Polishing compounds

Stacy E. Apelt - Bladesmith

Stacy E. Apelt - Bladesmith

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All the polishing kits are gone, so this is not a promotional thread.

I have had several folks ask about the use of different polishes.

I decided to post this thread to give my thoughts, and encourage those who USE polishes to give their experience. Those who have read about polishes ,feel free to ask questions and post about things you heard/read, but let the guys who do it regularly post about what works and what doesn't. Lately we have had a lot of advise from folks doing their third knife, or so, as to how to do things. Sometimes that is fine, but for topics like buffing and polishing it takes years to get the proper experience to give good advise to others.
OK, rant over.


SAFETY - THE BUFFER IS DANGEROUS - IT WILL HURT YOU IF YOU DON'T RESPECT ALL THE RULES.
Buffers running too fast, having the wrong wheels, buffing with an edge up, not paying full attention, being in a hurry, and the most stupid of all - buffing from the back with the wheel turning up and away from you.....all will get you cut or worse. Buffer cuts are rarely a nick..they remove pieces of your hand in less than one second. Buffers can kill or severely injure you.

OK, now that we have chases all the kids and wives away.

The easiest way to get polishes straight in your head is to think of them by color. Black is the coarsest and white is the finest.
The rouges in the kits were:
Black - similar to fine emery. Good for taking out the final scratches and working up a matte lustre.
Yellow - medium abrasive good for getting a nice polish. Works good on brass/nickel,too.
Tan tripoli. There may be two colors. The darker is just a bit more aggressive than the lighter one. This is a polish that can get the blade ready for a final polishing.
White Diamond tripoli - For a high polish on blades, as well as buffing handles and ivory.
The rouges - red,green, yellow, white - are all for a final super bright polish. There is a slight difference between them, but they all do great.
Red is the classic rouge, and works very good on steel as well as softer metals like brass and nickel.
Green is best for stainless steel.
Yellow is wonderful for buffing and stropping the edges after sharpening. It also works great on most everything as a final polish.
The white is for ivory, and wooden handles. It will take any metal to a mirror polish, too.

The Linde A powder is for charging strops and polishing by hand.
Oil a leather strop and rub in some powder. It will strop the edge to a perfect smoothness.
For hand polishing things that you can't buff, moisten a soft cloth with baby oil ( smells better than WD-40) and work in some powder. Buff by hand. Keep the cloth in a zip-lock bag for re-use. To buff ivory by hand ( especially good for carved handles) use water to dampen the cloth.
You can also make a slurry of the powder and oil and use a small felt pad and a wooden stick to polish in sculpted areas, and plunge lines ,on a blade. Use the same method you used with sandpaper to get the area smooth in sanding.

Finally, the rouges as well as Linde A are also is good for doing final togi on Japanese blades. They work well for those who do a Hybrid polish. You can make some powder by scraping them on a spice/nutmeg grater. DON'T USE SANDPAPER - it may get grit in your rouge powder and cause untold heartache. A small 1" square felt pad and your fingertip works great for brightening/darkening along the hamon.

There are many colors and types of polish, with the actual abrasive being nearly the same in most, and the binder type varied. The color is almost always just an added dye. In buying polishes, do your homework and see how much the particle size varies. Some "Cheap" polish has a lot of larger grit allowed to get in with the finer polish...which is not a good thing. Many of the "fast" polishes are done this way to cut quickly. The finish under magnification is a lot of polished scratches, not a smooth surface.

Green polish can be one of two things. Green Chrome polish or Green rouge. Chrome polish is superb for stainless steel and it contains chromium oxide. Green rouge is a fine grit rouge made with iron oxide and dye. Some high quality green rouges have both Chrome and Iron in the mix. Green Buffing compound is usually aluminum oxide that is dyed to look like its more expensive ( and better) cousins. So if it is green, look for the words "Chrome" or "Rouge". A check on the MSDS or grit analysis is how to find out the content in polishes. Also, look at the percentage of binder/carrier to polish. Some cheap polish is mostly clay and wax.
 
Stacy
I have a hard time with buffing and grinder belts.
A few questions and thanks for doing this.

1- What is the difference if any between buffing and polishing?
2- What type wheel should I use with each.
 
Thanks for posting this, Stacy. You left out one (or I missed it) - the pink scratchless compound. I use this a lot to get the final overall polish on more than just my knives, after I'm done with the white rouge (I've only made a few, so I won't post any "advice").
 
Great thread, Stacy. Which rpm's would be best for polishing? I have always assumed you slow down the rpm for the finer grades, is that correct? Also, after which grit of sanding does one start polishing, 800, 1000, higher?


-Xander
 
Sorry, I was typing a reply and we had an earthquake and I had to clean stuff up....Internet is back up now.

No scratch pink is a fine white diamond tripoli with a touch of pink dye from what I can tell. It is good polish for final polishing and on handles. It does not appear to have any tallow, so it wipes off easily.

I prefer to buff at 1100RPM and 700RPM. 3450RPM buffers are foolish in my opinion. 1750RPM is OK, but faster than I like for knives.
No need to slow down for the final polish.

Use good quality treated muslin wheels for all but the final polish. Use unstitched linen for the last polish. 10" wheels are best, but any size above 6" will work. The bigger the safer , as you have more wheel below the knife. Also a larger wheel can turn slower and still have the same SFPM as a smaller wheel at higher speeds.

There are many types of structured wheels that can be used for blending and smoothing, but they are not a beginners product. In the right hands, a charged blending wheel can take 120 grit sanding to pre-polish. Obviously this only works on full flat and convex grinds.

For most people - sand to the finest grit available before polishing. At least 1000 for a bright finish. 2500 for a mirror polish.

On that subject, I will say that I don't like or use a mirror polish.At most, I use an etch and light buff, or a scotch brite belt and light buff. Few of the knives I make are super shiny. I think a 400 grit finish is attractive and durable on a user.
 
Bump: I'd sure like to hear more about grit and color progression.
After watching Loveless's video on knifemaking, I tried green chrome and I'm very impressed, but not quite sure where it fits into the polishing progression- if I remember right, he went to chrome after about 400.
I've used it on O1 and thought it did a nice job, is it usually used only on stainless?
I just picked up some black yesterday and can't wait to try it.
Andy G.
 
I have used dark grey as my local supply house was out of black and they said it was the same but it was not, Stacy can you tell us what this rouge is and where it falls in the line up?

Thanks
 
In general, the color and grit progression is:
Black (100-200 grit emery in wax/tallow/clay mix)
yellow ( 200 grit area ungraded coarse rouge and tin oxide in above carrier)
gray ( 220-400 grit SC with some sort of blending compound of other abrasives . Amount of carrier varies. Comes in light/medium/dark = 400/300/200 grit.)
red (800-5000 grit rouge mix - iron oxide , less carrier)
tan/brown ( SC and Alumina mix like gray, but finer - often called Tripoli, Blending or Bobbing compound. High tallow content carrier.)
green ( 600-3000 grit Chrome oxide mix in light carrier.)
white (600-1500 grit fine tin/alumina oxides. Carefully graded and with little or no carrier.)
Matchless white and No Scratch Pink ( closely graded 1500-3000 grit, no carrier. BTW., Matchless is the name of the company that makes the polish.)

Use black yellow brown and tan for blending. Use red and green for bringing up the polish. Use pink white for final polishing.
 
Thank you very much for the post Stacy. I had been trying to figure out what compounds I need. This thread cleared it up for me.
 
Stacy,
Thanks for putting this together. Hopefully I'll need this advise sooner rather than later.

bladsmth said:
.....
Use good quality treated muslin wheels for all but the final polish. Use unstitched linen for the last polish. 10" wheels are best, but any size above 6" will work. The bigger the safer , as you have more wheel below the knife. Also a larger wheel can turn slower and still have the same SFPM as a smaller wheel at higher speeds.
.....
Click to expand...

So what makes a buffer wheel a quality one? When I hear the name harbor freight, I automatically think sub par items. Could HF mess up something like a cloth wheel? If they can be found at places like home depot and lowes, are they usually any good? What needs to be looked at to see a quality wheel?
Thanks,
Rob
 
If I may ask: what I don't understand is what the difference is between some compunds.
Some are sold as compuond for bone/wood/horn and others for CU-alloys and special ones for steel and stainless
If the only difference is gritt size, is it marketing trying to sell three bars?
 
There are so many formulation differences as well as what abrasive works best on what metal.

Some metals polish by smearing the metal until it is smooth. Other metals polish by abrading the surface until it has finer and finer scratch marks. Different carrier compounds will either lubricate the abrasive or allow it to come off the bar as loose grit.

The ones that are for copper,silver,brass, nickel,gold are often called colouring ( coloring) compounds. The ones with fine loose grit are called polishing compounds.

Most polishing starts with a coarse compound called a cutting compound. This has sharp larger grit mixed with some finer grit in a lubricating carrier. Black and gray are the normal starts.

Ned step is taking all the tiny scratches from the grinding and cutting polish and making them smoother. This is called the blending polish or medium cut. Tripoli, brown/tan and bobbing compound are these types.

Carbon steel colours when polished, and will polish with most fine compounds, rouge being a good one. Stainless requires a medium polish first with what is usually called a blending compound, and then a final polish with green chrome or diamond white. If you try to polish stainless with a colouring polish, it will have a cloudy finish that you can't seem to polish away.

If a super high lustre is desired, a final polish with a very fine and loose type grit compound ( no carrier) is done. No Scratch Pink, and Matchless White work in most cases. There is a Super Green for stainless. Use a soft combed linen wheel for this and polish gently.


Wheels:
Most any wheel will work. Quality usually determines how long it will work. Treated muslin wheels will last longer than untreated. Stitched wheels are stiffer and last longer than unstitched. Coarseness runs Sisal-Canvas-Muslin-Cotton-Linen.
Where the quality really shows in in the finishing wheels. Good wheels will, be rounder and have better centers.
Try what is available cheaply and compare it to what the knife supply sellers carry.

The knife supplier won't carry a product that won't work. They also have done the reading and study to know which polish does what, and which wheel works on steel best. Read the catalogs and web sites and you will get an idea of what you need for your shop. No one needs twenty polishes ( well, almost nobody). Four polishes will suffice most small shops. A starter kit is Black Brown White Green. I would suggest that you buy your first wheels and polish from a supplier like Pop's, who was a maker. Then you have a good baseline to compare other sources with. In my experience, it is hard to beat Pop's prices and quality for grinding and polishing supplies. He uses them himself, and gets feedback from thousands of makers. There is no one between you and him...so he has to be right on the spot or he will be out of business. All you have to do s ask James (Pop's) and he will be glad to advise you in what you need. One really big plus is that he won't sell you something you don't really need. I have heard him say to a customer , "Yeah, I know a lot of the guys use/do/sell that, but all you really need is....."
 
Maybe this should be a sticky? Great info, I haven't been able to find in my searches, maybe it was there but not put together in a way I could understand.

I'm wondering about hard felt wheels, could they be used in the same way paper wheels are for sharpening and have other uses also?
 
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