Blade Finish/sanding

[Theforerunner]

So up til now, I haven’t really shot for a mirror finish On my knives, and anything about “that” or anything relating, I’ve always relied on info from YouTube for so I figured I’d ask the experts;

hiw do you guys finish you blades? What steps and tools do you use to achieve these nice matte/mirror finishes? Do you do it all hand sanding? Before or after heat treat or both?

I’m always curious about easier ways to go about making my knives look nicer. I’ve read about cork belts and scotch bright belts and gator belts.. and all that sound rather expensive maybe minus the cork belt route.

if I’m not going for a rough Aesthetic
I typically just grind my blades out with 36-40 grit (maybe 80 if I’m out of blaze belts) then clean things up with 220, bring it closer to final shape and usually hand sand from there and usually end with a red scotch bright finish. I’m really Leary about taking a knife back to the belt grinder to clean it up after heat treat save for the grind lines; worried I’ll ruin the geometry

is there a better alternative to a couple hours of hard hand sanding work?

(I wanna start messing with ferric and media tumbling but that’s another topic I suppose)

 

[HSC ///]

There’s too many variables to answer you simply...
In general Finishing is the most time consuming operation. I try to keep that part down to a minimum so in general I don’t hand sand and never provide a mirror

Anyway answers to your questions depends on details like type of blade and for what knife and what style and does it have a plunge and what is the material...

 

[john april]

google steve johnson mirror finish, he is a pro at it. personally i go to 400 grit, then i use cork belts- 400, 800,1000. then i hand sand up to 3000 grit and buff. the higher you hand sand, the less time on the buffer, which means your corners will stay more crisp.

 

[J. Hoffman]

I personally don't care for the look of mirror finished blades, so I never do them. My satin finishes are done with about 20 minutes of handsanding. Scotchbrite and Gator belts are very economical. They damn near last forever. When finishing I always go one grit past what I want my finish to be. If I want an 800 grit satin finish, I hand sand to 1000 grit and then go back to 800. It leaves a very uniform finish.

 

[Mikko Pitkanen]

I personally hand sand to 600/800 grit and then take it to the buffer and polish the happy little devil out of it.

 

[DCamargo]

I tried something new on my last knife. I hand sanded to about 400 grit. Cold blued it, then stone washed it with a bucket full of yard rocks. I really like the way it came out and it really does go a long way in hiding scratches. Did this on my EDC knife so it was getting scratched up pretty good. I think this method may be my go to for a while.

 

[REK Knives]

google steve johnson mirror finish, he is a pro at it. personally i go to 400 grit, then i use cork belts- 400, 800,1000. then i hand sand up to 3000 grit and buff. the higher you hand sand, the less time on the buffer, which means your corners will stay more crisp.

I think his technique works on low carbide stuff but not on more modern steels. It really depends what you're grinding imho

 

[AVigil]

I think his technique works on low carbide stuff but not on more modern steels. It really depends what you're grinding imho

Is RWL 34 considered a "modern steel" because it sure works with that.

 

[REK Knives]

Is RWL 34 considered a "modern steel" because it sure works with that.

I'm not sure as I haven't worked with that steel much... But RWL34 has a very low vanadium carbide content so that's probably why. Blades that buff nicely would work really well with this technique though I would expect.

 

[Rhinoknives1]

I use AEBL 440c and a few of the PM Stainless Steels at times.——-I grind to 120g go to Scotchbrite Belts & then 400 & 600 Cork belts loaded with Green Chrome. A nice brush finish is my result

 

[Theforerunner]

I use AEBL 440c and a few of the PM Stainless Steels at times.——-I grind to 120g go to Scotchbrite Belts & then 400 & 600 Cork belts loaded with Green Chrome. A nice brush finish is my result

you go to scotch bright belts right from 120 grit? Wow, I guess I was under the impression that scotch bright was something more in the range of 400-600 grit strengths. I think I need to get some of these.


What do you guys do from like the start of the work though? Like if you grind profiles and grind lines with 40ish what are you doing between there and these fancy scotch bright/ cork belts and so forth? If you’re grinding up to 400 grit before hand sanding, how many different grits are you stepping up before you go there?

I typically go from 36 - 220 on the grinder then set start hand sanding right from there with 220 - 320 - 400/600 and then just scotch bright by hand to finish it off. But I feel like I still have some pretty deep scratches I can’t get out sometimes but the matte finish kind of hides it. Are scotch bright and cork belts just that damn good that they take a lot of work out of deeper scratches?

 

[Hengelo_77]

If you have deep scratches you moved up gritsize to quick

 

[Theforerunner]

If you have deep scratches you moved up gritsize to quick

I mean, I think I understand why it happened, lol. I’m just curious to other people’s methods and if there’s tips and tricks out there I don’t know about to make things easier on myself.

 

[A.McPherson]

There really aren't any "easy" ways to get rid of deep scratches. You just have to move grit to grit, removing all the previous grits scratches.

It's easier if you are doing a grind that you can change grinding direction, so that you can see the new scratches in relation to the old ones...

This applies to both hand and belts...
Just my two cents!

 

[Sam Dean]

I've been going 40-80-120 ceramic belts, then A160, A100, A45 Trizact belts. On A100 and A45, I'll tilt the blade up & down to make criss-cross scratch patterns just to make sure all the prior grit scratches are gone. If it's belt finish, I'll end it at A45 or sometimes A30 (no criss-cross pattern). If hand sanding, I'll criss-cross the A45 & don't bother with A30. I've been trying to get good results from scotch bright and cork belts, but haven't ended up with a finish I'm happy with (yet, anyway).

I use Indasa Rhynowet paper for hand sanding, and lubricate with glass cleaner. Typical grit progression, after the criss-crossed A45 belt, is 220-320-600-800-1200-800 (or 600). It always looks better if I go up a higher grit than I want to end with (1200), then drop back to the lower finish grit (600 or 800).

When hand sanding, I'll end the current grit with a swirling pattern. Then, when I move to the next grit, there's no question that all the prior grit scratches have been removed. Once the lower grit swirls are gone, I'll do the swirl pattern again, then move to the next higher grit. Also, I always use a backer block when hand sanding. Usually a piece of micarta or G10.

 

[Horsewright]

36 grit ceramic to rough in the bevel (say 50 to 60 percent). 50 ceramic to finish the bevel grinding. 120 ceramic to refine both flats and bevel. 220 A/O to refine plunge and bevels and flats and then green Scothbrite with WD 40.

 

[Hengelo_77]

Last gritsize hand sanding I now use wd40 and a rubber backer.
All prefious gitsizes I use soapy water and hardwood or brass backers.

Best time safer for finishing a blade is not trying to take shortcuts and enjoying the music that is playing.

 

[John Cahoon]

Sam D... Swirling huh? learned something new to try. +1 on the rubber backer at higher grits only I use heavy leather scrap, works great! Also wanted to mention inspection under a variety of lights and strong lenses. I recently replaced an incandescent lamp with an LED array of maybe 20 bulbs in a desk lamp and it seemed to really show 'em better than other types. Long ago someone also mentioned using a variety of lights... incan. fluor. and sunlight so that's 4 light sources and I use them all.

 

[Rhinoknives1]

you go to scotch bright belts right from 120 grit? Wow, I guess I was under the impression that scotch bright was something more in the range of 400-600 grit strengths. I think I need to get some of these.


What do you guys do from like the start of the work though? Like if you grind profiles and grind lines with 40ish what are you doing between there and these fancy scotch bright/ cork belts and so forth? If you’re grinding up to 400 grit before hand sanding, how many different grits are you stepping up before you go there?

I typically go from 36 - 220 on the grinder then set start hand sanding right from there with 220 - 320 - 400/600 and then just scotch bright by hand to finish it off. But I feel like I still have some pretty deep scratches I can’t get out sometimes but the matte finish kind of hides it. Are scotch bright and cork belts just that damn good that they take a lot of work out of deeper scratches?

You have to have a clean 120g finish. Then each company that makes “Scotchbrite” type belts can have a different color progression , from most aggressive to finest , Brown, Red, Green & Blue is what the brand I’m currently using. I go to Green & then 400 Cork that I moisten & then load with Green Chrome Buffing Compound. I learned the buffing Compound on Cork trick from hanging out with the late Bob Loveless at his shop on a couple of Saturdays

 

[J. Keeton]

36 grit ceramic to rough in the bevel (say 50 to 60 percent). 50 ceramic to finish the bevel grinding. 120 ceramic to refine both flats and bevel. 220 A/O to refine plunge and bevels and flats and then green Scothbrite with WD 40.

So good I wrote it down in my knife making notes. Thanks for sharing your methods, sir! I'll need to try out the green scotchbrite and try the WD40!

Pre HT I've been going 60 grit ceramic, 120 AO J-Flex (get plunges close here). After HT I start back with the 120 grit J-Flex, then 220 girt J-flex, then blue scotchbrite. Sometimes I got 400 before the scotchbrite. A lot of the time I acid stone-wash after this step.