Short shelf life for sanding belts

[Faust M. Ruggiero]

I try to keep a small stock of 3 X 21 and 3 x 24 inch sanding belts. I buy 3M and Klingspor belts. Even stored in my climate controlled shop, if I let belts get more than a year or so old, the seam tape will come off one side within seconds of using the belt. At $2+ each, I'm getting a bit annoyed. What good is high performance abrasives coating if you don't get a chance to use it. Anyone have better luck?
faust

[johnny means]

Hmm, I rarely use my belt sander, so belts can hang around my shop for years and I have never seen this happen. In fact, I've never seen any belt fail at the tape. Is there any thing unique about there storage or your shop? Stored near thinners or heat? Have you stressed the seam before using the belt? Maybe its happening during use?

[Jim Rimmer]

I've had belts fail but i had them in an un-airconditiioned garage shop in Houston (hot & humid). I will be interested in what you find out since you are storing in a climate ontrolled area. Have you contacted Klingspor?

[Lex Boegen]

I try to keep a small stock of 3 X 21 and 3 x 24 inch sanding belts. I buy 3M and Klingspor belts. Even stored in my climate controlled shop, if I let belts get more than a year or so old, the seam tape will come off one side within seconds of using the belt. At $2+ each, I'm getting a bit annoyed. What good is high performance abrasives coating if you don't get a chance to use it. Anyone have better luck?
faust

Yep, the same thing happens to me too. I've had never-used belts that were stored for several years break at the seam the moment I used them. For that reason, I only buy belts when I need them and in as small a quantity as possible. FWIW, I live in Florida so it may be humidity-related.

[Jim Andrew]

My belts don't hold up here in Kansas either. And it's dry here. Mostly. Tape just isn't the best way to join the ends of a belt. 3m used to make a joint with a overlap and glued. Those things never broke at the joint. Taping is just the cheapest way to do it.

[Don Selke]

The same situation happened to me with sanding belts. I seldome use my belt sander since converting to ROS sanding both 5" & 6" sanders. Here in the desert SW where temperatures can be 115 and on ocassions higher in the summer, belts just do not last. The adhesive that they use deteriates in hot weather.

[Jay Allen]

In the shop where I work they don't sit on the shelf that long. They go through quite a few of them in the Laminate counter-top department, mostly the 4x24" though.
I do have several of the smaller 2.2x14" belts for my Porter Cable sander that are quite old though and no issues with them either.
We use Kingspor exclusively and I think the company buys them either bi-monthly or quarterly? We get sleeves for the spindle sander from them too.

[John McClanahan]

I think Klingspor is the one who recommends using sanding belts within a year or so of purchase, for this very reason.

John

[Karl Brogger]

There's good 3M stuff, and there's not so good 3M stuff.

I think I'm buying the 240D belts and the joint doesn't let go to often. Maybe 1 in 100? I do have some belts that sit around for a year also. I like to buy in bulk when I can.

Come to think of it, they seem to come in runs. I'll get a case, a few in it will break, then I won't have any fail for a long time.

[Steve Peterson]

Tape just isn't the best way to join the ends of a belt. 3m used to make a joint with a overlap and glued. Those things never broke at the joint. Taping is just the cheapest way to do it.

I just bought some 4x24 belts for my Ridgid belt sander that have overlapped joints. The bump is so thick when the seam comes around that it leaves ridges in the finish. I prefer taped seams. I am in dry California and have never had a glued seam fail.

Steve

[Gerry Grzadzinski]

I've had some 3M purple belts that lasted at least 5-8 years, and I had some cheaper belts that came apart. However, when they failed i was sanding phenolic plate very aggressively, and the belts were getting very hot before they failed.

[Bruce Wrenn]

Our WW Assoc. recently had Klingspor rep as featured speaker. He said Kelvar tape only had about 1 year of shelf life. At the factory, they keep it in a freezer till ready for use in making belts. We used to make belts for a 6 X 48 sander. Had a pattern to cut material, ground off abrasives in area of overlap, and glued with PVA glue. Only real problem was heat destroyed the PVA glue. Seems like we went to epoxy instead, but can't remember as it was about 40 years ago, and statute of limitations in this state is three years. Now, even though we have a Klingspor store here, I buy my belts from tool vendor at the flea market. For the 3 X 21 (Klingspor brand) he is a buck a piece. When he has some new stock, I buy a couple. Once on a tour of 3M's facility in High Point, I bought a CASE of purple belts at a steal. Of course after I only got to use a couple (due to joint failure) they weren't such a steal. Most expensive belt I have ever used. Still have a couple of boxes of them left

[James Boster]

I purchase belts from both Klingspor and Industrial Abrasives. Industrial Abrasives rep said I should not buy belts that I could not use in 18-24 months.

[Jerome Stanek]

I have some belts that I bought in 1992 and just started using them and they are fine. Stored in the sander case in an unheated unairconditioned shopin norther Ohio

[Callan Campbell]

+1 on all the posts about the noted short life of the seams for the belts. Although I too have never had a problem with storing belts and then using them years later, I am told over and over again by suppliers that I'm getting lucky since the agreed best life once the belt is made is under 2 years, with some only rated for 1 year. I don't know how I'm dodging the bullet on this with my very infrequent belt changes, but I've never had a belt blow out at the seam yet.:D:D:D
My belts are all stored in my basement shop, maybe the fairly constant low temps help, cause it sure isn't a stable dept for humidity down there!
Anyway, good luck with your issue.

[Jeff Duncan]

I've seen this topic come up before with the warnings of long term storage and I'm another one of the lucky ones who has not had the belt breakage problem. I do wonder if breakage also something to do with how one uses the sander? Excessive downward pressure for instance generates a lot of heat.
I don't use my belt sander all that often, I know some of the belts are about a decade old now, and last time I used them about a month or so ago they held up fine. Could be just luck though.
good luck,
JeffD

[Jim Rimmer]

Our WW Assoc. recently had Klingspor rep as featured speaker. He said Kelvar tape only had about 1 year of shelf life. At the factory, they keep it in a freezer till ready for use in making belts.

Maybe we should keep our belts in the freezer. I'm sure LOML would like that. :D

[Bruce Wrenn]

The Kelver splices were developed to allow belts to be bi-directional, and not have a bump where the lap was. I just used the last of of my old lapped belts a couple years back. I got them from Noah's clearance sale upon the completion of the Ark' They really weren't that old, but they were old.

[hank dekeyser]

Interesting subject - I have a few belts that are well over 5 years old and NEVER had a single blow out. I buy everyrhing from 3M purple, harbor freight, you name it. I buy belts that are either discontinued, on closeout, on sale , whatever. I have yet to spend more than $2 on a belt and never had one fail. I store my belts in a drawer with a bunch of other sanding related crap (big drawer) and my shop is hot and humid in the summer and sometimes frozen solid in the winter. I don't get it- never heard of anything like this.

I'm going out to knock on some wood now - seems I'm long overdue to have a belt blow up in my face

[glenn bradley]

I don't really think of a year as a short shelf life. Even so, like johnny, I rarely use the belt sande and so have belts that are years old but do not fail when used. I do, however, only use them for a short period. Perhaps if I was really using them they would heat up and fail too.

[Michael A. Tyree]

This thread corresponds with one I started today, r.e. belt breakage problems with taped seam belts. I've worked out of the same shop since early 1980's and never had problems until the taped belts came out. I also never had issues with lapped belts that caused surface problems. I'll avoid many comments here to allow those interested in this subject to read the other thread.
I buy discs in 50/100 rolls or packs and as a non commercial user I still need the savings on bulk buys. To buy belts in very small quantities is just a waste of money & shipping costs. Unless I change my mind after some phone calls Monday, I'm buying lapped belts!

[Jim Andrew]

Michael, where do you find lapped belts? I don't use my belt sander often, but had a 5 pack, they lasted about 3 minutes when I tried them. Bought some new ones at Harbor freight, they were a little better, and I picked up their last pack the other day, and none broke at the seam, so they were fresh.

[Michael A. Tyree]

I actually don't know , at this point. I have a few leftover belt from Sungold, made in Korea and they are lap joints. The Sungold abrasive is typical AO but belts are capable of total wearout before you toss them. I'm calling them this a.m., location is in NY. They might have made the switch too? I've had this Bosch sander as long as they've been around and never had belt issues until taped joints and the 1st ones I bought were fresh and breaking. I considered the machine, as a possible culprit but springs hardly have a chance of getting stronger. It tracks well and runs like it did when new. The platen pad is a replacement with new cork underneath too. Seems like I saw a "slicker" platen once in a catalog? There is a lot of heat generated at the belt friction point as the sanders are heavy tools. My theory is the belts break as soon as a temperature is reached that releases the belt joint adhesive. This thought comes from fact that the sander when cold will run ones of these belts longer the first time around. Not very long, mind you! It may also be a failure from simple belt tension?

[Wade Lippman]

For what its worth.... I bought a bunch of Woodstock belts when I bought a sander 3 years ago. Never had one fail; I even ran one backwards to equalize the usage.