Small Chuck

[Manderioli]

I am looking for recommendations on a small chuck (less than 6") so I can produce and hold aluminum rings. The problem currently is the 6" chuck jaws do not have a small enough diameter to fit internally on a ring.

My 6" chuck is mounted to an adapter which threads onto the SB spindle nose.

Should I consider a 3 or 4" chuck with an adatper or consider a chuck that would directly thread onto the spindle? A pro/con comparision would help me determine the best solution.

I am currently sitting around 0.0005" run-out on SB spindle.

 

[Al 1]

What size are the finished rings? Al.

 

[Manderioli]

The range of IDs I current need to hold is from 35mm up to 80mm.

Bison sells this chuck:
http://www.bisonchucksonline.com/Bison/Bison-Universal-Chuck-4Inch-3Jaw-112Threaded-Solid.htm

 

[Al 1]

Wall thickness?

 

[Manderioli]

Smallest will be 3mm and largest 6mm.

 

[RJSakowski]

One of my 5" chucks will hold a 34mm i.d., the other a 37-38 mm i.d.

 

[Manderioli]

I should note these aluminum rings are 3-6mm wall thickness and also same range of thickness.

 

[Al 1]

How would you hold them without distorting?

 

[MrWhoopee]

Because of the thin wall, I would recommend making an aluminum expanding mandrel for each size, perhaps one with multiple steps for different sizes. How many are you making and is this a recurring job?

 

[Manderioli]

For now I am only prototyping. Distortion is not bad since the rings are being made from solid billet 100 (4”) diameter sections typically thicker than finished dimensions. When wall thickness becomes small, I will slow the lathe down and take smaller depth of cuts.

I have considered making custom mandrel/adapter for the two smallest rings. The goal is to only prototype the concept then have everything outsourced with cnc capabilities for production.