Thread: Pasted edge refinished on a stone

I have been chewing on this one for a while,

I was reading an article on the science of sharp blog a while ago and it was about using metal polish as an abrasive strop compound. Which by the way works exceptionally well despite all the criticism it receives. So here's what I have been playing with when taking a break from the shapton glass. This works very well with a one stone method on a coticule.

I have been setting the bevel at 1 or 3k. Really not important. I would then take the razor's edge as far as I can go on the coticule using a milky slurry and diluting to plain water. Some hones I can get right to shave ready and others fall short which is due to any number of things, including grind of the razor, coticule in question, coticule speed on slurry, how refined the edge will get on water etc. etc.

So not wanting to add a layer of tape to the blades I decided I would give this metal polish a go. Put some on a linen strop and rubbed it in. Then I would proceed to 30 laps on the pasted linen. The edges were ridiculously sharp. Tree topping leg hairs with ease and passing the HHT with flying colours if you use that test. If you've got it calibrated bravo, if you haven't and think the HHT is for idiots. Nobody cares. Especially not the guys who successfully use it as "part" of their sharpness tests and use it before a shave test.

So wanting that nice gentle coticule edge I would refinish the edge on my coticule with water. Which retains the sharpness of the edge but smooths out any microchips that the paste would cause. Resulting in uberkeen, smooth edges that shave without irritating the skin which in my world with sensitive skin is a top priority.

My question is what happens when you refinish or transition from a pasted edge to an edge from a hone? Are you reaching the edge or just straightening out the convexity you just introduced?

Whatever the case it is a pretty bullet proof way to hone a razor on a coticule if the stone you've got is giving you problems and it keeps that extra layer of tape off.

- Scott

I've been wanting to try that since I've sliced my fingers when polishing a dull razor with just mothers polish and a rag. The polish would sharpen it enough to cut through the rag and my fingers with ease quite fast. I learned real quick to be more careful when polishing.

Not being familiar with the technique used, I revisited the Science Of Sharp site to gain a perspective with the process. In short, it goes something like this (1) Set the bevel on your 1k and finish with 20 edge trailing laps. (2) Using a hone from 4k to 8k refine the bevel and again finish with 20 edge trailing laps. (3) Remove any foil-burr and to induce convexity at the apex with a denim strop pasted with metal polish (I think Mothers and Fitz were mentioned) about 30 laps. (4) Clean up the apex and impart keeness by stropping 30 laps on hanging leather pasted with .25 micron poly-diamond spray. and finally strop as usual fabric/leather.

If this is the technique of which you speak, I would think that using a coti afterwards would eliminate all the geometry and convexity imparted by the previous process. The edge you shave with would be a coti edge not a metal polish and diamond spray edge. That being said,I may scrounge up a old blade and give the process a test. After all you can not condem what you have not tried personally.

I have been playing with going to the Coticule after the paste and what I really enjoy about it is that water only laps do not seem to reduce the keenness noticeably. It does however make the edge much smoother. I have not worked out all the kinks yet but as for repeatability I seem to be getting pretty darn good at it. I was searching for techniques I could recommend a new guy starting out with just a coticule as his only hone. I know Lynn always praises experimentation and having fun and this method is a lot of fun because I'm very sure the technique described would also work with various other pastes that I do not own or will not purchase. I also stop his process short and do not go to the .25 poly diamond. I don't own it and I do not feel the need to as I am finishing on something else and not finishing on the pastes. I am bridging a keenness gap left after unsuccessfully utilizing a one stone honing method from a milky slurry to straight water. Allowing one to gain an exceptionally keen (coticule) edge without the figuring out the finicky intricacies of his coticule.

Please do try. I would like to know how it works for you Wirm.

Scott

Pastes have been used in progression, for hundreds of years in place of stone honing, most popularly in Europe. All that you are doing is using the pastes, (Metal Polish) as your mid grit hones.

In regular, (missionary) honing, we set the bevel on a low grit stone in the 800-4Kish range, then progressively, polish out the bevel setting stria and each subsequent grit’s stria, until we get to the finish grit, 8,12, or 20K.

One stone honing does the same thing except you go from bevel set to finish, with the same stone, thinning the slurry and skipping a lot of laps in between.

I have experimented for years, setting a bevel on a 1k, then strop on a metal polish, polyester canvas strop. About 100 laps will remove all the 1k stria, the edge can get a little ragged, depending on the steel.

This works well with hard razors, where chipping is less.

The brand of metal polish does not matter much, they all work about the same, some are a bit more aggressive than others. Experiment by pasting the inside of a cereal box cardboard with 3 inch X’s and holding the cardboard, on the edge of the bench or glue it to a board.

You will now have a stria less bevel, (at least visible to100X), with an edge, that is pretty straight and maybe a little chippy, because the girt in most metal polish, is aggressive Aluminum Oxide or similar girt of unknown size.

Now on a fine finish stone, 8 or 12k, even a 20k, (or Coticule), joint the edge straight, as many strokes, as it takes (probably not more than 2-3), and re-set the bevel on the finisher, 8,12, or 20K, it should not take many laps, 10-15. Jointing will give you back a straight edge lost to the metal paste.

You now have whatever finishing stone you used, 8,12 or 20K, Coticule edge. Now strop on Chrome Oxide or CBN and shave.

The edge is no different, than if you went through a full 4 or 6 stone progression and ended where you ended.

The trick is, you have to have your stropping down, or one stroke can wipe the edge, if it does reset it and strop out the stria.

Yes, stopping does convex an edge, but not like most folks think, we are talking microns. A high grit finish stone will quickly remove the convexness made from a pasted strop and you will have a flat bevel, all the way to the edge.

I know some people with Jnats do this. They finish with their stone, strop on CrOx, then go back to their JNat for 6-8 xtremely light laps, and finally strop on plain leather or horse butt

The goal of honing a razor, is to first set the bevel, flat, at the proper angle, and bring them to meet in a straight line, the edge.

Then using, progressively smaller grit stones, to leave smaller stria on the bevel and a straighter edge. The smaller/shallow the stria, the straighter the edge.

At 8k your edge begins to get very straight, because of the small grit stria on the bevel. At 12k most if not all the stria is removed and the edge is super straight. At 20k the bevels are polished and the edge, laser straight.

So, if you set the bevel with a 1k, then polish away all the stria on the bevel with metal polish, you don’t need all the middle stones and can just re-set the bevel with a finish stone, in 10-15 laps.

By polishing the bevels, you just eliminated all the middle grit stones,

Yup, it works.

If you want to experiment, paste a piece of cardboard, (inside of a cereal box), with finger painted, 3 inch X’s. Hold the cardboard on the edge of a counter and do 100 or so laps, don’t be afraid to use pressure.

Some hard razors, like the Chinese, and Hart, actually like the polish and you will get very little chipping, especially if after the bevel is fully set, you joint the edge, on the 1k and get it as straight as possible, using lite pressure laps to reset it, then polish.

I've done similar with decent results but I only went back as far as the CH12K, not to my coticule.