Pin chuck query

[Normancb]

Does anyone have any experience with using a pin chuck to turn closed-end pens? Have seen references to them in a few places so I thought I'd give it a try. I took a spare mandrel and milled a flat 3/32" deep on it to take a bit of 3/32" steel rod. It fits nicely into a 7mm tube but won't lock - all that happens is that the mandrel spins and the rod spins the opposite way like a roller bearing, while the tube stays still. I tried using a bit of rubber instead of the rod and that locks but is very "bouncy" so gives a poor surface finish from a skew. I've used home made pin chucks on wood before now and they seem to work fine.

Any advice gratefully received.

 

[KevinMc]

Hi [MENTION=297]Normancb[/MENTION]

Is the information your looking for included in this forums tutorials?

http://www.penturners.co.uk/misc/pdf/70_Tips/Mandrel_for_Closed_End_Pen.pdf

Kevin

 

[flexi]

I have a few....i bought mine through Turners Retreat ( craft supplies) a quick flick and it locks straight up.....

 

[Penpal]

There now for those that can and the ones that would prefer to buy. A ready made answer to help along the way. By the time turners decide to do this when making as much of the pen that seems practical the skill of making a mandrel is a doddle in the park compared with threading etc.Also thoroughly gone over in the IAP Library.
Peter.

 

[wm460]

Just to complicate the matter.

http://content.penturners.org/library/tools_and_jigs/pinchuck.pdf

 

[Normancb]

Thanks to everyone who responded - some useful information.

Experimenting a bit further, it seems like the critical thing is that the mandrel has to be a very close fit in the tube for these things to work. The one I made first used a commercial mandrel shaft which seemed to be a close fit but whatever size pin or pin material I used it always would just spin with the pin rotating and the tube not driven. I made a new one by using some 0.25” rod and machining it down till it was just a sliding fit in the pen tube and it works fine with a 3/32” pin. There must be an interesting bit of maths there but I’m happy enough that I made it work. Surprisingly, Turners Retreat no longer lists them. They are still available from Craft supplies in the US but the postage cost more than the item.