I use this same machine

This is a great machine. I do not use the flap part. Have read many comments about how difficult it is, and some even say dangerous. So, I use the small bladder on one side, with 80 grit and the large one with 150 grit. I mainly use it to clean up rounded over (with router) corners to build outdoor furniture. I use a handheld bicycle pump and it is probably less than 10 psi because I think I push too hard and it would be too aggressive at a higher psi. When I was first looking for one, there were only two choices that I found … the Grizzly for about $275 or another one for around $1,000. No agonizing here. It’s basically only a benchtop grinder set up with different shafts to hold the sanding component. Have use the Grizzly for about 2 yrs. now with only one problem … my bladder split. Could probably be patched just like an inner tube and I may do that. However, Grizzly promptly sent me a replacement with no hassle. I have used different spindle sanders, and drill press accessories, but this dedicated machine is really great. Dust collection is an issue, but I use a Big Gulp spring-clamped to the table and it does a pretty good job.

OK. I was just trying to add a comment to a prior review but it required a picture. So, I picked a picture that really has nothing to do with this comment. But, there it is!