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Chris165
07-28-2012, 11:03 PM
I havent been in the shop in a while due to a career change. Was finally out there today cleaning things up and found some Valenite 1" and 1 1/4" shank indexable turning toolholders. The QCTP I have is a CXA with 3/4" capacity. When I purchased the toolholders I was going to bring them to a friend with a big manual mill to plow them down for me.Figured I would try to do it myself with my X1, that was horrible. So the next best thing was to try the lathe. I put a Palmgren rotary table milling attachment with a vise attached on the cross slide and a 1/2" carbide end mill in the chuck. The tool holder shanks are really hard but the end mill cut. the shank seemed to work harden as I was cutting it and it just started to rotate the milling attachment instead of cutting. The lathe is a 1929 16" South Bend with bronze headstock bearings. What I'm thinking of doing is picking up a 1" shank 1.5" indexable face mill from the local industrial surplus store and plowing off around 1/8" at a time. My question is will this work or will it harm the lathe. The previous owner of the lathe ran a 2" boring head in the chuck, but I dont know how the forces on the chuck compare from a boring head to a face mill.

dalee100
07-28-2012, 11:44 PM
Hi,

Taking .125" in one pass is a lot to expect from trying to mill in a lathe. Even a Bridgeport might get a little balky at such a cut. Milling in a lathe with an attachment is considered light duty. I'd start out trying to take maybe .025 or .030" per pass and see how it does.

dalee

Uncle O
07-29-2012, 07:32 AM
Some of those tool holders are made from tough, heat treated material.
Really all you can do is try, then adjust your effort to how the machine responds and the material yields.

Chris165
07-29-2012, 09:16 AM
Hi,

Taking .125" in one pass is a lot to expect from trying to mill in a lathe. Even a Bridgeport might get a little balky at such a cut. Milling in a lathe with an attachment is considered light duty. I'd start out trying to take maybe .025 or .030" per pass and see how it does.

dalee

Sorry about that, I did not mean .125" deep. I was going to take a .125" wide cut at .025-.030 D.O.C. and see how it works. Would an indexable face mill or an indexable end mill be better for this application? Is there any reccomendation on round or the typical square or triangle inserts? Glacern has some face mills with round inserts and they say that it reduces the cutting forces and vibration. If my lathe will handle a 2" face mill I might look at making a more ridgid milling set-up. The current set-up is using a Palmgren rotary table milling attachment which I can't seem to find any manufacturer info on. The only ones I've seen from them just have a vise. That would probably be the way to go.

vpt
07-29-2012, 01:02 PM
I mill stuff all the time on my little atlas lathe. Yes very light cuts (you have to feel it out). I've been able to take as deep as .100 in mild but just roughing cuts. With small 4 flute endmills I have been able to take nearly .200" in aluminum.

It has worked for everything I needed so far but I do want a real mill some day.

This is nearly .100" in one of the tool holders I was making.

http://www.youtube.com/watch?v=P0vk2SQRQnQ&list=UUjGabqSas3YXEXyT-AmpRNw&index=7&feature=plcp

dalee100
07-29-2012, 01:19 PM
Hi,

I think insert face mills while getting pretty darned good for power needs, still they need more power than a good sharp endmill. I would be inclined to try a solid carbide end mill. Because I agree with Uncle O, commercial tools are made from tougher tool steels that are often hardened a bit for increased wear.

Have you considered that your setup isn't rigid enough? I would be inclined to just build a stack of solid material and clamp to that for the best stiffness.

dalee

Chris165
08-04-2012, 06:29 PM
I ended up using a cobalt bandsaw blade to rough them out and finish with a grinder because I needed the tools for the job I was working on. The remaining toolholders I will try using a nice new sharp endmill. Need to get a straight shank endmill holder that I can clamp in the chuck. Were you guys using a rougher or a regular e.m.? I'm also looking at making a more ridgid milling set-up for the lathe. Thanks, Chris

dalee100
08-05-2012, 12:38 PM
Hi,

Sometimes any port in a hurry.:)

I wouldn't be overly concerned about rougher or regular endmill. I would just use a regular one simply because it's cheaper to buy and easier for me to resharpen. Roughers are really only valuable when taking heavy cuts.

dalee

metalmagpie
08-05-2012, 09:10 PM
I've seen guys directly mill a female dovetail in the big turning tool and put it directly on their QC toolpost. No toolholder needed.

I understand that there is a CXA toolholder which will hold a 1" shank also. It's a special version of no. 1 I believe.

metalmagpie