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welshstar
11-20-2011, 11:30 AM
Hi

What is the best way to clean up sharpening scratches please

No comments about not making them being the best way please !!!!

Alan

NO ChoP!
11-20-2011, 11:34 AM
On a flat blade, you can just use an 8k or better, or use fingerstones for a vex, or even Flitz in some cases...heck, even sandpaper in varying grits.

welshstar
11-20-2011, 11:38 AM
Sandpaper only seems to goto 2500 grit, how would that do on the blade ?

NO ChoP!
11-20-2011, 11:46 AM
It's a good start if your blade is all miffed up. Sanding in a single direction up a progression will get you to a uniform haze, at least.

I have a Tojiro pro with super soft cladding that had horizontal scratches from a guard, that drove me crazy. I used this technique, and finished on the whetstones, to a nice semi-mirror.

rulesnut
11-20-2011, 01:02 PM
Sandpaper only seems to goto 2500 grit

Sandpaper gets much finer than that. Micro Abrasives (http://www.leevalley.com/en/wood/page.aspx?p=33004&cat=1,43072)

Johnny.B.Good
11-20-2011, 01:16 PM
This is a question and not a recommendation, but what about a buffing "pad" attached to a drill with a little chromium oxide on the blade?

http://www.homedepot.com/h_d1/N-5yc1v/R-100671748/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053

Dave Martell
11-20-2011, 02:14 PM
The truth is that nothing really gets rid of them short of re-sanding the entire blade with something coarser than what caused them. I've tried every trick and found that the hard way is the only way if you want it to look good.

EdipisReks
11-20-2011, 03:10 PM
The truth is that nothing really gets rid of them short of re-sanding the entire blade with something coarser than what caused them. I've tried every trick and found that the hard way is the only way if you want it to look good.

i learned that the hard way too.

welshstar
11-20-2011, 03:29 PM
The buffing pad sounds like an easy option but im guessing its not, its never that easy !!

Eamon Burke
11-20-2011, 04:19 PM
The truth is that nothing really gets rid of them short of re-sanding the entire blade with something coarser than what caused them. I've tried every trick and found that the hard way is the only way if you want it to look good.

+1
Remember, after the bevel is set, a lot of knife sharpening is fundamentally the same as polishing!

Johnny.B.Good
11-20-2011, 04:26 PM
The buffing pad sounds like an easy option but im guessing its not, its never that easy !!

I still wonder what would happen to a relatively "clean" (no deep scratches) blade surface. Mirror polish with no elbow grease? I'm sure you're right - it's never that easy!

EdipisReks
11-20-2011, 04:28 PM
i would be hesitant to use a buffer, as i'd be afraid of the knife getting too hot.

Benuser
11-20-2011, 04:29 PM
Start with coarse sandpaper (e.g. P240) and experiment with adding some mud from your stones once your paper gets smoother.

Lefty
11-20-2011, 04:36 PM
You can get damned close to a mirror polish with 2500 grit. We're talking sub-micron grit here.

EdipisReks
11-20-2011, 04:39 PM
You can get damned close to a mirror polish with 2500 grit. We're talking sub-micron grit here.

hell, my most recent bright mirror was done with 320 grit norton sanding pads. it's all in the elbow grease and attention to direction. it's not scratchless, but, if i shaved, i could shave in it.

Benuser
11-20-2011, 04:41 PM
You can get damned close to a mirror polish with 2500 grit. We're talking sub-micron grit here.
But deep scratches will remain. And why one would wish a mirror polish? Food would stick.

rulesnut
11-20-2011, 04:44 PM
2500 grit is not even close to mirror.

2500 grit is 8 micron.

EdipisReks
11-20-2011, 04:45 PM
2500 grit is not even close to mirror.

2500 grit is 8 micron.

it really depends on what you mean by mirror. if you mean aluminum vapor deposited on glass, well, you aren't going to be satisfied with anything other than aluminum vapor deposited on glass. if you mean bright reflection, you can get it with just about any grit, given sufficient elbow grease.

rulesnut
11-20-2011, 04:49 PM
8 micron is approx. 2000 grit waterstone.

EdipisReks
11-20-2011, 04:50 PM
8 micron is approx. 2000 grit waterstone.

yes. and?

rulesnut
11-20-2011, 04:52 PM
and surely you are not suggesting that 2000 grit waterstone is anything close to mirror finish.

EdipisReks
11-20-2011, 04:53 PM
see post #18.

rulesnut
11-20-2011, 04:58 PM
and then?


http://www.youtube.com/watch?v=K7luMp6lb9M

EdipisReks
11-20-2011, 04:58 PM
read it. too bad there isn't an ignore function, i'd get to use it now.

EdipisReks
11-20-2011, 05:00 PM
And why one would wish a mirror polish? Food would stick.

it really depends. on a convex grind, a bright polish can improve feel while cutting, i've found.

Benuser
11-20-2011, 05:12 PM
it really depends. on a convex grind, a bright polish can improve feel while cutting, i've found.

On a very convex one, which therefore has to be quite thick.

EdipisReks
11-20-2011, 05:17 PM
On a very convex one, which therefore has to be quite thick.

i wouldn't say very convex. a little bit goes a long way. this is the combo i have on my Shigefusa, and it works wonderfully.

RRLOVER
11-20-2011, 05:30 PM
8 micron will get you really,really shiny.I don't think water stones are relevant.My 5 micron belt is very close to mirror.

Lefty
11-20-2011, 06:11 PM
Just thought I'd show this page.
http://www.leevalley.com/en/wood/page.aspx?p=64715&cat=1,42500
Note the micron sizes for each grit. I'm pretty sure we can get a mirror polish with these...however, Dave is 100% right (and Mario and Edipis), start with coarser and work to finer to get rid of the scratches.

Mike Davis
11-20-2011, 07:24 PM
Maybe this will help.
http://www.bladeforums.com/forums/showthread.php/892583-hand-sanding-video-a-couple-tips

rulesnut
11-20-2011, 07:36 PM
The OP suggested that sandpaper only goes to 2500 grit. Automotive sandpaper that is purchased in a hardware store goes by "P" grit.

P2500 sandpaper in nothing like the micro-mesh abrasive (which uses "A" grit sizes) to which you have linked.

You are correct that 2500A micro-mesh will get you very close to mirror polish.

NO ChoP!
11-20-2011, 07:58 PM
I think a mirror polish is a good option for those not a fan of patina in terms of stain resistance; albeit a touch higher maintenance, maybe.

ThEoRy
11-20-2011, 10:00 PM
On a very convex one, which therefore has to be quite thick.

Like my konosuke mioroshi deba. Mirror polish, thick, no problem with sticking. Gyuto may be different though.

slowtyper
11-20-2011, 10:47 PM
I'll probably try the sandpaper thing or micromesh pad thing next week on my gyuto. I would like to make the knife face look better because i scratched it up a lot learning how to hit the edge correctly. Its beautiful at the heel but once it starts curving it looks really funny. What is the best way to go about this? Tape the bevel and go at it? or just go at it and sharpen again (carefully) after?

Also, even though tons of people say mirror finish is not worth it I still want to try....I think everybody wnats to try it once....I may not though,l depends if I have the willpower to stop sanding!

EdipisReks
11-21-2011, 10:23 AM
go at it and then sharpen it again. remember that you have to get all of the original scratches out first, so you'll have to start with fairly coarse paper.

SpikeC
11-21-2011, 02:08 PM
If you use a powered buffer be prepared for the blade to fly across the room, possibly after going though you!

stevenStefano
11-22-2011, 07:55 AM
I have a question. How scratched up are everyone's knives? The ones I haven't thinned, there is maybe a few light scratches a little up the blade where my hand wobbled a little but they are barely noticeable. I ask this because I have seen on other forums the odd time someone posts a knife in BST and says there are a few light scratches and they seem very noticeable to me and are halfway up the blade. Is this usual or are everyone's knives more like mine where there is the odd scratch here and there? Just curious

EdipisReks
11-22-2011, 08:00 AM
other than thinned knives, i have the odd scratch here and there, mostly caused by very muddy stones abrading right above the bevel. when i first started out, however, it wasn't quite the case. i agree that often times what are described as "lightly used" or "slightly scratched" in a for sale ad are actually pretty heavily used and very un-slightly scratched!

Mike Davis
11-22-2011, 09:23 AM
I would suggest the utmost respect and care when dealing with a powered buffer. It is the most dangerous machine in the shop and has probably caused more injuries than all other machines combined.

mr drinky
11-22-2011, 09:39 AM
I have a range of the yellow-backed, wet-dry 3M automotive sand paper that I have used progressively to get rid of scratches. It took a while, and you'll need to concentrate to keep a consistent scratch patter. Get a good vise. I then have some micro mesh pads if I want to take it up a step into mirror territory. Also some steels are more abrasion resistant and will take longer yet.

k.

JohnnyChance
11-23-2011, 04:36 AM
I have a question. How scratched up are everyone's knives? The ones I haven't thinned, there is maybe a few light scratches a little up the blade where my hand wobbled a little but they are barely noticeable. I ask this because I have seen on other forums the odd time someone posts a knife in BST and says there are a few light scratches and they seem very noticeable to me and are halfway up the blade. Is this usual or are everyone's knives more like mine where there is the odd scratch here and there? Just curious

Depends on the steel. The softer and/or clad ones are pretty scratched up. My DT ITK has scratches on the left side from parsley stems and all sorts of stuff. My Hiro suji has a ton of scratches on the right hand side from salmon spines. My Shige has a couple small scratches from god knows what. My solid carbon knives seem to get less scratches.

I would refinish them, but meh, they would just get scratched again.

Benuser
11-23-2011, 05:14 AM
Your solid carbons don't have less scratches, they have patina!

JohnnyChance
11-23-2011, 05:23 AM
This is true, but even when I remove the patina or look carefully/closely, the aren't as scratched as my clad knives.

NO ChoP!
11-24-2011, 12:42 AM
I understand that the cladding is for higher stain resistance, but still, does it have to be so soft? Are all clad knives prone to such scratching. The few I have, have turned me off...

Benuser
11-24-2011, 01:30 PM
Another function of the clad is shock absorption. Imagine the 0.5mm Aogami Super core in a Hiromoto AS without the soft clad of 2X 0.75mm. Would it survive in any kitchen?

JohnnyChance
11-24-2011, 06:08 PM
And the softer steel is easier to work with and finish. Shigefusa would not be able to shape their blades they way they do if the cladding was hardened as much as the core is.