Material Choice for Toolholders
I recently acquired an Aloris toolpost and a few holders. I would like to make a few more and wanted to get some ideas on what alloy steel you would recommend. What would have been used by Aloris? Is there any need to heat treat? I realize there will be many that try to talk me in to just buying some because of the cheap and inexpensive imports and I'm sure I will try a few. This is less about the money and more about the challenge and learning. Any tips or thoughts are always greatly appreciated. I plan to use my shaper to cut the dovetails all at once and then will saw them to size. Probably clean up and finish on my shaper (I don't have my mill up and running yet).
I think this was discussed a month or so back...
Still, I'd reccomend plain old hot rolled low carbon steel. Yes, half hard or 4140 would be stronger, but plain steel should be more than enough for home shop use
I've searched for about an hour and can't find much on material choice. I have some mild steel that I may give a go with. I figured that if I'm going to do it I might as well make them with a good material.
I like 12L14. Easy to machine, cheap. I'd use 1144 if I could find it any way but round.
I know you want to make them, but don't go paying to much for the steel when the tool holders are only $8-$10 each to buy.
Making quick-change tool holders.
Learning how to make these is definitely worth the trouble. After making a few on the Mill, I now buy the ones from CDCO. Making them in longer strips on the shaper has some other advantages. There are some applications that it would be nice to have the freedom to extend the standard tool holders. For instance it would be easy to make your own holders for parting blades, swing-threading tools etc. I have used 12L14 and it has worked OK. On the shaper you can actually use the QCTP for trial fitting your dovetail.
I made a few for the MH 90 posts on the Clausing/Metosa lathes at
school out of aluminium. The original intent was to see if it could be
made but when I was finished with the peice I went on and made a
few holders for 3/8" bits and so far they have worked fine for light
cuts and threading. So unless youre into hogging a lot of material
off it shouldn't matter what the holder is made of. :-)
I don't think material for holders is a big concern. I made holders from mild steel several years ago and they're holding up fine. (I probably wouldn't do this again because the low cost holders are now available.)
I made my most used holder, a tangential, from aluminum and it works well too. Its surface is a little beat up now from 5 years of frequent use but it works as well as ever.
I also made a DTI holder from aluminum and it sees a lot of use too - well worth the effort.
One benefit of making your own is you can make some holders that you can't easily purchase, e.g. a retracting type.
Edit: The expensive part of the retracting toolholder is Thomas' book but it is well worth the cost, he's a natural teacher of machining techniques as well as a gifted designer. Material cost for mine was $7 plus some small scrap for the round parts. There is an adjustable over-center mechanism that locks the tool in the forward position. Not sure if Hemingway's instructions are a copy of Thomas' article, they used to tell you to buy his book.
More on my build: http://www.gadgetbuilder.com/ToolHol...tml#Retracting
Last edited by GadgetBuilder; 01-21-2011 at 01:33 PM.
Thanks for the input. A large part of why I want to make these is in learning to cut dovetails on my shaper. There are also holders I am planning to make that aren't as cheap or common. Of course thanks to John I now have a few more on that list. I like the retracting holder. Once extended back to cutting position does it have a lock to keep it from moving back during the cut? I noticed that Hemingway sells kits. Is there any trouble purchasing through them being I'm in US? I had my eyes on other kits from them. Anyone know the conversion rate to dollars so I can get idea of my price?
I have made several of my own. Some are CRS, some are 1/2 hard 4140. I like the 4140 ones the best, even though the CRS ones work just as well. It's good to have extended ones to reach past a live center. I really like the retractable threading one shown above. I will probably make one of those at some point. It's best to leave a larger space in the middle of the clamp screws to allow for the vertical adjustment nut. I made my first ones evenly spaced and now it's hard to get to those middle ones to tighten or loosen.
Last edited by Toolguy; 01-21-2011 at 11:41 AM.