# Pin or expansion chuck?



## Carl Fisher (Oct 30, 2013)

Ok, so I'm tired of rigging ways to make closed end and kitless pens.  I can't rely on a collet chuck alone for profiles that are not straight.  So I'm looking for a blind mandrel system of some sorts.

Any pros and cons to each style?  

I'm thinking ultimately of having 2 pen styles of internal profile.  #5 nib and rollerball sized pens and #6 nib sized fountain pens.  But I'd also like the flexibility of being able to use them on tubed (kit) pens.

I expect an expansion chuck will be able to be used on a slightly larger range of ID hole sizes from a single chuck?


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## Ed McDonnell (Oct 30, 2013)

I'm not sure what you are thinking about when you say "expansion chuck" with respect to pens.  The closed end mandrels sold by AS?

For kitless, I find a set of rods (one female, one male) threaded to match the cap thread that I can hold in a collet chuck to be a good solution.  It's also affordable since I can make them on my metal lathe ("affordable" of course ignores the sunk cost of the metal lathe, tooling..... :biggrin.  I use the tailstock as long as possible to prevent breaking the threads for more "delicate" resins.  This is a very accurate approach and it is what I used for my carved blanks.

The expanding closed end mandrels sold by AS are intended for one size hole (specific kit pens).  There is no range for them.  However, I have on occasion made delrin sleeves that I made to get them to work in a smaller than intended hole.  My biggest gripe with these are that the design results in them failing to tighten up sometimes.  My second biggest gripe was that they didn't have cap size mandrels for all the larger kits I was interested in.

Pin chucks are great if you have the ability to make them yourself.  Not the most precise solution, but good enough for most pen tasks.  Make one for each size hole you are working with.

That's my view of the world (which may or may not match anybody else's view).

Ed


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## Bruce markwardt (Oct 30, 2013)

What I do for my kitless pens is use a collet chuck as follows - Take a 4 or 5 inch long piece of 1/2" aluminum rod, which you can buy at Lowe's, or online.  Turn the rod down (carbide tools work fine on a wood lathe) so it will fit inside the body of the pen you are going to be making.  Since you should know your drill sizes and depths, that's where you start.  

Thread the side of the rod closest to the collet chuck using your die.

Now you can drill your blank using a collet chuck or pen chuck.  Thread the blank.  Mount the aluminum rod in the collet chuck.  Thread the pen body onto the threads you've cut into the aluminum.  Turn the body as you'd like.

I have a pin chuck, but have found this method to be much more secure.  It's also cheap.  I suspect the aluminum odd would bend if you applied enough pressure, but I haven't found this to be a problem.

I've made a similar rod for my caps.


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## walshjp17 (Oct 30, 2013)

If you don't wish to make your own pin chucks, talk with Rick Herrell (rherrell).  He makes a number of pin chucks for tubed pens - just supply him a set of tubes and he'll build a set of pin chucks at a quite reasonable price. 

As for non-tubed pin chucks/mandrels, you may want to give Rick dimensions to see what he can come up with.

Full disclosure:  I am one of Rick's satisfied customers.


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## PWL (Oct 30, 2013)

+1 on Rick
Paul


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## Carl Fisher (Oct 30, 2013)

I'm a happy Rick customer as well.  However I was hoping to find a chuck that would for example work for a tube-in 10.5mm body as well as an non-tube version for kitless.  It sounds like the expanding style won't fill this need any more than a pin chuck.  

I really don't want to have 8 different mandrels to accommodate everything I want to use them for...was hoping to get by with 4 (2 body sizes, 2 cap sizes)


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## Carl Fisher (Oct 31, 2013)

Well, after combing through the common tube sizes for all the kits, it looks like I can get away with 6 pin chucks to fit every pen I could possibly want to turn.  I'll just adjust my kitless drilling to fit the chucks and all will be good.

10mm, 10.5mm, 15/32, 12.5mm, 31/64, 33/64 should fill 90% of anything you'd want a blind mandrel for except for the few odd ducks in the really big pens.


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## randyrls (Oct 31, 2013)

Carl;  Be very careful.  I ordered a "blind hole expansion chuck" from MSC, and the adjustment screw is on the blind end of the chuck.  So how do you tighten up the chuck??


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## 08K.80 (Oct 31, 2013)

randyrls said:


> Carl; Be very careful. I ordered a "blind hole expansion chuck" from MSC, and the adjustment screw is on the blind end of the chuck. So how do you tighten up the chuck??


 

Let the seeing eye dog use it??:wink::biggrin:


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## jimjam66 (Nov 3, 2013)

I use pin chucks because they're easy to make and aluminium rod is cheap.  That way you can have as many as you like! :smile-big:


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## edstreet (Nov 3, 2013)

Carl,

Something like this you mean?






In use.
12mm x 0.8 threading on the lathe. Material is ebonite and brass. - YouTube


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## Jim Burr (Nov 3, 2013)

Expansions chuck. Mine are from AS...work great and are easy to use. A bad point is the are a bit spendy, good point...they work well for me. Others will have other experience...I have mine.


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