Tom Militano
KNIFE MAKER
That black crud is all over my platen and my wheels too.
I am going to call the folks at K & G supply this week, I hate being the bearer of bad news!:sad:
The more fuss they hear at St Gobain/Norton the better!
No, Lawrence, these are blue belts. I got a couple of the brick red belts in 120 grit to try out. I should be finishing the 60 grit grind on a knife that I have on the bench and should be giving them a tryout.
Doug
I've been having the same problem. I wasn't aware what was causing it. It got bad enough that if I did a lot of heavy grinding, then shut the machine down while I ate lunch, that the belt would stick to the platen and my drive wheel. I'd have to turn it by hand to break it loose so the grinder could run again.
I have a short piece of planer knife that I cleaned the drive wheel with, and clean the platen whenever I change belts. Going from a 120 Blaze to a more flexible belt without cleaning the platen leaves "worms" in my blade.
Gene
Those Blue Belts are Silicon Carbide and work great for handles, I still prefer Ceramic belts for 36G 50G - 120G work on steel.
The blue belts I have from Norton are from their Norzon line. The abrasive on these belts is Alumina-Zirconia (or also commonly called zirconia alumina).
Hence the common term of "Zirc belts".
It will significantly outperform both aluminum oxide and silicon carbide, but it is not as friable, so it's best suited for metal only.
Before the advent of the various ceramics, the Zirc belts were king for heavy grinding applications.
Norton has changed the backing compound recently to increase the life of the product and reduce grain loss. When the belts are hammered asymmetrically (ie; handheld), this problem shows up. They are working on a solution but you can appreciate it will take time, testing and approval. The engineers would really like to get their hands on some of these belts that have exhibited problems in use. If anyone that I have sold belts to has examples, please send them to me. St Gobain will replace the failed belts and send them to quality control to get this worked out.
We haven't found anything that will outcut BLAZE (and we've sampled a lot). Let's help them solve this backing problem.
This is from our rep in Canada. Can't speak for others, but I can speak my respect for this company!
Rob!
Hey Laurence
I'd like to send you a belt to test out for me. I'm pretty impressed so far, but I don't work them as hard as you do. Would you mind? Just PM or email me your address if you're game.
Rob!
No, Lawrence, these are blue belts. I got a couple of the brick red belts in 120 grit to try out. I should be finishing the 60 grit grind on a knife that I have on the bench and should be giving them a tryout.
Doug
Laurence, did you try different speeds with the Norzons? I have no experience with them, just wondering if maybe that would change their performance. Or maybe different pressures.
i too had the last 2 batches load my platten with uneven black crap (is there a way to clean the back of the belt to get the goo off before i use them