Collet question

[sco]

This question is about my 2mm ER20 collet.
When I first started milling, I had no problems with breaking my 2mm bits. I cut heaps of stuff.
I was doing cuts through hardwood ply at around 12000rpm depth of about 3.5mm (approx 1/8 inch) and feed speed of 300mm/minute (12inch/min)
and all was well.

One day I was milling and I pushed the envelope too far and snapped the bit. Which in turn, damaged the collet a very small amount. It doesn't have that nice square opening anymore, although it doesn't really look all that bad. Since then, I have been snapping bits like crazy!
I am now getting a bit suspisious about the collet.
Do you think that it could be the culprit with regards to snapping my 2mm bits?

cheers
rosco

[Big-tex]

It is possible but unlikely. Is your collet pricey? If not replace it and test at normal feeds and speeds. Please post picture of damaged piece.