Dan,
I had a similar problem with the bit working loose. I solved it by cleaning the collet. This may work for you. I used a small, cone-shaped brush that is sold for cleaning dental partial plates. It's just the right size for a ¼" collet.
I had a similar problem with the bit working loose. I solved it by cleaning the collet. This may work for you. I used a small, cone-shaped brush that is sold for cleaning dental partial plates. It's just the right size for a ¼" collet.