Thread: Finishing hone best value, Coticule or other??

Thanks again for all the great responses I think the 12k is going to be a winner, and for a fun project I think I will make a crox strop next time I am near a fabric store you guys are a great help.

Thanks for the clarification.

Well, it depends…

Pastes are not hones, but if used correctly, in progression, can be and have been used in place of stones, for hundreds of years, to polish a bevel, depending on the paste.

Firstly, though, your results are totally dependent on your stropping skills. A pasted strop is an abrasive strops and it can add keenness and comfort, or if used improperly damage an edge, in one stroke.

The goal of honing, is to first shape the bevels into one flat plane, in the proper bevel angle, (spine to edge) and bring the bevels to meet at the edge, (a fully set bevel). At this point the edge is sharp and will cut hair, though the edge will be ragged and shave uncomfortably, because of the deep stria on the bevel.

The goal then is to straighten the edge, by reducing the height of the stria that terminate at the edge, in a series of ragged chips. The smoother/straighter you can get the edge the more comfortable the shave will be.

Finer stones, produce finer/shallower stria and a straighter edge.

As the edge gets thinner, it also is more susceptible to breakage, (micro chipping) so there is a limit, to how much metal can be remove at the edge with an aggressive stone and maintain a straight edge. That is about .50um/ 30K.

Here is where abrasive paste plays an affective roll, by polishing the bevel and edge, removing a minimal amount of material and still flattening the bevel and straightening the edge.

Chrome Oxide is about .50um about 30K grit equivalent. It can polish a bevel and edge, but result will vary depending on the finish of the bevel and edge at the time. For example, stropping on a 1k edge will have little effect in smoothing an edge for shaving, as opposed to stropping an 8k edge.

The substrate and amount of pressure will also affect results, as will the quality of the Chrome Oxide. For razors, make sure you are using Razor Quality, 100 percent Chromium Oxide, not hardware store or polishing compound. They are not pure Chrome Oxide and contain other abrasives, that can cut quickly and leave a harsh edge.

Chromium Oxide can improve an 8k or 12k edge, smoothing the bevel and edge, but is not the same as honing on a .50um/20-30k stone.

A 12k Naniwa stone is much finer cutting and will leave a shallower stria pattern, than an 8k, stropping with linen and leather it will provide a fine shaving edge. Stropping on Chrome Oxide it will deliver a finer shaving edge.

But, the 12k Naniwa is still or can be an aggressive stone and remove metal quickly, even removing substantial chips, though not recommended for such work. Here is an interesting thread, of doing just that with a Naniwa 12k. (12K Super Stone Chip Removal/Bevel Set).

So, it is not an, either or situation, but the three, 8k, 12k and Chromium Oxide do work well together in progression.

I love my Coti & that I only paid $3.00 for it makes it that much better. I don't have a 12K hone yet but I do have a 10K stone. I do like the Coti edge better than my 10K.
I would go for a 12 K hone in the short term & look for a deal on a Coti. Finish hone under running water with the Coti will make a big difference in the way any Coti works. Hit the antique shops, flea markets & even garage sales & look for all things shaving. That is how I have found ALL of my gear.

Slawman

Originally Posted by Slawman

Hit the antique shops, flea markets & even garage sales & look for all things shaving.

Slawman

That's how I came across my two cotis as well. Both this year - one at a barn sale, one at a flea market. But, they look very different from each other and behave differently so I am still learning them. I agree, always be looking for shaving stuff, ask people you meet and start that conversation, you never know when and where you will find stuff.

Is there a difference where the CrOx is applied?
Leather, linen, balsa wood?

Yes, the hardness of the substrate affects the cutting ability of the grit in the paste, just as does pressure.

So, Balsa will cut more aggressively than leather. Leather and nylon cut about the same, but on leather the paste sits on top of the leather, where in nylon the paste works into the weave and eventually some of the nylon is exposed and does some of the polishing.

I find on razors, I get a better polish if the surface is not completely covered in Chrome Oxide, but that the surface is a combination of paste and substrate, so that the paste, cuts and substrate polishes, much like polishing a car.

Wax on, wax off. I apply Chrome Oxide in ½ in.X 3 in X’s.

Balsa was popular a couple years ago, but new guys were trashing edges with balsa strops, too much pressure.

What you have to remember is a pasted strop is an abrasive strop, and a single stroke can ruin an edge. Watch you pressure.

I have a couple of balsa strops I made when I first got in to straight's & like many others used to much pressure. Stopped that before I damaged anything to bad.My thing with CROX is the CROX I have. I need to get some from SRD as it is high quality & is much better for the blade. Grit size is much more controlled in good CROX. I think I will get the paste.

Slawman

Originally Posted by Euclid440

Well, it depends…

Chromium Oxide can improve an 8k or 12k edge, smoothing the bevel and edge, but is not the same as honing on a .50um/20-30k stone.

Can you expand on that?

Also, does anyone here use the red iron oxide at all?

Iron Oxide and Cerium Oxide both work well for a finer edge, Iron Oxide has been used for many years.

I have use both, for years, good Iron Oxide can be purchased inexpensively from Kremer Pigments. I don’t recall where I bought my Cerium Oxide years ago.

The last few years I have use CBN, in place of both, as you can get it in much finer grits that cut much faster.

A .125 or .25um CBN edge is very comfortable and can be stropped on daily, .125um is about 120K grit equivalent. You can go, as small as .10um/ 160k grit, which for me is too keen.

Yes, it is not just about grit size, Paste, polish and cut microscopically where a hone cuts much more aggressively.

If you use a SG20k/.50um stone to finish, you can still polish it further for comfort, with .50um Chrome Oxide or .50um CBN and get 3 different finishes.

If you do too many laps on the SG20 you can easily thin an edge so much, that the edge will fail and chip. The SG20 is a very aggressive stone.

So as above, even though all three are the same grit size, they will deliver much different finished edges. It’s not just grit size that makes the difference.