[Cherryville Chuck]

I don’t have access to mine right now but it was either 19 or 20 mm by 1mm thread pitch. I’m leaning towards 20 mm as the right diameter. It’s the same as a bunch of DWs, Hitachi m12V2, m12vc, m12ve, plus I think the newer Makitas. It is a very common collet but most Sears routers were made by Ryobi (315.xxxxx) and I haven’t seen any Ryobis with that collet but maybe the newer ones use it.

 

[Cherryville Chuck]

I took the collet off my son’s 1617 and exchanged it with my V2 or VC. If you go to my uploads and look a few pages back there is a picture of me holding them end to end. They are identical. I just bought a pair of cheap Chinese made ones off eBay because one is a 12mm which I have a few bits for. They were either 10 or $12 for the pair.

 

[Cherryville Chuck]

With a spiral you should be able to remove the nut over the bit. Then you can tap on the side of the collet and keep rotating it as you do and it will eventually release (as in 3-10 minutes). My M12V wasn’t available in 1/4” and came with a reducer which I’ve never had an issue with. If you purchased a Musclechuck for that router it would also need a reducer as the MC also only comes as a 1/2”. You can’t get a bit stuck in one which is why I switched my M12V2 to it to use in my table.

 

[Cherryville Chuck]

That’s odd. That lip is supposed to lock into a recess at the top end of the nut. In use you loosen the collet and spin it a turn or two at which point it will get tight again and need another turn with the wrench. When it loosens again it has pulled the collet free of the taper.

 

[Cherryville Chuck]

That's good to know. I've seen before which company made the routers that start with 320 but I can't remember who that was. It wasn't Ryobi. I've never seen a Ryobi one using the Bosch style collet. That's lucky for you because that collet will likely be around for a long time something that hasn't proven to be true with the Ryobi made routers.