remove it from the QCTP and set the larger tool and holder on the QCTP with the set screws loosened slightly. The nose is moved into the corner and the set screws tightened. It’s close enough that I don’t have to reset the dials; just keep on cutting. I measure frequently because the cross slide screw is not a perfect match to the markings on its dial.