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Cutty Sharp
09-15-2012, 07:16 PM
Hi guys

This is my Kiya 180mm santoku, Swedish carbon, pretty good feel and a decent performer. It's currently my go-to, especially as it's smaller than a gyuto and I've got a Korean kitchen with counter space about the size of a stove-top. I also don't worry much about what happens to this knife and have played with patinas, got it rusty, rubbed it all away, and so on again. It's kind of my knife to mess around with.

Anyway, I want to polish it. I can remove the patina pretty well with [I]Metal Glo[I] but you can still see some deeper indications of a one-time forced patina, former rust spots, as well as fine stratches in different directions from various abbrasive experiments. You can see a bit in the photos below.

I'd like to polish it up to look really shiny, not necessarily to a mirror, but enough to make it look new again, and maybe round off the spine a bit while I'm at it. For those who do this, I'm wondering what powders/compounds/finger stones/sand papers/micro meshes you've tried or'd recommend? I'm asking 'cause I'm organising a package from the US now and can buy this stuff. Have looked around, but haven't seen a definitive thread on this. (Maybe because patinas are popular ;) )

Thanks for any suggestions!

100051000610007

GlassEye
09-15-2012, 07:43 PM
I just use wet/dry sandpaper for this purpose. You will need to start at a grit low enough to remove the current scratches/grind marks then progress up to the desired finish level; use cork or rubber block to back the sandpaper so that it can conform to the geometry of the blade. I buy 3M wet/dry sandpaper, available from automotive stores.

Dusty
09-15-2012, 08:53 PM
I like the profile of your santoku, that tip looks kind of useful. I've had some success with micro mesh pads, but it requires a lot of patience.

Cutty Sharp
09-15-2012, 10:48 PM
Yes, thanks. It's a useful tip which is why I tend to grab it ahead of my nakiri, but if more space then I'll go for the gyuto. They told me this is their #1 seller in Japan, incidentally, so the kind of all-rounder home cooks there like.

dmccurtis
09-15-2012, 11:06 PM
Wet/dry paper for removing the factory scratches, then Micro Mesh MX for polishing.

Cutty Sharp
09-16-2012, 12:26 AM
Thanks so far, guys. Doing a quick search I see the micro mesh goes up to 1200 grit. Which grits do you recommend for the wet/dry and micro mesh?

If I use sharpening stones as a guide, I'd imagine higher grits than 1000 or 1200 would be needed to really finish well, no?

Mr.Magnus
09-16-2012, 01:16 AM
not rly unless your looking for a mirror finnish.

my micromeshed cleaver taken to 12k

10033

wsfarrell
09-16-2012, 01:17 AM
I have a micro mesh kit from Woodcraft that goes to 12,000 grit.

dmccurtis
09-16-2012, 03:47 AM
The different Micro Mesh series have different grit ratings. Standard series 12000 is 2 micron, MX series 1200 is 3 micron. MX is designed for finishing metal and is available in coarser grits, where the standard is more effective on plastics and wood. They also have AO (aluminum oxide) series for metal, which may be more effective on some steels, but I haven't tried it. MX 1200 leaves a hazy mirror finish, standard 12000 is a little brighter.

Von blewitt
09-16-2012, 04:07 AM
I've done it by laying a folded wash cloth on top of a stone and wrapping sheets of wet dry around the stone, lubricated with wd40 and laid the knife flat and used a motion similar to sharpening. took it from 320-1000 grit. it was quite quick, And left a nice hazy polish. Not sure it's the best way but I was pretty happy with the result.

bieniek
09-16-2012, 06:15 AM
depends on what effect youre after.

If you want to get a nice haze and mirror underneath, you would have to use fingerstones after youve worked blade out with papers first.

I would start as low as 180 wetpaper grit, go 360, 600, 800, 1200, 2000 and then mix some stone mud or fingerstone and work it from there.

This is tricky part cause while paper on cork or rubber gives you uite uniform finish, the fingerstones are not. You will have a chance to see every imprefection in the grind and every scratch left from coarser grit.

+10 to respect though... ;)

Marko Tsourkan
09-16-2012, 09:26 AM
If you going to refinish a knife, you should consider thinning it above the edge. I can see bevels from the pictures. I would thin them so your edge is not thicker than .14mm. You will see improvement in cutting performance. However, if the RC on the knife is low, going that thin would probably not be a good idea. Leave a little more on the edge then.

M

Cutty Sharp
09-16-2012, 04:21 PM
Has anyone tried 'diamond finger stones'? Found them on the site below and they look interesting, if expensive. They're measured in microns rather than grit.

http://www.nihonzashi.com/diy_supplies.aspx#Price_List

Also, thanks for that tip on the micro-mesh kit, wsfarrell. Is this what you use? http://www.woodcraft.com/product/2004014/9147/micromesh-small-sanding-kit.aspx How long do you - or anyone - find that the micro-mesh paper lasts?

... Incidentally, I was checking into micron-grit measurements and it seems this is pretty difficult for use consumers to be sure about, that with grit also one manufacturer's grit number might mean something a little different than another's, and that there might be differences between how Japanese grits are measured vs others, and so on. Whew, I hadn't considered some of this before. It's a complex world out, I guess. Anyway, not sure how many people know this (if they care).


If you going to refinish a knife, you should consider thinning it above the edge. I can see bevels from the pictures. I would thin them so your edge is not thicker than .14mm. You will see improvement in cutting performance. However, if the RC on the knife is low, going that thin would probably not be a good idea. Leave a little more on the edge then.

Thanks, Marko. RC with this one is fine I think. Bevels are not severe now but are slightly inconsistent, with a little over-sharpening at the heel and tip (hard to see in picts). I think you're right and I'll thin it out, sharpen and maybe microbevel after. Fun stuff. ;)

bieniek
09-16-2012, 04:45 PM
Has anyone tried 'diamond finger stones'?

In that size, they should be called fiststones or something :whistling:

Cutty Sharp
09-16-2012, 04:50 PM
In that size, they should be called fiststones or something :whistling:

Well, 2.5 x 5.0 cm more or less ... not so big, and 'fiststones' only if you've got a pretty small hand.

bieniek
09-16-2012, 05:08 PM
my fingerstones are 0.5x1cm or 1x1.5 i would say

Cutty Sharp
09-16-2012, 05:26 PM
my fingerstones are 0.5x1cm or 1x1.5 i would say

You're right :surrendar: I guess one of us should send a complaint message to the maker. He must have his porportions all out of whack! :cool2:

bieniek
09-16-2012, 08:56 PM
just for laughing purposes :) Maksim you see this? damn huge "fingastones" hehe

wsfarrell
09-16-2012, 09:23 PM
Has anyone tried 'diamond finger stones'? Found them on the site below and they look interesting, if expensive. They're measured in microns rather than grit.

http://www.nihonzashi.com/diy_supplies.aspx#Price_List

Also, thanks for that tip on the micro-mesh kit, wsfarrell. Is this what you use? http://www.woodcraft.com/product/2004014/9147/micromesh-small-sanding-kit.aspx How long do you - or anyone - find that the micro-mesh paper lasts?

I do have a Woodcraft kit like the one in the link. I also have the pads, like these, which go up to 12k as well. The pads seem to last a little longer than the paper, and they're great for other stuff like polishing handles.

http://www.woodcraft.com/Product/2020333/10573/MicroMesh-Pen-Sanding-Kit.aspx?reviewPage=1&Anchor=Reviews

The diamond fingerstones look really interesting. They're large, but I don't see that there would be a problem cutting them into smaller pieces. I think I'll try a couple.

ThEoRy
09-17-2012, 12:31 AM
I'll say this about grit scales, Japanese grit numbers are about double American numbers. So the micro mesh pads I use go up to 12,000 American which is about 24,000 Japanese. That's pretty frigging mirrory.

GlassEye
09-17-2012, 12:52 AM
You really don't need to go as high as some of these recommendations, in my opinion, unless you want true mirror. For sake of reference, here is a photo of a knife I sanded to 3000 grit, Tanaka damascus nakiri.
http://i821.photobucket.com/albums/zz133/glasseye72/KKF/_DSC2418.jpg

cclin
09-17-2012, 01:40 AM
hi: this maybe a stupid question? what direction when you polish the blade?:scratchhead: left-right? up- down? circling motion? or whatever you like??

GlassEye
09-17-2012, 01:49 AM
hi: this maybe a stupid question? what direction when you polish the blade?:scratchhead: left-right? up- down? circling motion? or whatever you like??

Follow the current grain/grind marks when cleaning polishing; if changing the polish, sanding along the length of the blade parallel to the edge is easier and looks better, in my opinion.

cclin
09-17-2012, 02:15 AM
Follow the current grain/grind marks when cleaning polishing; if changing the polish, sanding along the length of the blade parallel to the edge is easier and looks better, in my opinion.

some of my knife very difficute to identify the current grain/grind marks! could you tell me the grain/grind marks on these three??http://i1054.photobucket.com/albums/s482/54cclin/CIMG1354.jpg

Cutty Sharp
09-17-2012, 03:08 AM
some of my knife very difficute to identify the current grain/grind marks! could you tell me the grain/grind marks on these three??

If you can't see any marks, then I'd say you're free to polish in the direction you want. If you did have marks and wanted to change, I guess you'd have to go low grit to sand off the current marks first by sanding in the direction you want the new marks to go. But anyway, if you go through a series of grits up to a very high one then the marks will vanish. Mirror!


You really don't need to go as high as some of these recommendations, in my opinion, unless you want true mirror. For sake of reference, here is a photo of a knife I sanded to 3000 grit, Tanaka damascus nakiri.
http://i821.photobucket.com/albums/zz133/glasseye72/KKF/_DSC2418.jpg

Thanks for the photo, and you're right. That's quite a polish! Makes me think that over 3000 would just be if you've got a lot of time on your hands and not necessary. If I buy a set, though, I'll still probably try to see how it goes as a set would include lower grits, then a 3k, a 6k and a 12k and might as well use 'em.

Mr Theory said:


I'll say this about grit scales, Japanese grit numbers are about double American numbers. So the micro mesh pads I use go up to 12,000 American which is about 24,000 Japanese. That's pretty frigging mirrory.

I don't know if this is right as a few searches have shown different results on the Jpn-US correlation and made it appear very unpredictable to me, but if it is correct then 3000 grit micro-mesh would be 6000 with a Japanese stone, which of course does give a nice polish on an edge and I think would be fine for me.

Here's one listing from user Smokintbird on straightrazorplace.com:

http://www.straightrazorplace.com/forums/attachments/advanced-honing-topics/28976d1250005383-abrasive-grit-comparison-sheet-grit-comparison-aug-11-2009.pdf

Other sources show various results grit comparison results, so I don't know what to think and am not too concerned. If the above is how a 3000 looks then sounds good.

Birnando
09-17-2012, 04:44 AM
I don't know if this is right as a few searches have shown different results on the Jpn-US correlation and made it appear very unpredictable to me, but if it is correct then 3000 grit micro-mesh would be 6000 with a Japanese stone, which of course does give a nice polish on an edge and I think would be fine for me.

Here's one listing from user Smokintbird on straightrazorplace.com:

http://www.straightrazorplace.com/forums/attachments/advanced-honing-topics/28976d1250005383-abrasive-grit-comparison-sheet-grit-comparison-aug-11-2009.pdf

Other sources show various results grit comparison results, so I don't know what to think and am not too concerned. If the above is how a 3000 looks then sounds good.

Yes, the grit conversion between various standards, and materials, is a right mess:)

Both in polishing and honing it is about testing and trying various systems until one finds what does the needful really:)

TB_London
09-17-2012, 01:01 PM
some of my knife very difficute to identify the current grain/grind marks! could you tell me the grain/grind marks on these three??http://i1054.photobucket.com/albums/s482/54cclin/CIMG1354.jpg

Remember if you polish Damascus you'll need to re etch to get the pattern back

keithsaltydog
09-18-2012, 01:38 PM
Wet dry paper is inexpensive,also an autobody trick is sanding in one direction,not equal pressure back & forth,,like trail edge sharpening or leather strop.Polished out the Polyurethane on a Koa table to 2000 using this tech.

Burl Source
09-21-2012, 06:08 PM
Wet dry paper is inexpensive,also an autobody trick is sanding in one direction,not equal pressure back & forth,,like trail edge sharpening or leather strop.Polished out the Polyurethane on a Koa table to 2000 using this tech.

PHOTOS PLEASE

JasonD
09-22-2012, 12:38 AM
^ What he said.

keithsaltydog
10-18-2012, 06:45 PM
https://plus.google.com/photos/100198520394700008527/albums/5800781350052680209?authkey=CMmWk62c_sXI9AE

Dave Martell
10-18-2012, 09:38 PM
https://plus.google.com/photos/100198520394700008527/albums/5800781350052680209?authkey=CMmWk62c_sXI9AE


https://lh6.googleusercontent.com/-7PWMYtW0WPU/UICD7Q0EonI/AAAAAAAAAAc/hMmQa1R0OX0/w387-h516-p-k/Koa%2BTable%2B1.JPG