RATTMMOTOR 80mm CNC Spindle Motor Clamp Mount Bracket Support Cast Aluminium with 3pcs Screws for φ80mm 1.5KW 2.2KW CNC Router Engraver Milling Water Cooled Air Cooled Spindle Motor

There is no holes. You have to drill the holes yourself in the right places. HUH!

This thing is fine. It's kind of a crummy surface finish because it was sand cast, but it fits a 65mm spindle fine (I'm using a Makita trim router in there). One of the bolt holds isn't threaded, but who cares? 2 bolts gets the job done just as well. It's beefy as hell, plenty of space to put threaded holes for mounting.

Bad surface quality, one of the mount holes is not tapped at all. Bolts quality is below average

Works great. My only complaint is that the size doesn’t allow for mounting directly to aluminum profiles with 40mm t slot spacing. I had to machine an adapter plate, but I used the opportunity to make the adapter plate able to tram the mount using an eccentric bushing. Seems to really hold the spindle tightly.

I picked this up to add a water cooled spindle to my Taig CNC mill, all of my pictures are after I did some work on it. I'm in a good situation because I already have the mill up and running and could clean it up before swithcing over. If you're not up and running yet, buy two and use one to get started and clean up another, then sell the first one used. As recieved, its not too bad. The enitre part has been sandblased, but if you look closely you can see that the back face was hit with a flycutter to flatten it, and the bore for the spindle has been machined too. To get started on cleaning it up, I clamped it on the back face and machined about 0.020" off the two side ears where the bolts will go. I'm glad I did this because from top to bottom the thickness was different by about 0.010" to 0.015". With that done, I flipped it, fixtured it onto 1-2-3 blocks and moved on to the face that it will use to mount to the mill. Since this surface came machined, it was relatively flat. On the first 0.010" pass some wavyness could be seen, there were some areas where all the cut marks from the flycutter were gone after milling, and some where you could still see them. The second 0.010" pass got it nice and flat. Then I took 0.020" off the top and bottom just to make it look good. I thought about it, but ended up not machining the bore, I don't think my tooling is stiff or accurate enough to make it better than it already is, and I measure the thickness of the bore to the rear face and it looks very even top to bottom. To attach it to my mill, I made an adapter plate out of 4140 alloy steel. I used my mill to drill locators where all the holes will be, using a 0.125" drill at the lowest pulley speed and went nice and slow, about 1IMP. Then I took it to the drill press and drilled all the holes thru to size, using plenty of Boelube. The adapter plate mates to the mill using 10-32 screws on a 1" pattern, and I pocketed out the back of the spindle bracket for the heads of the screws. The spindle bracket will attach to the adapter with six 1/4-20 screws, which is overkill but at least won't be the weak point in the system. On the back of the 1/4-20 screws, I used square nuts because it just fits to my mill and the square shape means I don't need to put a wrench on them. It took a bit of work to clean it up, but overall I'm happy with how it eneded up and would recommend this!