Scratch removal after HT on monosteel blades

Hello. I am looking for some advice how to improve the sratch removal process after HT . My current grinding process (still with 1x30" baby grinder) looks as follows:

1) cut out the blank
2) grind to about 80% with 40/60/120/240 belts
3) send out for HT
4) finish grinding with 40 grit belt up to about 95%
5) use 60 and 120 belts to finish the grinding
6) make sure that after finishing with 120 grit there are not older scratches left (I use different angle between the blade and the belt)
7) continue with scratch removal / surface finishing of the blade

Up to the point 6 this works rather OK. But even the #120 ceramic belt (Norton Blaze) leaves (in particular when the belt is fresh, the scratch pattern becomes considerably finer after some 10 - 15 minutes of grinding) scratches that I have hard time removing.

I have followed the 120 belt with 3M Trizact Gator A100 (should be around grit 180) and I an getting nowhere. I must be very careful as this blade can heat up the blade easily, so only very little pressure can by applied. I have spent nearly 1 hour with A100 on one side of a 180 mm Niolox blade and I am still not done

I am sure there must be a more efficient (and consistent way) to do this. I would very much appreciate any advice or :help3:

Thank you

Matus ,
Niolox is tough to finish , doesn't get as shiny as easy like fine grained Aebl or rwl34 .
You may want to take the blade on to finer belts 240-400 and may even want to try grinding on an angle with a fine belt to just to see the scratch pattern and see if there are still deep scratches
I am working on 2 niolox gyutos 270 and 280 , thy chew up the belts crazy , twice the time and effort of Aebl

Thank you Mert. Yes - Niolox really east belts fast. My main problem here is to get past the ceramic 120 belt in the scratch removal progression. 3M A100 does not seem to manage to do that. I am wondering what would be the correct belt progression. There are no 220 ceramic belts (that I am aware of, in particular in 1x30" size).

Yeah the 1*30 will limit your choices , I found the a series hides scratches due to the pattern of the abrasives and the scratch pattern it provides vs grinding the previous ones off

Matus maybe carls.nu for finer belts? Regular ao will do the job. Also the edm stones should be good for you.

Thank you guys. I have literaly just returned from customs with 180, 320 and 600 EDM stones (5 of each) and will test them soon. But I will have a look at those AO belts too. Price looks OK.

Just a quick question - if I have 120 ceramic belt finish on the blade - which grit AO belt should be the next step?

Difficult to say what will work best for you. I do 240, with elmax I will probably go to edm stones right from 120.

Thansk. I guess some testing is due.

Robin - do you use the polishing stone like you would use a strip of sandpaper on a support or just the short side? I am wondering whehere I should break or cut the stone in 3 or 4 pieces and then glue to a piece of wood or something.

I use the short side, dressed diagonal crossection so to say. I don't break, i just have a clamp for holder.

Thanks. I was not sure, but that is how it looked in your FB post. I am only a bit worried of crearting 'dips' in the blade with such a small contact area. I guess I will try both approaches.

Yes it's a blessing and can be a curse haha. For me it's great, just keep track of how/where you're working and it does well.

chefcomesback said:

....and may even want to try grinding on an angle with a fine belt to just to see the scratch pattern and see if there are still deep scratches

Click to expand...

There's many ways to skin this cat but using the above quoted recommendation is the best way to make sure that you're deep scratch free before moving on up the line.

I go through to 120x ceramic and then use an A300 Gator diagonally, this will show what I need to grind out. Sometimes I can use the A300 gator to remove the scratches and other times I put the 120x ceramic back on and go diagonally with this and then switch back to A300 Gator straight grinding to remove the 120x diagonal scratches. This makes for a worry free end result.

Thank you. A300 Gator would be like 60 - 80 grit. If that is needed to get out scratches from 120 ceramic belt, than it is no wonder that I did not get too far from A100 I guess.

Since I have started this thread I would like to mention where do I stand after few more blades. My current (and still very much changing and developing) process is the following:
- grind the blade on #36/40 grit belt down to about 95% (ca 0.3 mm on edge)
- use #60/80 grit belt under angle to make sure all the 36/40 scratches are gone
- use the #120 belt under 'normal' grinding direction to clean up the previous stage
- use Bester 220 to remove all the scratches from #120 belt
- Set the final bevels with Watanabe AI#1000 (if necessary start with Bester if there is too much steel to be removed)
- Clean up the blade with AI#1000 and then follow up with Gesshin 4000
- go to #600 or #800 sandpaper and only clean up the blade (I do not change directions anymore, just make sure I like the result)
- If necessary go to higher grits with sandpaper

This seems to work reasonably fine. It still is a lot of work - in particular with Niolox steel (Damasteel was SO much easier to work with), but I seem to get pretty consistent results. I find that the advantage of using stones is that I have much larger steps in grit what makes it easier to see unremoved scratches. Another big advantage is that I will not overlook any low spots - If I want to get homogeneous finish with a stone - there can be basically no low spots left. And since the quality of my grinding still leaves quite a bit to be desired, I can fix some smaller flaws in the grind with the stones.

I am all ears for possible improvements