How to get scratches off a blade.

[AK Jim]

First I want to thank everybody for all the great info you have posted! Second I want to chastise all of you for not mentioning how addicting this knife sharpening and forum is !!!
I purchased a old Scrade 15OT lots of scratches see before pic. Before I go off the deep end(did I mention Addictions) a few pointers on how to proceede would be appreciated. I know this isn’t a Total Wicked edge process but you guys are so darn good at this. I did start and have a great edge now presentation?
Thanks

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[Steven N. Bolin]

First I want to thank everybody for all the great info you have posted! Second I want to chastise all of you for not mentioning how addicting this knife sharpening and forum is !!!
I purchased a old Scrade 15OT lots of scratches see before pic. Before I go off the deep end(did I mention Addictions) a few pointers on how to proceede would be appreciated. I know this isn’t a Total Wicked edge process but you guys are so darn good at this. I did start and have a great edge now presentation?
Thanks

Haha. Addicting indeed.l! Are you looking to get the edge polished up and/or the entire knife?

[CliffCurry]

First thought that came to mind was to acid/stone wash it, then mirror or satin polish the apex bevel. Or…for the blade itself you could just use scotch brite pads on a bench grinder or many other options…

[AK Jim]

The entire knife. I started with sand paper it seems like that will be a long process. I like Cliff’s suggestion of the bench grinder! Now to save some pennies for one and learn some more

[Gregg776]

If you are attempting to mirror polish the entire blade, it is going to take a lot of time and patience. Since you already started with sandpaper, you may want to continue with wet sanding finer and finer grits through the well used 800 grit level. Keep in mind that new sand paper scratches a lot deeper than used.
I personally use cloth buffing wheels after getting the profile I like with a belt sander. I have a bunch of different wheels to keep the compounds and grits separate. The wheels stitched to near the outer edge are what I prefer and I stack several together until I get about an inch wide buffing surface.
There are two types of buffing compounds.
One type has grit held together with water based glue that forms a flexible coating on the wheel. These are available in most grit sizes and cut fairly aggressively when first applied; a light touch on newly applied compound is recommended. These compounds don’t polish; they remove metal and by using progressively finer abrasives will get the blade to where the next type of buffing compound will polish out the fine scratches these will leave. These compounds come in plastic sleeves like a sausage and if they dry out can be reconstituted by placing them in a zip lock bag with a damp paper towel. I keep mine in zip lock bags in the refrigerator with paper towels around them dampened with water and a little bleach in the water to keep them from getting moldy.
The other type of buffing compounds has the grit embedded in wax. These come in bars and a myriad of totally unexplainable names and designations. My advice is to avoid the cheap Chinese compounds that have no real quality control over grit sizes [like those sold by Harbor Freight]. There are a number of name brands that you can look up their relative grit and use data on their respective web sites. Sometimes you can get great deals on eBay. I have some green compound designated for stainless steel that works quite well followed by a white fine rouge compound.
For the areas close to the handle, a moto tool with hard felt tips and the same compounds will get you into tight corners with your polishing.
If you want to blend the polish marks by hand, try Simichrome polish.
You will want to buy a buffer over a bench grinder if you are buying a machine. To polish knives you need the wide spacing of a buffer as opposed to the wheel too close to the motor housing. Harbor Freight has an 8 inch combination grinder buffer for $80 that is a good hobby machine for the price [find a 20% or 25% off coupon for Harbor freight]. Just get rid of the grinding wheel that never will balance and put on a scotch-brite wheel instead. Eastwood has a 10 inch two speed buffer and Grizzly Tools lists buffers worth considering; then there is always Craigslist.
If you use a buffing machine, be very careful. The buffing wheel can grab the knife out of your hand and do major damage to you, your surroundings and the knife. Wear gloves, a full face shield, dust mask and leather boots [at least]. Never ever lead the edge or point into the wheel.
–Gregg

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[tcmeyer]

Gregg has a lot of good info there. One thing I’d like to add is that if your goal is a truly flawless finish when sanding or polishing, with each grit change you want to shift the line by about 45 degrees. I rotate back and forth: zero, +45, zero, -45 and repeat. You don’t want to move on to the next grit until every tiny bit of scratch from the previous grit is gone. An old friend who went to gunsmith school said it was the technique they taught for a “Matchless” finish. If you are consistent and keep track of the grits you use, you can usually tell which grit to go back to when a scratch from an early grit shows up.

I have about ten 8″ and 10″ sewn cotton polishing wheels. Each is kept in a 2-gallon Zip-lock baggie with its associated polishing compound. Most are the “sausage” type Gregg describes. I recently bought 1, 4 and 16 micron diamond compounds (wax type) from Ken Schwartz. Not yet entirely enamored of them. Anyway, whether hand-sanding or polishing on a wheel, wherever possible, you use the same direction strategy for polishing out scratches.

For general info, my polisher is a 1HP Jet pedestal machine. I run a 6″ cone-lock drum sander on one end and polishing wheels on the other. I also have a Jet inflatable drum sander 3″ OD X 6″ long, which I mount on the polishing end. The Jet has the stepped long shafts and a variety of spacer sleeves, which works great for the 3″ drum sander. I use the drum sanders for rough work and for shaping knife handles, etc.

Last year I bought a Rikon 6X48 belt sander which also has a 10″ disc. I wish I’d instead gotten the Grizzly 2X72 belt sander, which has a belt on one end and a long shaft for polishing wheels on the other. $495 + shipping. The narrow belt is really a necessity for most blade work.

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