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Seems like the DW660 is still being used a lot – it’s just – for most people you do NOT want to try to replace that bearing. They made it a lot harder than it is on most tools – and then seemed to put the cheapest ‘Made in China’ bearing they could find in there. So it seems right now the best thing you can do (and it’s what some Shapeoko people do) is just keep a spare around. It really pains me to have to pay $66 with tax for a whole unit when I know it’s a $1 bearing if you buy 10 from China direct (or $5 if you buy just 1 from Amazon with Prime shipping) but it seems it is very hard to get that bearing out on this particular tool. First, there’s this snap ring – I thought it was holding the bottom block to the shaft so I went to remove it- the one that holds the tool free changer on is easy to remove, but the snap ring on the bottom block is so hard it will easily break any cheap snap ring pliers, and it even seriously ate away at some big steel flat head screwdrivers I ended up using instead. Then, I got it off, got out a bearing puller – pulled that bottom block off with relative ease. Problem is – now you have this bottom block, with the bearing in the middle of it. That’s where I got stopped. Nothing would even begin to move that bearing out of there. The bottom block isn’t flat on either side, and any way you come at it when you start applying pressure to get that bearing out of there you just end up bending something on the bottom block (which is weaker than the force holding the bearing in).

I see no way of getting that bearing out of there without destroying the block in some way. I’ve searched and searched and I’ve yet to find a single person describe how they did it anywhere (just a whole lot of people saying ‘I’ll replace the bearing’ only to either never hear from them again on the subject, or a post from them saying ‘Umm, I’ve changed my mind, I’m just going to buy a new one.” Now I know why.) If you have a Type 3 like me (Dewalt keeps the same model number, but drastically changes the design – the first bearing I ordered cost $15 and turned out to be the wrong one because I didn’t think to check for a type number before ordering) the bearing is a R8-2RS bearing.

Personally I want to try one of those Chinese spindles – but I’m not 100% sure how to wire a VFD. It sure would be nice to have software speed control though – should extend tool life.