I bought this 5" 4-jaw plain back chuck because it was the right size for my 6" rotary table. Its a Gator & seems pretty decent for the cost. Here is how I machined an adapter plate to marry the two. I decided to turn a close fitting male boss protrusion that fits the chuck recess as opposed to flat surface relying on bolts & friction to stay put. I'm not convinced its 100% necessary because right now that's how the plate attaches to RT platen anyway but figured it cant hurt either. If I do experience any plate movement I have one more trick - an MT stub located in the RT bore with a machined disc that fits the center hole of the plate.
Ideally I would have preferred cast iron or steel for durability but I had this 5/8" cast aluminum tooling plate stock so figured I'd give it a go. I'll just have to have to be careful not to ding it up, but accuracy wise it turned out decent. I was a little apprehensive about turning the rough stock with those standoff donuts sandwiched between the faceplate (another reason I was kind of chicken of iron). It went clunkety-clunk until stock became round but nothing moved or flew off. Now I'm more confident CI or steel could be done the same way as long as the cuts & speed was moderate.
Ideally I would have preferred cast iron or steel for durability but I had this 5/8" cast aluminum tooling plate stock so figured I'd give it a go. I'll just have to have to be careful not to ding it up, but accuracy wise it turned out decent. I was a little apprehensive about turning the rough stock with those standoff donuts sandwiched between the faceplate (another reason I was kind of chicken of iron). It went clunkety-clunk until stock became round but nothing moved or flew off. Now I'm more confident CI or steel could be done the same way as long as the cuts & speed was moderate.