Originally Posted by
bradywatson
1) Send them back.
2) Order the correct ER25 Fractional collets from either ShopBot or Precision Drive Systems.
El cheapo collets or collets that do BOTH fractional and metric, are a BIG no-no on HSD & Colombo spindles. There is not enough thread to fully collapse these collets, and you will add your name to the list of people who found this out the hard way...by needing to use a cut off wheel to cut the nut off of the end of the spindle because you can't get it back off again...even with a cheater bar.
-B