Chuck and tail stock for home made rotary available to purchase

I built my own rotary and it works very well. The key for me was the home made self centring chuck. It makes a huge difference. The base is standard extrusion and some home made laser cut and 3D printed parts. The tail stock is height adjustable and can apply inward pressure on the item to avoid having to use too much clamping force. Max opening is about 110mm, but I can redesign for larger. If any one is interested I could put together a price for the printed tail stock and the chuck parts. Let me know. Certainly my parts would be less that £50. Delivered in the UK, elsewhere I could check. My intention is not to sell a whole rotary attachment, but more to help you build your own. Unless of course you would like that?



1 Like

Hello there David, nice work.
Can you please explain the mechanism which keeps the chuck’s jaws always centered in relation to the rotating A axis for preventing the rotating thing from wobbling?

Thank you.

You can tell from the picture - it’s two pieces of acrylic with arc-slots cut into them in opposing directions. When you rotate one of the pieces, the intersection points of the arcs will move inward or outward, so all the rubber holders will be at the same radius.

I thought so but then i saw the jaws in the middle of the arcs which should prevent them from sliding by counter rotating the discs. maybe you need to manually push /pool the jaws instead of rotating the discs

i think. not sure.

Hi Squid
Oz is correct, the action of rotating one disk in relation to the other moves the buttons smoothly towards and away from the centre. The buttons are effectively trapped in a pocket formed by the intersecting arcs and remain in position when you lock the disks by tightening any one of the buttons in place.



Search for “Longworth chuck”.

EDIT: I was able to do this in LB with very minor modifications to the instructions. Layers and node editor are your friend.


Interesting. I wasn’t familiar with this mechanism.
from your pictures i was speculating that when the buttons are at the center of two intersecting arcs they might get locked in place cause the rotation might force them against the tangent of the arcs. probably wrong assumption. i watched the video - very nice.

We get smarter everyday.

Downloaded a dxf of this fun toy, loaded to lightburn and counter rotated one disc and it couldn’t be any clearer how this thing works.

Me like!

1 Like

I’ve apparently been building stuff for too long. I’ve never actually seen one of those before (at least, not that I remember) but intuitively understood how it worked just from looking at the picture. The link to the tutorial is useful too - I suspect it would actually be simpler to make that in LightBurn that in InkScape, looking at the steps.

It reminds me of iris mechanisms.

Yes, I do a lot of wood turning so came across this idea some time ago and it was an obvious choice for the rotary. I drew it up in Fusion 360 and laser cut it in 6mm acrylic.

So all you need now is the tail stock assy:-)
And of course an adaptor to fit to the stepper shaft