Centering aid for polygonal stock

[Paul Jones]

Marv, The Home Engineer and Ralph,

I added mandrel mountings to the back of a couple of my smaller 3-Jaw and 4-Jaw chucks for mounting into my larger 6-Jaw Adjust True chuck. I use the smaller chucks for holding diameters too small for the larger chucks (see http://www.homemadetools.net/forum/c...4848#post80696 and http://www.homemadetools.net/forum/c...0262#post72147 ). Another great technique is using a high precision ER32 collet chuck mounted in the 6-Jaw chuck for very precise 2nd operation work (see http://www.homemadetools.net/forum/e...aw-chuck-65548 ). The error in the chuck and collect chuck tend to cancel each other out within typically around 0.0002" to 0.0003" TIR depending on how much time you spend initially making the Adjust Tru adjustments to the 6-jaw chuck.

Regards,

Paul