Sander Belt Joint Failure

[edward woods]

3" sander belts (couple of brands) stored in my unairconditioned garage-shop are coming apart at the seam as soon as they are applied to the wood. Does the glue fail over time or with moisture? Has anybody else had this problem? Ideas for rescuing them?

[Bill White]

Some folks have repaired, but I just get a new belt. Consensus is that belts will be prone to failure after about a year. I buy just a few at a time. Never had one break (yet).

[Dave Cav]

This comes up periodically. Yes, the glue joints age and fail. When I took over a school shop program a number of years ago one thing I inherited was around a hundred belts for the portable sanders. Every one of them failed, and trying to repair them wasn't worth the effort. I threw them all out.

[Dick Mahany]

Very common for old belts. I lost 3 boxes of 3x24 belts that I bought on a bulk sale and had them stored in my garage for several years. The belts failed almost instantly on contact with wood. I threw them out after cutting up a few for general purpose sanding on my lathe.

[glenn bradley]

There are some things that it does little good to stock up on no matter how good the sale is. Glue, filler. abrasive belts, many finishes, etc. The general consensus from those who attempt repairs seems to be to use the failed belts as sandpaper and buy belts as you need them.

[Kyle Iwamoto]

Yes, they get old and fail. Coincidentally, I just had to toss out a bunch of 6 x 48 belts that I did a bulk buy.... I lost 4 belts in 1 afternoon. Tossed the "good" ones too out since they were all bought at the same time. Lesson learned, 1) using those magic sanding belt "erasers" makes the belts last for long long time. 2) don't buy too many belts, since the glue doesn't last forever.
I'm about to lose my drum sander conveyor belt soon. That one is not cheap. That is a tool I will have a hard time not having...... Maybe I should order a new belt.
Anyone tried to apply CA before they fail to strengthen the joint?

[Ron Selzer]

Have lost lots of belts that were brand new never used just one year old or older. Give them to High school wood shop where I work. Kid cut them up and use them as regular sandpaper.
One thing that seems to help is when I first get a belt is to use it just long enough to get it hot, then set it aside and heat up the nest one. Have not tried a heat gun yet. I just sand with them
Ron

[Bill Space]

Have lost lots of belts that were brand new never used just one year old or older. Give them to High school wood shop where I work. Kid cut them up and use them as regular sandpaper.
One thing that seems to help is when I first get a belt is to use it just long enough to get it hot, then set it aside and heat up the nest one. Have not tried a heat gun yet. I just sand with them
Ron

This ^^^

Reading the above posts amazed me that you guys would not have repurposed the failed new belts!

[Lee Schierer]

My Porter Cable 3 x 21 belt sander applies a great deal of pressure to the belts. I was getting belt failures and really needed to use the sander. I found that I could place a 1/16th inch thick spacer in the tensioner and it would back off the pressure enough so that belts wouldn't break. I sanded the entire piece without breaking a single additional belt.

[Osvaldo Cristo]

3" sander belts (couple of brands) stored in my unairconditioned garage-shop are coming apart at the seam as soon as they are applied to the wood. Does the glue fail over time or with moisture? Has anybody else had this problem? Ideas for rescuing them?

I had a batch of 20 years old belts from B&D I tried to use some years ago: every one barely resisted the handling without glue fail. The ones that resisted that handling, literally, broken apart in a couple of seconds even without any load.

I do not know the kind of glue used in that application but I read in some places it is "programmed" to fail in a couple of years. Since then I do not purchase bulk sand belts - just on demand.

[Frank Pratt]

This subject comes us periodically & I'm really curious as to what the deal is. Lots of people report the problem, so it is a real thing. I've never had a belt fail at the glue joint and some have been 15 years old. My current stock of belts (Klingspor) is about 10 years old & I haven't had a failure yet. I got a bunch of them on a good sale.

They are stored in my garage/shop, which is heated when I'm in there & otherwise the thermostat is set to 4.5* C. No AC, but in Alberta it doesn't get terribly hot. average humidity is typically around 50 - 60%

For those with failures; what are your storage conditions.

[Bruce Wrenn]

Coleman from Klingspor gave a talk to local WW group a few years back. Said Kelvar splices have a lifetime of about one year. At factory, they keep splicing material in a freezer to extend it's life. Old fashion, single direction belts lasted, longer, but had a "bump" at the joint. Best to buy only what you need, and from a seller with high inventory turn over.

[Frank Pratt]

Coleman from Klingspor gave a talk to local WW group a few years back. Said Kelvar splices have a lifetime of about one year. At factory, they keep splicing material in a freezer to extend it's life. Old fashion, single direction belts lasted, longer, but had a "bump" at the joint. Best to buy only what you need, and from a seller with high inventory turn over.

Then why are my belts lasting so long then? My storage conditions are not exactly ideal.

[johnny means]

I've always thought the diagonal seams were a big part of the problem. Think about how one peels a sticker or piece of tape. You try and get a corner started, then the rest comes easily. If the seams were straight across, they'd have to fail all at once.

[Mel Fulks]

Thanks,Bruce, had not heard that. Does Klingspor sell both types? Can't say that I ever noticed a bump with any.

[Bill Dufour]

Climate. When I lived in the San Francisco bay area stuff lasted much longer inside or outside then it does here. We run 20-30 degrees hotter in summer and 10-20 degrees cooler in winter. Storing anything on a shelf when it is 90 degrees inside is very different then when it is a constant 58- 68.
I think the lives in the desert and his belt storage shelf sits at over 100 degrees for 1/2 the year. In winter he probably lets them freeze. I always heard freezing was bad for glue. Wood glue fails at low temperature something like 150 degrees. Probably easy to reach in the trunk of a car driving home from the sanding belt store or in the USPS truck.
Bill D

[Warren Lake]

Klingpor one year, 3M three years

Like all of life there is some nonsense involved. I have 3M stroke sander belts over 20 years old in an attic that goes from insanely hot to cold in the winter and non of them blow up.


Ill give as far as a 3 x 21 for my Rockwell sander will get very hot compared to the 6" x 309" stroke sander belts. My stroke sander belts do not blow up, so clearly 20 years ago people could make belts with an insane shelf life.

[johnny means]

Klingpor one year, 3M three years

Like all of life there is some nonsense involved. I have 3M stroke sander belts over 20 years old in an attic that goes from insanely hot to cold in the winter and non of them blow up.


Ill give as far as a 3 x 21 for my Rockwell sander will get very hot compared to the 6" x 309" stroke sander belts. My stroke sander belts do not blow up, so clearly 20 years ago people could make belts with an insane shelf life.

I assume that the reason why handheld belt sanders are a problem is the smaller radii that the belts are being flexed around. Also, the shorter lengths translate into more heat.

[Warren Lake]

sometimes the new green stuff.

Green environmental glue and since I was doing production stuff knew that stuff had gone backwards and worn out well before the past stuff.

that was hand sanding paper that was failing early on me sorry a bit different but still a reason that things went backwards at one point

[Dave Cav]

It's interesting that this doesn't seem to apply to widebelt sander belts. I have several belts that are five, six, seven years old that I run with no problems. I have never had a joint failure on a widebelt sanding belt. I wonder why they can't do the same thing on portable belt sanding belts that they do on widebelts, what ever it is, to make them last.

[Bruce Wrenn]

It's interesting that this doesn't seem to apply to widebelt sander belts. I have several belts that are five, six, seven years old that I run with no problems. I have never had a joint failure on a widebelt sanding belt. I wonder why they can't do the same thing on portable belt sanding belts that they do on widebelts, what ever it is, to make them last.


Are your wide belt sander belts bi directional, or single direction only? The reason the splice is diagonal is it's not all on the roller at one instant.

[Dave Cav]

Are your wide belt sander belts bi directional, or single direction only? The reason the splice is diagonal is it's not all on the roller at one instant.

I have both. No failures (yet) with either.