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Any body make their own collets?

I recently picked up a little cutter grinder that takes the elusive 16mm collets. I got two with the machine, one is a .250" and the other looks to be about the same size, but is a blank that hasn't been split yet. Since collets are near to impossible to get I am thinking about trying to make a few. In my mind rough turn on the late and finish grind with a tool post grinder.
Am I showing my lack of experience here, or does it sound doable? I made an er collet chuck a couple years ago, and it went pretty good......
 

gerritv

Gerrit
I would say it is very doable.
I have an Alexander 2CGD, it takes the larger collets. But of course the wheel hubs are unobtainable so made 12 of them.
IMG_20190526_164904.jpg
 

RobinHood

Ultra Member
Should work fine. Hopefully you can finish grind the critical areas in one set-up to preserve concentricity.

869BE6FD-110B-4EAC-9A44-E1161B3643F4.jpeg
 

Tom Kitta

Ultra Member
I recently picked up a little cutter grinder that takes the elusive 16mm collets. I got two with the machine, one is a .250" and the other looks to be about the same size, but is a blank that hasn't been split yet. Since collets are near to impossible to get I am thinking about trying to make a few. In my mind rough turn on the late and finish grind with a tool post grinder.
Am I showing my lack of experience here, or does it sound doable? I made an er collet chuck a couple years ago, and it went pretty good......

Depends on collet geometry of how easy they are to make.

Why don't you convert to ER16 collet system? Usually it is far easer to modify for other collets then make your own collets.

I made ER40 chuck from scratch and it is very precise. Roughly within collet themselves precision.
 

Mcgyver

Ultra Member
If another human made it you can....otoh depends where you are in life and how you want to spend your days. Once I would be geared up to do so so prove to myself I could, now it'd be flogging the thing on kijiji and buying one with all bits and pieces. To make them "properly" is big endeavor - tool steel, rough machine, HT, grind.....figure out how to finish the tiny bores in hardened tool steel lol

A middle of the road idea would be just turn them from mild steel or even better 1144 and don't worry splitting them. Make the body to fit the workhead, turn the OD and drill/ream a hole at the same setting for concentricty, then hold the tool in it with a set screw. You might be some fraction of a thou less concentric than with a split collet but good enough for most T&CG work (yeah, its grinding, but it would be rare to have to work to as small a tolerance as surface or cylindrical grinding). You likely only need 2 or 3 additional sizes to fit the common fraction sizes you'll encounter.
 
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Thanks for the replies guys, I too think it should be doable. As to why, well, I am still learning and the only thing I have learned by doing nothing is that I don't like being bored. This past winter I broke a gear in the feedbox on my 1929 South Bend, so I made a gear cutting attachment for the shaper and made my own. I enjoyed the challenge and learned a little in the process, and gained quite a bit of confidence while at it.
As to selling and buying another, I would just be handing the problem to someone else and this is the first one I have seen since I started half heartedly looking a couple years ago....
 

gerritv

Gerrit
U2 collets are unfortunately 20mm, not 16 and likely different collet angle as well.
I would make one with the max 12mm hole (no slitting) as McGyver suggested, then use an ER16 straight shank chuck for everything else. If you are ambitious make one with an ER16 head on it. If you can get the blank centred well in a 5C collet or in a 4 jaw, then that should result in 'close enough' runout.


L20's are also known as U2 and E355 with likely som detail differences.

Gerrit

Quote "The cutter to be sharpened was secured in, on early models, an unknown type of collet with a 16 mm shank that had a maximum capacity of 1/2" (12 mm). Later (and by far the more common type) used what the makers listed as a Schaublin Type L20 with a 5/8" capacity (17 mm), collet angle being 15-degrees and the thread 19.7 x 2 and 45/5 degrees. Hence, as the early collets are now unobtainable (though they can be specially made), before buying one of these machines (or ordering new collets) do check what the situation is, An early model without a complete set of collets, or with ones that are worn, will be very expensive to rectify - and should be far cheaper to buy than one fully equipped. A further problem arises with regard to the later collets sold around the world as the Type U2 and often listed as being: "suitable for Alexander and Deckel grinders". Owners report that these fit the Alexander version, but not the Deckel - or the threads, at least, are different. " from lathes.co.uk
 

gerritv

Gerrit
L20/U2 collets from AliExpress are excellent quality, at a considerably lower cost. Niels is not the best option for hobbyists :) although I often oogle through his wares. In this case his price is fair but.....
 

Dabbler

ersatz engineer
I love those Wolhaupter boring heads on Nielsmachines... but only after coming into a very large inheritance, or similar windfall. :eek:
 

a smile

Lifelong hobby - cold iron
Premium Member
I would say it is very doable.
I have an Alexander 2CGD, it takes the larger collets. But of course the wheel hubs are unobtainable so made 12 of them.
View attachment 15662
Yes, too many parts will not be able to buy the problem, need to make their own, so the purchase of machine tools and equipment to have their own production of some parts of the psychological preparation ------------
 

trevj

Ultra Member
I love those Wolhaupter boring heads on Nielsmachines... but only after coming into a very large inheritance, or similar windfall. :eek:
I managed to find a quite affordable UPA2 (MT2 shank)and a UPA1 (3/4" straight shank), on ebay, though admittedly, it did take some time watching.
The UPA2 came cheap as it was wearing a badly done straight shank adapter that you could 'just' see in the one picture, was over the original shank.
Nielsmachines has some great eye candy, but at sometimes eye-watering prices!

As to the OP's issue, I am cheap and a simple man.... :) I'd make the basic collet shape in brass or aluminum, bore it to size, and make a single cross slit almost all the way to the back so it closed down when the nut is tightened. If feeling REALLY keen, put a plug in the bore, flip it end for end, and index it 90 degrees to the first cut, and make a cut the is almost all the way to the front! Hardened? Nope. Never gonna use it enough to wear it out anyways, and if you do, it's a few minute job to make a new one!
 
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