Sanding Belts Failing

[Mark Hockenberg]

I pulled out my old Porter Cable 3x21 to level a glue-up. I had three belts snap at the joint. I assume it's a glue joint when they're made. They are pretty old - Did these just fail due to age?

[Matt Day]

Likely just brittle from being old.

[Carroll Courtney]

They do and I bet it happens to most that has shops that’s not climate controlled.But I bet little gorilla glue will fix

[Mark Hockenberg]

Who makes the best belts now-a-days?

[Ron Selzer]

Yup, too old as in over a year old.
Buy all my small belts from Klingspor they all will break once they hit the one year mark, more/less. Wide belts from 2sand
Have better luck keeping them IF I use them when I first receive them and get them hot, then change for another until all new ones have gotten hot
Have blown all the belts at the seam, that I received with the used wide belt sander I bought.
When a new wide belt arrives here it gets used and hot right away then set aside until needed.
I imagine a pro shop or heavy hobby shop uses belts fast enough not to have a problem
Ron

[Frank Pratt]

This subject pops up fairly regularly. I have yet to have a belt break at the joint, and I have used some that are probably 15 years old (good sale). My current stock of belts (Klingspor) is at least 4 years old & I've had no issues with them. They are stored in my shop, which varies from about 5* C - as high as 30*C with fairly low humidity. Maybe high humidity is the issue?

[Mark Hockenberg]

My guess is these belts are 30 year old, stored in low humidity. Maybe it's time to part with a few bucks.

[Lee Schierer]

I had a problem recently with belt's breaking on my Porter Cable 3 inch belt sander. I was using belts that were over a year old with taped splices. I broke two in a row almost instantly upon starting to sand and was putting on the third when I examined the belt tensioner. I noted that it had an exposed stop and there was a place where I could place a shim that would reduce the tension an amount depending on the thickness of the shim. By experimenting I determined that a .045 shim reduced the tension enough that the belts didn't break but were still were tight enough so they weren't slipping.

[Ron Selzer]

My shop is in the basement, heated and cooled year round. No humidity problem in summer, might get low in winter.
Klingspor belts 3 times over last 5 years until I started conditioning them as soon as I got them.
3x24 belts, 40 and 120 grit
Like their belts and definitely like the price.
Just no luck with the splice holding up.
Ron

[Robert D Evans]

Geeze Mark, you're as bad as I am about saving stuff. I'm still hanging onto the power cord and switch from a bench grinder that died on me 25 years ago. Some day I'll need them.

[Bruce Wrenn]

Coleman, over at Klingspor's Woodworking Shop, says splices have a life expectency of just over a year. At the factory, they keep splicing stock in the freezer.

[Warren Lake]

I have new 3M stroke sander belts some still new in boxes in an attic all seasons and more in a damp basement over 20 years old. Those belts work like they were just made.

There seems to be some reason they cant make a splice that lasts on the small belts. I have new 3M 3 x 21 and still in plastic They are old, say 20 years old. I think ive had some blow up that were not in plastic, havent used that sander lately. Ill put the question to one of my sandpaper companies why splices on my stroke belts last and dont break. I can put a used stroke belt on thats done its time then sat for 20 years and still use it as its fine for what im doing.

I think the stroke sander belts at one point became either direction. Thats good, do its time then for the odd thing you need put it on backwards and there is some sharp left.

Dont think the belt sander belts go either way, they had arrows last time I did a bulk purchase of different grit belts. One year on the Klingspor till self destruct seems low, clearly it is what they told you but why?

[Randall J Cox]

My shop is in the basement, heated and cooled year round. No humidity problem in summer, might get low in winter.
Klingspor belts 3 times over last 5 years until I started conditioning them as soon as I got them.
3x24 belts, 40 and 120 grit
Like their belts and definitely like the price.
Just no luck with the splice holding up.
Ron

What do you mean by conditioning them? What do you do to condition them? Randy

[Ron Selzer]

put new ones on when they arrive and sand just long enough to get the belt hot, then put the next one on, repeat until all have been conditioned
good luck
Ron

[Warren Lake]

hard getting answers now as people are taking holidays with stuff shut down got my salesman instead of the Tech but still will get a tech when back, some not answered but shelf life thing on 3M belts is five years.

I wouild not buy sandpaper on price alone. Some companies one I know of even put some coarser grit in so you have the perception their stuff works better than your own brand. Not sure if that still goes on but was that way with one a while back.