Material for HomeMade End mill holders

[KEJR]

Hello,

I'm looking to make up some 3/4" straight shank set screw endmill holders. They would be basically like the tormach set screw holders, but not hardened and ground. I like the tormach holders and have a couple, just looking for an excuse to use the new lathe for something useful!

Is there a suitable material for making these that will hold up to home shop occassional use? I'd prefer not to heat treat since I don't have a real good way of grinding these when done. I have a 10" hunk of normalized 4340 rod that is leftover from a custom axle. Its properties seem pretty good compared to other steels until you get into tool steel.

If there really isnt' a suitable (non hardened ) steel for end mill holders I'll just make up some holders for non critical things like tap guides and indicator holders, etc.

Thanks!

KEJR

[Boucher]

If you have not used any 1144 Stressproof you should try it. It is a joy to work with. I use a fair amount of 4130 and 4340 which have nice properties, just not as easy to work with as the Stressproof and leaded steels. That said it is important to use the right material for the job at hand. A lot of tools in the home shop don't see the wear and abuse of the commercial environment and don't have to be strong. The other side of that coin is that if you are going to put in the machine time it is wasted if it doesn't have an adequate life.

[KEJR]

Boucher:

Yeah, I just looked up the stressproof. Very high marks on machineability and decent strength/hardness. didn't look as hard or strong as the 4340.

Good point regarding being careful what you put your time into making less durable parts. I'll have to consider if I just want to make stuff for the less critical things like the indicator holder, etc.

[lane]

I make all of mine out of pre Heat Treated 4140 are ETD 150 will las for ever and don`t have to worry about them bending.

[J Tiers]

For homeshop use, by a reasonably careful user who won't try to force a swarf-covered Em into the hole, and who WILL keep the hole clean, anything that you can turn to shape is fine.

CRS, Stressproof, whatever you have that you can cut. I might leave out hot rolled 1018, only because it can be gummy and a pain to work.

I agree with lane, I also like making that sort of thing out of pre-hardened 4140, but it can be more of a problem to cut. And truthfully, I have one mill arbor that is 4140, and one that is CRS, they get used about the same amount, and they both look and work fine.

Maybe I;d see more difference in an end mill holder, just because of the way swarf collects around and wants to get into the hole.

[philbur]

Use what ever steel you have to hand that is reasonably easy to machine.

When it only last 50 years of home shop use instead of 80 your great grandson can take 20 minutes and make a replacement.

Phil

[KEJR]

Thanks guys,

I appreciate the reality check. I just checked and the 4340 I already have is pretty tough stuff I only have to turn from 1.125" down to 0.750 for about 1-1.5" length and then drill/bore/ream for the tool. I think even thought this is not great machining stuff that with HSS or carbide I should be OK. 4142Prehard seems to be about 10% better in the machinability department than 4340 so maybe that is what I'll use when the 4340 is used up.

Thanks,
KEJR

[KEJR]

When it only last 50 years of home shop use instead of 80 your great grandson can take 20 minutes and make a replacement.

Ha ha ha. Nice one Phil! I don't want the great grandkids to think their old gramps was a total schmuck though, so I will try to make them as tough as reasonably possible. Or maybe I'll just let out a ratchety old rant that the darn kids don't treat tools the way we did back in the old days... You know when they still had manual machine tools and burned oil for heat and electricity.

Thanks for the laugh!

KEJR