Finger sanding belts breaking

[Lazurus]

I have an old style B&D finger samder which I inherited. Last night I was using it to shape some wooden bannanas and every few seconds the belt broke. Anyone any idea why, they were fitted in the correct direction, very light pressure and each one went at the seam. Bad batch, platen problem? any idea?

 

[MikeG.]

They don't last long, I'm afraid, but they shouldn't go that readily. I suspect you have a sub-standard batch of belts, or they are really old and have just deteriorated.

 

[Robbo3]

I seem to recall this being discussed before. Something rings a bell about the common belt length being 5 or 10 mm too long thus the belt couldn't be tensioned properly.

 

[AES]

I think Robbo 3 is right (but also can't find the post now).

I too have the B&D "Powerfile" (it's probably newer than yours) which I bought from Axi, together with a set of belts of various grits. I've found those OKn (but as someone else suggested they don't last too long!) PROVIDED you make sure the belt is tensioned correctly. (BTW, I found some cheapo belts somewhere but they lasted all of 30 seconds each. They're now kept for hand work only).

 

[loftyhermes]

I have one of these and started cutting up belt sander belts which happen to be the right length, (457mm IIRC) into ½ strips with the aid of a little jig. Never had one break yet.

 

[AES]

Hullo Lofty. I for one would be interested in your little jig, AND the method, the glue, etc you use to make your own belts (for the "Powerfile", and for my "big" belt sander - 1100 mm wide).

I "know" one has to cut a "scarf angle" for the joint, and that it needs to be cut so that the cut angle leads in the direction of belt rotation. (AND that the belt length needs to be pretty accurate too)!

BUT no matter what sort of cloth or tape I use to reinforce the joint, and no matter what glue I use, my DIY belts always seem to last but a few "millisecs" in use - broken long before the grit is worn out.

So any tips and info you can give on DIY abrasive belts would be most welcome at least by me (and possibly other members too)?

TIA

 

[loftyhermes]

Hi AES, my jig is just a piece of wood turned round and a 12mm shoulder turned on it then a Stanley knife blade fixed to the end and the belt just pulled round to cut the strips off. My belt sander takes 75mm x 457mm belts so I can cut 6 power file belts out of one belt, nothing else to do them.

 

[Lazurus]

Hmmmm doing a bit of research the B&D powerfile belts are 451 x 12mm, think the belts I got are the 457 length, that may be the issue.

 

[AES]

Thanks for that Lofty. How do you join the 2 ends together? (or don't you? i.e. are the already belts of the right length, and you "just" strip them to the correct width)?

 

[loftyhermes]

AES, yes I just cut the belt into strips, the belt length is just right for my power file.

 

[loftyhermes]

Hmmmm doing a bit of research the B&D powerfile belts are 451 x 12mm, think the belts I got are the 457 length, that may be the issue.

I cut my belts from 457mm belts and they work fine on my file.

 

[AES]

OK, all clear, thanks Lofty. (Neat little jig BTW).