R8 square holding collet

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Ned Ludd's bro
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I've been doing searches for a while to find R8 square collets to be able to chuck up square lathe bits in my import tool grinder. Obviously it uses R8 collets and have been trying to minimize the collection of different collets as R8 is what my mill drill is. I found out the only collet that seems to come in square is 5c. But I'd never delved into Alibaba and related searches because I was under the impression it's for business only and there are min orders from 10 to 100 pieces.

I did a search on Alibaba and sure enough there were several different co's making square and even hex R8 collets. One outfit had a five piece set, 1/8",1/4",5/16",3/8",1/2". This is exactly what I've been looking for. Now why nobody stocks this I don't know, too specialized?

I guess my question is it sounds like some of you have dealt with these sites like Alibaba and aliexpress direct from China. This says 10piece min. Does this mean I'd have to order two sets of five making 10 pieces or ten sets? Would anybody else want to go in together to buy some pieces?
 
I have never used Alibaba, but have used AliExpress with no issues other than the longer than usual wait for shipping. Also not sure how the recent China tariffs will affect purchases from AliExpress.
 
How about something like this? I found this on the MSC website.

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I have seen instances of mounting square stock in round collets. The required diameter would be 1.414 x the distance across the flats.
 
I have seen instances of mounting square stock in round collets. The required diameter would be 1.414 x the distance across the flats.

Tried that RJ and it was no bueno, even with a full set of R8.

P. Waller's link (thanks for that!)was very interesting but why don't they stock 5/16? I was figuring I'd be good with 1/4", 5/16" and maybe 3/8" as that the size bits I use.......but no 5/16? Zup wit dat? It's crazy I could do all these searches and never come up that site.
 
Tried that RJ and it was no bueno, even with a full set of R8.
Turn a bushing and split it longitudinally. O.D. to fit one of your collets and I.D.to accept your square stock.
This will also work using a three jaw chuck of the bushing has a thick enough wall. The one caveat is that the corners of the stock should be uniform in order to maintain concentricity.
 
Turn a bushing and split it longitudinally. O.D. to fit one of your collets and I.D.to accept your square stock.
This will also work using a three jaw chuck of the bushing has a thick enough wall. The one caveat is that the corners of the stock should be uniform in order to maintain concentricity.

Now that is a great idea. Now why didn't I think of that, d'oh! Thanks.
 
I have never used Alibaba, but have used AliExpress with no issues other than the longer than usual wait for shipping. Also not sure how the recent China tariffs will affect purchases from AliExpress.

As a total noob to both websites and now a bit gun shy of the language barrier after a protracted back and forth with an eBay purchase, I'm leery of jumping in. It is tantalizing as an unrepentant tool freak to see the possibility of my quest being over. But now I'm hyper aware of inconsistency in the advertising. Like the search being for "square R8 collet" and several of the different pictures only having round collets in them. Or saying they have different sizes but can't seem to directly order them.

So I contacted through email, got one reply and said he'd have to check and get back to me tomorrow. My impression is they really want to sell me something but the devil is always in the details. This is not Chinese bashing, this is my understanding of how their long complicated supply lines through brokers and exporters who I'm not sure understand the details of fractions of an inch or mm's and the myriad of different collets works, or doesn't. Hell, I have a hard time when everything is in English, much less trying to translate languages and possibly measurements. Somehow I'm ALWAYS trying to do something that is not mainstream, usually because I'm trying to cut corners or not spend my $$$.

Bottom line is RJ might have come up with a way for my cheap rear to bypass the whole conundrum. We'll see.
 
Now that is a great idea. Now why didn't I think of that, d'oh! Thanks.
I'm glad you pursue that R8 toolholder. If anything like that I helped design, even better, we deserve to pat each other on the back.
Both represent a gigantic trait, inherent in the term Tool Maker.

BTW. Illustration in post #4 TomS is called a toolbit sleeve, sold by many of the suppliers, though some alter the phrase a little. They used to be everywhere, über popular in shopmade boring bars and flycutters. Also offered with internal threads to back-up tool position and adjust.
 
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