Soft Jaws to hold cylinder

[GiroDyno]

Can you make a plug to go inside the tube to prevent it from distorting where you clamp it?
Sacrificial aluminum fixture block with a hole bored into it, cut a slot to pinch it. Underside of the cap can rest on the block to hold it square, since the fixture is aluminum you should be able to drill or mill or undercut through your cap and into the fixture without causing a fuss.

 

[drcoelho]

Here are some images of the part. Need to hold it by the smaller cylinder, and need to machine the holes from the top face of bigger cylinder. There are some counterbored holes and also some tapped holes. The cylindrical parts will be pre-machined on lathe and will be exact, just need to machine the holes.

 

[drcoelho]

Dimensions: small cylinder 65mm diameter / 25mm height, large cylinder 170mm diameter / 25mm height

 

[guythatbrews]

Best way toe clamp down on 123 blocks or support rim and use a chuck. Holding on the short hub is about the worst way.

 

[EmGo]

Aluminum pie jaws in a regular chuck set flat on the table, just drill relief holes in the jaws where your thru-holes will go.

Yes, hold by the big diameter, not that stinky little stub.

 

[DanielG]

If you go with a 3/6 jaw chuck, get one that you can bolt right down to your T-slots. It's much easier than messing around with clamps.

If you don't have a chuck that's big enough and you just have one of these to do, I second the 123 block option. Just put them where the holes aren't and clamp the thing down.

 

[604Pook]

Best way toe clamp down on 123 blocks or support rim and use a chuck. Holding on the short hub is about the worst way.

x2 Plenty of space for toe clamps between those holes. or use something like these https://www.octaneworkholding.com/products/ignite-clamp , with some shim stock or something machined to the OD to not make the sides.