Thread: Help with my Makita 4" Belt Sander issue please!

afraid as you get older the joints become weaker

Did you put the belts on in reverse? ie: the arrows should indicate clockwise rotation when viewed from the RHS of the sander

Originally Posted by nosnow

afraid as you get older the joints become weaker

Could I overcome that but adding a layer of the fiberglass filament tape?

Originally Posted by rwbuild

Did you put the belts on in reverse? ie: the arrows should indicate clockwise rotation when viewed from the RHS of the sander

Thank you Ray, but I did put them on in the correct direction so no "I D 10 T", this time... , Cheers Peter

Peter, have a close look at the innards of the sander, there may be a build up of dust causing the problem. A good blow out with compressed air will help. If you don't have a compressor, take it down to the local servo and give it a blast. Standing up wind might be useful!
Alan...

Originally Posted by Uncle Al

Peter, have a close look at the innards of the sander, there may be a build up of dust causing the problem. A good blow out with compressed air will help. If you don't have a compressor, take it down to the local servo and give it a blast. Standing up wind might be useful!
Alan...

Nothing obvious Alan, but I’ll give it a go, thank you. Cheers Peter

It will be the glue join. Up here in the tropics belts don't last very long before they fail, so I only buy new one's when I have a project coming up.
Rgds,
Crocy.

Peter
The glue joints dont stand the test of time especially this last couple of years high humidity. I would say the fact they all went at the joint is a belt problem. Tracking problem with the machine usually results in the side of the belt being chewed up. Someone else was asking not that long ago about resticking them but the general opinion was just get new belts.
Regards
John

Originally Posted by rwbuild

Did you put the belts on in reverse? ie: the arrows should indicate clockwise rotation when viewed from the RHS of the sander

I don't have much experience with belt sanders and timber but quite a lot with free belt machines as a metal polisher. The arrows on the belt material are to allow users to refit belts in alternate directions when swapping grits with belts, rather than indicating a required direction of rotation. As the belt is operating in one direction, the leading edge of the grains on the belt coating wear and loose some of their 'cut'. The belt can be installed with the arrow in the reverse direction for the next time the particular belt is used, giving a fresher 'cut' and increasing belt life. When both edges of the abrasive particles become partially worn, the belt is considered a 'soft' belt and used further along the finishing route.

The direction which the belt is facing when installed on the machine has no bearing on the tension applied across joint during operation, that is a function of the machine speed, torque and the load applied by the user pushing it onto the work. Drive and idler pulley/roller sizes and the backing of the belt also have involvement in the ability of the belt joints to withstand use, some backings and coatings simply lack the flexibility to manage tight radius bends at high speed, and impose significant stress on the joints when forced to do so, precipitating early joint failure. Beyond all of that, age and heat also affect most belt jointing systems to a degree, so belts that have been stored for some time will have significantly greater failure rates and shorter time before failure than fresh belts.

The problem as has been mentioned, is that the glue joint is failing from lack of use. Discard them and buy new belts. In the past I have tried re-gluing after extensive joint cleaning, with pva, contact adhesive and even CA. All this had very limited success.

Jim

Hi Crowie

Same thing happened to me. I inherited a dozen or so new unused belts from my father after he passed away. They had been sitting unused for more than 5 years after I acquired them, so may have been 10 years old. All of them promptly fell apart at the join as soon as the belt touched the timber surface. As they failed one after the other in quick succession I do remember thinking to myself ' b*gger me, they're all fark@ed'.

All was not lost though. I kept the belts and tear off small sections when needed for rough hand sanding. It's a lifetimes supply, they are really tough and take a fair while to wear out.

just my 2c worth
Twosheds

Pete, I would give the fibre glass filament tape a go. I have used it a few times with mixed results. You have nothing to lose. I cleaned the joint and back of the belt with thinners then joined the belt with the tape and applied a block either side of the belt and left a "g" cramp on over night. As I say I got mixed results