Belt Sander Friction Drive

[powdersummit]

I know the idea has came up in passing on this forum and a couple of other forums. The idea seems sound, you get a large contact area with a rough surface that will minimize slip. There is a thread on endless-sphere that goes into the idea specifically. It isn't very in depth and they are talking about electric but here it is.

http://endless-sphere.com/forums/viewtopic.php?f=28&t=24057

The idea of using a double sided timing belt for the drive has came up a couple of times but the cost on those belts is kinda high for cheap skates such as ourselves. I looked into coating a flat wide rubber belt with a urethane coating but it was still going to cost too much for a disposable part. If we assume that our drive spindle/drive belt is dispensable what would be wrong with using a belt sander belt. If a person was to use a 3x18 or a 3x21 at less than 4 bucks a piece (less if you bought in bulk) you wouldn't be crying over a 30 dollar belt if the if it shredded or wore out on you, just slap a new belt on and be on your way. You could even coat the belt with a urethane coating for better grip on tires and extended life.

I'm working with my Cad program trying to figure out what is going to work in theory. Right now I'm looking into belt sander design, belt tracking, and getting the greatest amount of hard contact area for the best grip. I am also looking at reducing the drag of the belt for better efficiency. Anyone who as turned a belt sander by hand knows how much drag is there. I think most of it is due to the raised flat surface that is used for the actual sanding on flat material and the amount of friction that creates. I am basing most of my work thus far on using a 3x21 belt due to cost and availability. 3 inch wide seems ideal for contact area on the drive roller and keeping the tire from flinging junk into the belt sander assembly. If anyone has any insights on the idea I'd love to hear them.

Carl

 

[loquin]

I've never seen a belt sander belt that allowed for wet sanding... so, unfortunately, the adhesive probably wouldn't hold when the belt gets wet... And, you would have to use the cloth-backed belts, not the inexpensive paper ones.

But, if you used a canvas-type belt, you should have plenty of area to hold, even without a grit, or if wet. Really, a rubber belt should give you plenty of area to not slip, even if wet...

Maybe we should be looking at narrow conveyor belting.

 

[powdersummit]

McMaster.com has wet/dry sanding belts in a 3x24 size that has a polyester cloth backing. Just do a search at mcmaster.com for "abrasive belts" there is a section for waterproof aluminum oxide sanding belts. I had looked into the conveyor belts but the problem is diy joining them. There is a fair amount of force involved with a friction drive. I'm afraid the speed of the belt and the small diameter of the roller would cause the diy joint to destroy itself. I have been having problems finding a good selection of shorter wide flat belts and like I said I don't like the idea of having to join belts. I appreciate your input Loquin, someone here has got to keep us honest. If you find any other suitable cheap belts point me in the right direction. I would love an off the shelf solution.

I'll keep working on the idea. I've been playing with the numbers on speed so once I have a better idea on drive size I should be able to get something drawn up.

Carl

Carl