Off Topic Portion: The warning is for trolls like the one who replied once to the last metalworking post confused and finding the title hard to read. Hopefully when trolls realize its real metal working content they can move on to other topics they will find more enjoyable.
On Topic Portion: After Jim Wilkins comment about abrasive discs I stuck one of my little mandrels in a drill press and cranked up the RPM. The discs were part of a batch I bought from Benchmark Abrasives. Suface conditioning pads. Not knowing which would work best I bought a pack of two different ones. A "red" one and a "grey" one. For some reason I thought they were green on the website. The grey one felt way to coarse, so I tried the red on. Working under the head of the drill press is a little awkward, but it works ok. You are working blind except when working on the side of the disc, but its not to bad. It will deburr the part, and leaves a generally nicer finish than sand paper. After just three molds (6 parts) the disc was about toasted. Being a cheapskate I could get a little more work out of it, but that wasn't really my goal. My goal was faster, cleaner, and more efficient deburring. Given that it wore out so quickly it also left a lot debris on the parts. I'll rinse them all anyway before going back on the machines, but they do need to go back on the machines. The back side needs customer name and catch phrase engraved yet. Still there was a lot of red abrasive bits all over everything.
Randy and Jim both mentioned belt sanders. I prefer to call them belt grinders, because that's the way I use them. Recently I made some repairs on the little Harbor Freight 1x30 bench top belt grinder. Mostly I just adjusted it and tightened up a bolt that holds the tensions tracking assembly in place. I was not hopeful that it would run the surface conditioning belts any better (at all) than it did the first time I tried them, but I tried one anyway. I had gotten a couple each of two different ones. Also from Benchmark Abrasives. I selected the one that felt finer (grey/green this time) and left the red ones in the drawer. It was difficult to get on. I had to wrap my arm around the machine and pull it against my body to pull the tensioner far enough forward to get the belt on. After turning it by hand a couple times I plugged it in back and and turned it on. No pleasant surprises there at all. It still would not turn the belt. Just being a little obstinate I started spinning the large lower idler wheel by hand with a finger tip. A little help didn't get it going, but I noticed it would turn fraction of a rotation before stopping. I decided to manually spin it a little faster. When I pulled my finger to safety the belt grinder kept going and then it sped up. It wasn't as quick as normal, but within a second or two it was turning at what visually appeared to be its normal speed. I still was not hopeful, but I wanted to see what the conditioning belt would do. I don't think I really ever thought about the machine again as I deburred moderately complex edges on 7 more mold (14 more parts.) Straight edges were easy, but walking round edges for hinge bosses around on the belt and cleaning up inside and outside corners was pretty easy to control. Sure it looks like it was done by hand but it looks good. Those parts are not all covered with a large cloud of abrasive debris. There is some I am sure, but nothing like from the little disc. The belt looks used, but its not worn out. I am sure I could do atleast another dozen parts with it. More since I'm a cheap skate and I'll push it to the end. After the little belt grinder came up to speed I don't recall it seeming to bog down one time while I was using it.
I mentioned two companies previously in this post purely for reference. So people wouldn't find it odd if their Combat Abrasives or their Wen belt grinder performed differently than I described. I am not endorsing or putting down any of the companies named. Just describing how the products I used performed.