View Full Version : Belt Repair Idea

04-21-2015, 12:35 PM
I got this from my friend/knifemaker, Bill Keeton. Who, among us, hasn't had a belt come apart? Thanks, Bill!

"Hi Steve!
I thought I would go ahead and send this to you before I forget it.

I will send you a picture or description later of the type of Gorilla glue I've used in the past.

I sincerely hope this helps you.

For God so loved the world that he gave his one and only Son, that whoever believes in him shall not perish but have eternal life. John 3:16"

Sharp people visit

How to repair 3M 220 grit silicon carbide polishing belts

? Peel off old splicing tape and save it.
? Sand off belt area (on both sides) where the glue and splice was on.
? Rough up this area with sand paper.
? Lightly sand tape to remove the old adhesive or turn it over and use the reverse side.
? Wet both sides of the belt with a damp towel.
? Apply a small amount of Gorilla glue and align the belt very carefully.
? Put it in a delrin 90 degree fixture and clamp another piece of delrin on top of it.
? Let it cure properly and this should repair the belt.
? If you can?t salvage the original splice, try soaking carpet tape in something that will remove the adhesive. Let it air dry and then use it instead.

Doug Lester
04-21-2015, 10:14 PM
It seems a lot of trouble to go to to fix a consumable item like a grinding belt. I'd just put on a new one.


04-21-2015, 10:28 PM
I wish there was a way to re-grit them ..... like brush them with epoxy then bury them in the sand box or something. I'm only half joking when I say that. :) Has anyone ever tried something like that with any success?

04-21-2015, 11:19 PM
Ever have a belt fly apart? It can be fairly dangerous. I won't trust a belt that has a flaw that might make it come apart. Think I'll pass on repairs.

Likewise, if you've ever tried a cheap belt and had that thump-thump-thump as the high spot rolls by then using a repaired belt that's slightly off is not very useful either.

I did some consulting work for a company that makes sandpaper. Adhesive (epoxy) is applied to the paper, and then it is electrostatically charged and grit (it's not sand) which is oppositely charged is applied. The excess is vacuumed or blown off. Next, a new layer of adhesive is applied. If you picture the grit as being a tiny ball, there is adhesive attaching it to the paper and then surrounding it up to about 75% of it's height. Only the tip of the grit comes in contact with whatever you are sanding. The long belts of sandpaper are then fed through a long, long oven where the adhesive cures. So re-surfacing a belt would be a tough proposition.

Heat is the enemy of sanding belts. Once the adhesive gets soft, the grit pops off. Long belts allow the surface to cool a bit between contacts with the sanded surface.

04-22-2015, 10:55 AM
Not a bad idea for a $5-8.00 belt, IMO. To each his own.
I've glued and taped belts back together, with mixed success.
Make sure you start them out slow and let them run full speed
for a while to see how they are going to hold up. Apply pressure
and speed in increments. Of course be careful and if it's not for
you, sure, don't try it. May be more applicable to a situation where
you NEWED that belt and need it now, don't have more, or time to
wait for re-supply. Use wisdom.

04-24-2015, 12:47 PM
One of the machine shops in my area used to make their own belts. I've thought about it many times. Even with quality belts, it seems like I buy a lot of belts.
What these guys did was buy emory cloth, cut it to the length needed, then soak the ends to get the grit off. Glue them up and start grinding.
Just a thought.

04-25-2015, 04:41 PM
Sounds interesting.