An ER collet setup question

[Makintrax73]

I was setting up a mini crankshaft in an ER 32 collet this morning. It occurred to me that I should clean the swarf out of the collet and holder.

Also occurred to me I don't know what the reference surface is in the collet? Is it the inside of the cap? Or is it the inside angle of the body of the holder that determines how the collet seats? Or both? Seems like swarf builds in the cap in hard to reach spots.

Mostly curious but I figure if one is more important I should concentrate my swarf cleaning to the important surface.

 

[verbotenwhisky]

Its the taper on the inside of the body, I actually bought a cap with a thrust bearing in it so tightening the cap doesn't try to spin the collet in the taper....

https://www.buyustools.com/wp-content/uploads/2020/08/ER32-bearing-collet-nut-5-scaled.jpg