I ordered a collet or adapter bushing to allow for 1/8 inch shanks to fit in my Ryobi Trimmer Router. My router holds 1/4 inch shanks. In short, I had to add three grooves with a dremel tool and now the collet holds the 1/8 inch shanks.

The first collet was a one slit type and it did not hold the 1/8 inch shanks.

I ordered a second collet and I was assured it was a collet that had a slit and 2 other grooves and it would hold the 1/8 inch shanks. It turned out to be another one slit collet and the Ryobi still could not grip the collet well enough to hold the smaller 1/8 inch shanks.

I added a few extra grooves to the collet with a dremel tool and that worked. I added 2 extra grooves to one and three grooves to the other. The the three groove collet is probably a little better but both hold the bits tightly.

I have not cut with them yet.

Bill J.