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Polishing the face of a knife?

b
brokentelephone Nov 13, 2010 01:37 AM

Hi --

I scratched up the sides of the knife very badly in a sharpening experiment when I was firsts learning to sharpen.

Anyhow -- I've essentially stopped using the knife because it looks so bad, and was wondering if anyone knew how to polish/sand/resurface a knife?

Thanks --

  1. Duppie Jun 21, 2012 08:47 AM

    Try Flitz, who now has a Knife polishing kit. I've been using it for years for cleaning and polishing gun barrels,stainless and chrome.

    1. tanuki soup Nov 13, 2010 04:28 PM

      I'd suggest using a "rust eraser". I scratched up the sides of a knife trying out a highly touted wheel-type sharpener. (The experience led me to bite the bullet and teach myself how to use proper waterstones.)

      The rust eraser feels like a block of gritty hard rubber. It really does "erase" scratches and remove rust spots. After using the eraser to remove the scratches, a final polish with liquid cleanser on a folded up damp paper towel will give you a gleaming satin finish rather than a bright mirror finish. Quite attractive actually, and no more ugly scratches.

      I use one sold by Kai (the company that makes Shun knives, and also many other kitchen goods here in Japan). A similar "Japanese Rust Eraser" is available from Amazon.com in the US:
      http://www.amazon.com/Rust-Eraser-Mad...

      1. t
        The Loaf Nov 13, 2010 11:04 AM

        If it's of any use, here's a link to a thread about this topic recently posted on the Knife Forums board.

        http://www.knifeforums.com/forums/sho...

        1. scubadoo97 Nov 13, 2010 04:45 AM

          If they really bother you, you will need to work hard to remove them. The reason being that you can not use a polishing compound with a grit much finer than the one that created the scratch as this will take you forever and if it's coarser the final polish on the knife you will still induce new blemishes

          It is often best to first use a coarse grit at least equal to the one that created the scratch and scratch up the knife uniformly and then reduce the grit size until you get to the finish you want.

          You might actually like the brushed finish and may not want to take it too far down to a polish.

          I've done this with a couple of knives when I inadvertently scratched them up

          Like Chemicalkinetics, I find that a few scratches don't bother me anymore.

          2 Replies
          1. re: scubadoo97
            Veggo Nov 13, 2010 05:24 AM

            scuba, you inspired my to scrub up my 22 year old Wenoka dive knife that was getting a bit skanky and a stainless steel scrubbing pad and some elbow grease has it shining like a new dime - thanks

            1. re: scubadoo97
              Chemicalkinetics Nov 13, 2010 05:45 AM

              "scratch up the knife uniformly "

              Agree.

            2. Chemicalkinetics Nov 13, 2010 03:40 AM

              broken,

              Hi, It is very common to scratch up the side of the knife. At first it brothers me, but now I view it as a signature and a badge of honor. Similar to the fact that I have a lot of respect when I see a person own a block of knives from various manufacturers.

              The more polished the original blade is, the worse a scratch looks. Similar to the fact that white looks whiter on a black background. The challenge of polishing a scratch is that you will start to scratch up the rest of the blade. If you don't mind, you can always start polishing with your stones and progressively going up to higher grit number -- assuming you have a set of stones. At the end, you can finish with a polishing compound like this:

              http://blueroofdesigns.files.wordpres...

              The problem is that you may not able to get as shiny as the original surface.

              Be careful about polishing the knife with a power tool. I don't mean that not using one, but be careful because you can overheat the knife and ruin the steel.

              19 Replies
              1. re: Chemicalkinetics
                Chemicalkinetics Nov 13, 2010 05:45 AM

                Forget the polishing compound... if you have a high grit stone.

                One hint, make sure you add plenty of water if you are using a waterstone. The reason is that when you are grinding the entire blade flat, you will constantly push the water out of the stone. When polishing on a very muddy or dry waterstone, you get a very "mist" finish, which is great if that is what you want and many people prefer that. If not, you will need a lot of water to get a polished finish. By "mist" finish, I am borrowing the Japanese term: Kasumi, which has a finish like this:

                http://ecx.images-amazon.com/images/I...

                1. re: Chemicalkinetics
                  cowboyardee Nov 13, 2010 11:02 AM

                  Chem, a waterstone would be my polisher of choice on a large flat bevel of a knife like the inage you posted. But I'm guessing the OP scratched up the sides of a more traditional convex-ground chefs knife. If that's the case, the OPs best option will be wet/dry sandpaper starting at around the grit that made the scratches and then working through higher grits (doubling or so with each step) until the desired level of polish has been obtained.

                  Warning to the OP - this can be more work than it sounds like. Are you sure the scratches bother you that much?

                  1. re: cowboyardee
                    Chemicalkinetics Nov 13, 2010 12:47 PM

                    You are correct. Sandpaper will work better for any knife shape. I also agree with you that it will require a lot more work just an hour. It can take a long time. The problem is that as a person try to polish the scratch part, the nearby surface will get scratch up by the sandpaper, so now there are more to work with.

                2. re: Chemicalkinetics
                  Delucacheesemonger Jun 18, 2012 12:43 AM

                  As l now noticed you write a bit on Philadelphia board, do you know a place in or near Philadelphia l can use to polish knives. Do not need them sharpened, just polished. There are quite a few collector's knives from France that are old carbon steel and look a bit less than stellar. Any help appreciated. Would the liquid cleanser as mentioned below work ? If so, what cleanser would that be?

                  1. re: Delucacheesemonger
                    Chemicalkinetics Jun 18, 2012 01:24 AM

                    Sorry, I don't know any knife polisher. Dave Martell is a renounced knife sharper and he offers knife surfacing work:

                    http://www.japaneseknifesharpening.co...

                    However, Dave does not live in Philly. He lives in Fleetwood, PA.

                    If you just want to remove the light oxide or rust, then I would give Bar Keeper's Friend and a brush a try. Alternatively, you can use a very fine sandpaper mentioned by cowboyardee or the rust eraser mentioned by tanuki. The sandpaper and the rust eraser are more aggressive and will resurface the knife blade much quicker. However, they also lightly scratch the knife blade. So if you expect a mirror surface knife blade, then you are out of luck.

                    Hopefully, someone else knows a Philly knife sharpener who does blade resurface work.

                    1. re: Delucacheesemonger
                      scubadoo97 Jun 18, 2012 05:29 AM

                      First, is it just natural patina on those French knives? If so you should let it alone. If you're looking to remove a lot of oxidation/patina a product like soft scrub or Bar Keepers Friend will work to remove a lot of it. 1500 grit or higher wet dry sand paper will also work. Try to use the least aggressive method then you can use a metal polish compound to bring back the luster.

                      1. re: scubadoo97
                        Delucacheesemonger Jun 18, 2012 06:43 AM

                        These are carbon steel knives in perfect shape, the patina is natural and looks like a Dexter chef's knife from that period, 30's-60's, with various colors and lites and darks that are completely normal.
                        When l buy an old knife it comes sometimes polished, thus back to a new matte-like finish without 'waterstains' or other colorers. In Paris l have had an old one polished and it looks like new, not shiny almost matte but new.
                        That is what l am looking for. This guy here took the knife on a buffer wheel, a huge one, and in 20 seconds the blade looked great.

                        1. re: Delucacheesemonger
                          k
                          kaleokahu Jun 18, 2012 07:33 AM

                          Hi, Delucacheesemonger:

                          You are making a good case for having your own buffer, wheels and rouge. Just polish *off* the edge.

                          Aloha,
                          Kaleo

                          1. re: kaleokahu
                            Delucacheesemonger Jun 18, 2012 07:47 AM

                            Actually bought a small wheel with buffer for a Dremel, wrong size did not fit, gave up.

                            1. re: Delucacheesemonger
                              k
                              kaleokahu Jun 18, 2012 08:14 AM

                              $40 gets you this: http://www.harborfreight.com/6-inch-b...

                          2. re: Delucacheesemonger
                            j
                            JavaBean Jun 20, 2012 11:21 AM

                            Hi, Delucacheesemonger

                            I’ve always been curious about older carbon steel knives and would appreciate learning about some your favorites brands/makers and restoration projects.

                            1. re: JavaBean
                              k
                              knifesavers Jun 20, 2012 12:13 PM

                              Many old blades have serious over sharpening, rust, wood damage or other difficult issues to address.

                              Once any cancerous rust is removed there may be deep pitting and this has its own degree of difficulty. The sad thing is not enough people want them and are willing to pay for restoration efforts. Sharpening is the last thing in the process.

                              Old cleavers can be nightmare to fix. It can be more like auto body work than knife sharpening. I have a Briddell that took about an hour to reshape due to a deep gouge in the middle. I also have an Old Hickory cleaver that the rust pits are so deep it may be beyond salvage.

                              Jim

                              1. re: knifesavers
                                j
                                JavaBean Jun 20, 2012 12:50 PM

                                Unfortunately, the ones I've seen at garage sales and flea markets were like that.  Encrusted with so much rust and pitting that I wasn't sure if the metal underneath was any good. 

                              2. re: JavaBean
                                cowboyardee Jun 20, 2012 12:29 PM

                                http://chowhound.chow.com/topics/808731

                                The above is a thread where I discussed fixing a very common problem on vintage knives - an inward-curving edge or 'regrind' caused by years of sloppy sharpening.

                                http://chowhound.chow.com/topics/8241...

                                And this is a thread where Eiron talked a bit about reshaping and polishing the handle on a vintage knife.

                                1. re: cowboyardee
                                  j
                                  JavaBean Jun 20, 2012 01:17 PM

                                  Great threads. Thanks. I got an old carbon sabatier off of eBay as my first restoration project "gunea pig". It's got some surface rust, minor pits, a cracked handle, poor grind. Hopefully it will be fun fixer-upper or at the very least a learning experience.

                                2. re: JavaBean
                                  Delucacheesemonger Jun 20, 2012 01:03 PM

                                  My kitchen knives range from Dexter chef's knives, 6,8,10,14 inches, to a passel of knives l got on a trip to Toledo Spain as well as a lot of odd cheese knives both from Italy and Gruyere, Switzerland, and a bunch of deli fish knives from the 40's, plus way too many more.
                                  My main focus and the point of this post is a collection of French country knives from the 1880's to the 1960's, after that period most makers made the knives with inox or stainless steel. These are mostly Laguiole, with some Mongin, and Nontron thrown in.
                                  If you want info on restauration the gentlemen of this board are Cowboyardee and Chemicalkinetics who really know their stuiff and explain it well to lay people as l am.

                                  1. re: Delucacheesemonger
                                    j
                                    JavaBean Jun 20, 2012 01:32 PM

                                    Thanks for sharing. How do those dexters compare to sabatier or others from the same period?

                                    1. re: JavaBean
                                      Delucacheesemonger Jun 20, 2012 10:50 PM

                                      They have rosewood handles, a far thicker blade, perfect balance, as you can see l love them. Right now there are a bunch on ebay, number 48910, 48912, etc. The 489 is the model the number (s) following is the length of the blade.

                                      1. re: Delucacheesemonger
                                        j
                                        JavaBean Jun 21, 2012 08:14 AM

                                        Thanks. Good to know they are on the stout side. While their chef’s knives look very nice, this http://www.ebay.com/itm/Huge-Vintage-... really caught my attention. I think my friend who hunts & butchers wild animals could really use it.

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