One day after having not sanded with my delta 1x42" belt sander for a long time I noticed that all of my sanding belts were breaking at the seams. After reading all over the internet and here I discovered that the adhesive used apparently doesn't last forever and they use some sort of special industrial process. So I figured I was out of luck and would have to throw away a dozen unused belts.
Well I think I found a solution!
In my first attempt I used the same tape that was on the belts and reaffixed it to the belt with contact cement. Did the basic instructions on contact cement and reattached the tape to the belts. I think I used a solvent to clean it first. I haven't tested it extensively but I did put it on the machine and used it to sand with no problems. Probably ran it for a good half hour.
Since it is hard to get that adhesive tape off in one clean piece I went searching for other possible products. I was going to try muslin because it is very strong and should hold onto the contact cement well but instead my mom suggested some sort of poly ribbon. Not the type you wrap presents with but some sort of woven one that you would trim certain sewed materials with. She had 1" wide type and when I gave a good tug on it the stuff was stronger than I could imagine. I was unable to break it pulling with both hands. So I went to work and did about 6 belts. I cut a strip of the material, did the contact cement thing, then clamped it together for a little while. I haven't tried these belts yet so I will have to report back on these results. My one fear is that any of the alternative materials might fail from rubbing. They are all very flexible so that should not be a problem.
I also have no idea how well this will work on a belt that is very wide like 4-8" but I think it may work as long as the material is applied evenly.
Hopefully there is new life in our belts yet!