which type of grit?

[Jim Wilson111]

Which type of grit would last longer in a 6oo grit, alum. oxide or silicone carbide?
Thank You for your replies.
Jim

[ranger1]

I would say silicone carbide.I personally like the zerconia.

[NuViking]

Silica carbide does last longer. But using them wet makes both lst longer.

[Jim Wilson111]

Is zerconia made in 600 grit?

[Ray Rogers]

Maybe a better question here would be 'why do you think how long it lasts is important'?

A lot depends on what you are sanding, Silicon carbide is made for metal but can be used on most handle materials. AO is made for non-metallic materials. Both last longer when used wet but you probably wouldn't use them wet on handle material except plastics.

At 600 grit you probably aren't trying to shape anything, you're probably trying to put a finish on something. Notice how many times I say 'probably' - you didn't say under what conditions you were using the sandpaper.. Anyway, it is not uncommon when using the finer grits to finish a blade to use a piece of sandpaper for a SINGLE pass in one direction down the blade and then discard the paper. No matter how long the paper might be able to remove metal, any paper will start to dull after a stroke or two and that affects how the finish looks. So, in my view, it doesn't really matter how long the finer grit papers will last ...

[Jim Wilson111]

Using the 600 grit for straighten up the plunge line and removing any grinding marks from the plunge, saves a lot of time, then go to hand sanding. What type of grit do you use on SS and carbon steel in a 600 grit belt?
Thanks again
Jim

[Ray Rogers]

I rarely use belts beyond 400 grit, and those are the blue AO belts from Hermes.

Maybe you didn't mean exactly what you wrote but you seem to indicate that you are using 600 grit belts to clean up grind marks from creating the plunge cut. Most guys use 60 grit to grind the initial plunge and you'd be a very old man by the time you cleaned that up with a 600 belt. If that is what you're doing then you need to change your method. If your initial grind was 60 grit, follow with 120, then 220, then 400, then 600, and so on until you get where you want to go. At each step, be sure that ALL the marks from the previous grit have been removed. This way, you'll find that the finer grits will last long enough to do the job when you get to them. If you think you're saving time going directly to 600 grit I would have to predict your fiinish work may not be as good as it could be, i.e., you're probably polishing or blending over your coarse grit scratches rather than removing them.

I use the same belts for carbon and stainless. Yesterday, for instance, I had to finish a 2" wide, 11" long flat ground blade from S30V that was Rc 62. This is a murderous combination for fine belts. But, I got the job done fairly easily by using a fresh belt in each grit until I got to 400. For 400, I used a fresh belt on each side of the blade. After that, I went to hand sanding although the 400 grit finish was pretty darned good just as it was ....

[Frank Niro]

Hey Ray,
have you tried the 3M 'gator or Norzac belts for metal grinding? They are impresive for the clean cutting they do with very long life. As you said, I believe that proper use of belts means far better grinding results. Frank

[Ray Rogers]

Yes, Frank, I have used the Gator belts and like them. I have tried all the grits available in Gators but now only use the 400 grit and I don't use them on every knife. According to 3M the Gators are designed for finish work and not really for metal removal although they will do that in a limited way. Originally, I bought a bunch of 80 grit Gators planning to use them for hogging operations as I would a 60 Norton Hogger but they were in no way capable of doing that kind of metal removal. On the 400 Gator, I find they cut very well when fresh and will cut longer than my 400 Hermes belts but don't leave quite as good a finish. After the 400 Gator wears down it stops cutting almost completely but can still create a good finish if they aren't required to remove much in the way of scratches. Theoretically, you're supposed to be able to re-sharpen these belts by breaking up the surface with something hard. That does work, but the sharpness does not come close to the original sharpness and it doesn't last very long at all before it goes dull again. Still, the Gators are extremely durable and I still find uses for mine even after more than a year of use.

That's the thing about belts though, they don't work the same way for everyone. I have read statements from guys who swear Gators will remove gobs of metal but they don't when I use them. Others swear by Tri-zact and Norzac but I've never gotten much from them that I liked. I think it is always good to go back and re-visit these different belt types every few years. I have found that belts I thought were crap suddenly started working pretty good a few years later after my grinding techniques gradually changed and became more refined .....

[longhunter]

Have any of you used the ceramic belts ? the ceramic coated roloc disc's at work seem to last well when grinding on welds that need cleaned up these are very rough 36x they make quick work of things

[Ray Rogers]

The Norton Hoggers are ceramic belts. I've been using the new R980's lately, they seem to last even better than the regular Hoggers.......

[JediOkie]

Originally Posted by Ray Rogers

The Norton Hoggers are ceramic belts. I've been using the new R980's lately, they seem to last even better than the regular Hoggers.......

Yikes, how do yo uafford those? When I priced them they were $18+ ea with a minimum of 10 and the first price break wasn't unitl 50+

[Ray Rogers]

Where were you trying to buy them? Where ever it was, it was definitely the wrong place! Yes, they probably are about as expensive a belt as you can buy but they aren't THAT expensive. I don't recall the exact price but they are about $6.50 each from Tru-Grit. I buy them 10 or 15 at a time and they do not offer a price break at any level so one belt is the same price as 100 belts. I also buy my other belts at the same time which means my total bill is usually between $150 - $200. That's enough belts to last me for 3 or 4 months mostly because I work at glacial speed ...

[JediOkie]

I couldn't find them on the Tru-Grit website so I checked Norton and found that the local Fastenal store can get them and that's the price they quoted.

[Ray Rogers]

I don't know what's on Tru-Grit's website, I call them directly when I order. Give them a call and see what they say........