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PVC Collet Chuck

underdog

underdog

Joined
Oct 5, 2005
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Location
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How do you make a PVC Collet Chuck?

I can't seem to find a "how to" on making a PVC Collet Chuck.

Anyone have a link to one?

Thanks,
 
Last edited:
Not sure why you'd want anything as slick as PVC for the jaws of a chuck, unless you're planning to line 'em.

Since no answer has appeared, I recommend the wooden collet chuck, made by turning a suitable piece of wood along the grain, hollowing the interior to a couple inches in depth, then making saw kerfs to allow it to be compressed by the hose clamp you'll use to exert circumferential pressure. You can make one on a dedicated faceplate, or you can make several of different dimension to be held in a chuck. You pretty much have to use a properly-sized external dovetail in a chuck mount, or you'll have trouble with re-mounting.

Imagine if you have a suitable chuck, you wouldn't be asking, though.
 
A guy on another forum found this (very large- 1mb) article on turning eggs, and a subsequent "how to" on making a PVC chuck. I think it's quite a good design.

http://www.woodturning.co.nz/images/0312p1-32.pdf

I know I've seen some instructions on how to build one a little differently, but just can't seem to unearth it. In fact one fellow I corresponded with swears that the article he saw was in an AAW journal.

I would still like to see those instructions.
 
I'm at work and don't have the book in front of me, but at home I have a book called something like "Turning Ornaments and Eggs". In it there are instructions on making a collet out of PVC, using couplings as I remember. There are several advantages to using PVC over wood but I can't recall what they are other than durability. I think if you rough up the PVC with some corse sandpaper it would give plenty of grip, which was a concern posted above. Haven't tried to make one so I am just passing on what I read, don't flame the messenger. :cool2:
 
I am looking at the same book by Dick Sing. He says the grain of the wood can change the I.D. of the chuck and cause the object in the chuck to turn off center. PVC does not react to moisture and will not have the same effect.

Walt
 
Walt said:
I am looking at the same book by Dick Sing. He says the grain of the wood can change the I.D. of the chuck and cause the object in the chuck to turn off center. PVC does not react to moisture and will not have the same effect.
Click to expand...

Now that is interesting. Obviously this doesn't happen while the wood is in the chuck. Then the next question has to be how opposing jaws expanding or contracting relatively equal distances in opposite directions with change in moisture alter the center, not to mention the difficulty in applying equal circumferential pressure to close the jaws in the first place.

I think that's a place much too far.

Does he mention that the object being held or to be held is subject to the same moisture changes?
 
MichaelMouse said:
........the next question has to be how opposing jaws expanding or contracting relatively equal distances in opposite directions with change in moisture alter the center, not to mention the difficulty in applying equal circumferential pressure to close the jaws in the first place.......
Click to expand...
It's not outside the realm of possibility that wood is not an homogenous material throughout and therefore subject to differential movement (but it does seem as though the relative movement would be very minor).

BTW, even though PVC appears to be a rather "slick" (low friction) material from casual observation, it really isn't. An example that most of us have probably experienced is dry fitting two pieces of PVC together and then having a difficult time separating them. It is probably a combination of cohesion, elasticity, and plasticity. It's also a bit like the friction fit in a Morse taper connection where two smooth polished surfaces provide a high friction connection. So, it is conceivable to me that a two-piece collet chuck could provide a good high friction fit for small parts.

Bill
 
Not to mention a low cost alternative to expensive manufactured chucks, for those of us on a low or non-existent budget. 😀
 
boehme said:
BTW, even though PVC appears to be a rather "slick" (low friction) material from casual observation, it really isn't. An example that most of us have probably experienced is dry fitting two pieces of PVC together and then having a difficult time separating them. It is probably a combination of cohesion, elasticity, and plasticity.
Click to expand...

Smooth surface friction. Not a valid comparison when porous material is used with non-porous. No continuous close contact is possible. However, since friction is the product of coefficient of friction and pressure, holding tight, even with a slick surface is possible.

Wonder if you sealed the rear of the tube you could take advantage of the vacuum. It would help with quick withdrawl attempts, anyway.
 
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