Belt sanders

[DKanger]

I've got two 1" belt sanders, a 21" Makita handheld and a 42" Jet. In the last month, my belts started breaking at the joint. I have both directional and bi_directional belts of varying ages and they all are breaking after just a minute or so. I don't know if they are supposed to have a shelf life.....there's no expiration date on them. I'm tired of getting blapped in the face.

They are resin bonded. I don't know if that means the grit or the joint. Has anyone experienced this and can you glue them back together. If so, what glue did you use?

 

[scott99]

HI, I have a 2 inch X 48 belt grinder I have run for 30 years or so. I have used both types of belts and find when the sit about for too long they break on my first pass. I do not know if the glue breaks down from humidity or just from age. I tend to hang the belts from a rack in the basement and only have had "USED" belts break down. The new belts seem store that way just fine. It might be that after use a belt gets hung still warm or even hot from running and absorbs moisture at the joint.

I have tried to "reglue" belts and have always ended up with a bit of a lump at the repair joint. They look fine but when you run them its bump, bump, bump and then snap.

scott99

 

[DakotaDocMartin]

I've got two 1" belt sanders, a 21" Makita handheld and a 42" Jet.

I have a 42" x 1" Jet sander and have been using the SAIT Closed Coat Aluminum Oxide 1-Inch x 42-Inch Grit Sanding Belts I get in 10 packs for $15.55 shipped from Amazon. They go and go and keep on going. I've never had one let loose and I use them mainly on metal. At $1.55 each... I wouldn't waste the time trying to glue one. You might want to give a few of those a try.

 

[Weldon47]

Yep....Ive had a few break on one of my BurKing belt grinders & let me tell you: At 3600 rpm a breaking belt will definitely cause a momentary loss of sphincter tone!

Welfon

 

[Beathard]

What are y'all using belt sanders for?

 

[Marrinan]

Anything we want! Knives, spurs, bits, all kinds of metal that needs welding. Of the 2 inch variety I have 3-42", 2-72", in one inch 2-30" I just got my new 72 by 2 Terry Wertz TW-90 vertical/horizontal with variable speed with surface grinder attachment. Fred

 

[Ron Spokovich]

Having experience with sales of belts from a 'converter', and speaking with the factory that makes the adhesive, your failures are from age of the belt and its adhesive. Also, in some cases, surface prep of the joint is to blame. The adhesive is two-part, highly flammable, and must be applied under heat and a lot of pressure to the belt and the filament joining material. Some fail, some don't. I have old belts, and the story is the same. The adhesive is, in some cases, or maybe always these days, waterproof. It has to be strong and flexible, and the completed joint has a varying shelf life. Klingspor, whom I've ordered from, makes up their belts on-the-spot. Find a supplier who sells a decent belt cheap, as chances are they maintain fresh stock. Resin bond refers to the bond of the abrasive to the belt. I have, again, old belts that work fine, and others that don't. Use the butt splice, as you can reverse them and they're fairly bump free. The lap splice belts are directional, and may come apart. There's no way around the problem except for not buying too many belts at one time, and buying the freshest belts you can.

 

[DKanger]

Thanks Ron,
That pretty much sums up my problems and also for the little tidbits of technical info. I've got 3", 4", and 6" sanders but I use the smaller ones the most. I try to keep 2 each of 3 different grits on hand for each one. I'm not big on grinding stones....the sanders will remove material with a lot less heat build-up.

 

[LVVP]

Thanks Ron for the info

 

[Eugene Carkoski]

maybe you have the tension set to high, I have never had one separate.

 

[Runingfool]

When I order belts, made to order, there is always an experation date. The adhesive holding the joint breaks down and causes them to break under load in a short time. Not sure if this is your problem, but try a new one and see if it is still happening.

 

[jsix321]

Same thing happened to me. I just got back into building handmade items and my belts seem to last about a minute each. Frustrating and will be ordering more.