Pre and post heat treat belt grits?

Hawk45

Hawk45

Joined
Jan 28, 2005
Messages
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What is your preferred belt grits to use pre heat treat and then post heat treat of carbon blades?

Just starting I've been using the following, let me know if I should be adding or removing any grits anywhere:

Pre HT:
36 grit Zirconia - Grind out blank
60 grit Blaze - touch up blank and start the blade grind
120 grit Blaze - take out 60 grit scratches and clean up
320 grit Gator - take out 120 grit scratches

Post HT:
120 grit Blaze to clean off scale
320 grit Gator - clean up 120 scratches
600 grit Ceramic - clean up 320 and get nice finish
For high polish move to hand sanding with finer grits.
 
Personally, I wouldn't worry about going to 320 before heat treat. 120 is plenty since you'll be going to 120 after HT anyways. People look at me funny, but AO 60 grit belts hot metal off just fine pre HT. They also do a good job at roughing out the profile. After HT I go to the newest and sharpest belts I have (not AO) and work my way up through the Gator belts.
 
I used 36 before I got my band saw and cut out my blanks with a jig saw. Now I rough out with a 60, touch up with 80 and finish with 120. Then I switch to hand sand 220/320 before HT. After HT its all hand sanding unless I have major scale. I start at 320 for a quick check and may drop to 220 if needed, then up from there. I don't touch the belt again until sharpening, then its just a quick run to set the edge and on to stones.
 
Pre HT 50 then 120J flex in ceramic.
Post HT 80 then 120 ceramic and gator if I decide to go that high.
CW
 
We start with Aluminum Oxide 36 grit belts from Industrial Abrasives, cost about $1.30 each, when you buy a dozen they throw in a dozen free. I use them for all major jobs, they don't last for a long time, but when I tested them against the more expensive belts, the expensive belts cut well for a short time, then I would waste time with a belt that had lost its aggressive cut, wasting time. It is not hard to throw a cheaper costing belt away and start with a fresh one.

We usually purchase 6 dozen at a time.

I always finish to 220 grit before hardening.
 
Ed, can you provide the website info? When I google industrial abbrasives, tons of things pop up. Thanks a bunch for the cheap belt tip :thumbup:
 
David, I'm not sure which ones he uses, but the 707JE belts from 3m are essentially their cubitron abrasive on a j-flex backing. They're a very thin layer of abrasive and wear out fairly fast but hold up better than the AO versions.

Ed, thanks for the #, I remember you mentioning that a while back and then forgot about it but had wanted to try it out. At those prices the shorter life span is unimportant. As you said, use and toss when they're no longer fresh and sharp without that cringe of tossing a more expensive belt. In the finer grits I would want something different, but for that 36 grit, tear metal off and get to shape... I tried the sairon belts and they were ok, but they're still not THAT cheap.
 
Dave
I am sorry I meant xflex in ceramic. Hermes makes a good one I like to use CN 466 xflex
Its just a tad bit stiffer than a Jflex and I actually prefer it to a Jflex now.
CW
 
Thanks for the feedback everyone.. good stuff. Being new I bought all makes and grits to see what I like.. now trying to narrow down the belts to what works for me.

Ed, I'm going to grab some of those to try out.

I'm finding myself doing some thicker knives now (3/16", 1/4") and the 36 grit get lots of grinder time.. for shape and primary bevels
 
You are correct! Thanks, I am just a poor old broke down knife maker, not great at numbers. Still a good buy.
 
Thought Id order a box of their scrap and see how it works out. Lots of sizes in the box, I ordered their medium assortment.
 

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