Lapping natural combo coti

[joshDHM]

Hey all,

I retrieved a nice vintage natural combo bbw/yellow coti.
I think the hone needs some lapping, whenever I put water on it, it just doesnt seem to stay on the hone at all, without any use, it just runs straight off allmost. Also interesting was that the box in which I found the coticule came with a pencil, maybe coincidence or maybe he used the pencil to mark his hone when lapping it.

Ive been doing some research about lapping a natural combo coti,
but I wanted to ask what all of you guys favorable method of lapping would be concerning this stone, I've never lapped a hone so I feel very cautious towards doing this, altho it doesnt seem too dangerous

thank you

another crazy idea, Ive also got a swaty somewhere
what would happen if I'd lap the coticule with the hard swaty o:

[ChrisL]

Dive right in. Coticules were used with water but were also marketed as being usable with oil. The water resistance on the surface you're seeing could be oil residue, lather residue or a layer of greasy age/grime. Once you lap that surface off, it shouldn't repel water like that.

Sure you can at least lap the surfaces clean with your Swaty. You'll probably experience stiction problems which would impair a smooth lapping experience. If you don't have a lapping plate I would buy some wet/dry sandpaper in the 400-600 grit range and a flat surface and work it that way. Not knowing how flat your Swaty is, if you're not overly concerned about getting an extremely flat uniform surface, try the Swaty. I use pieces of barber hones as rubbing stones for my Shaptons, but only on grits up to 4k. I use them to do a quick Nagura type refresh on the Shapton surface without running up to the sink and a lapping plate and also the tinted slurry works well to indicate how an edge is honing on the coarser grits.

Chris L

[joshDHM]

thanks for the helpful comments!

P.S. When the water runs off the hone, are you sure it's on a level surface?

yeah, the hone is perfectly flat

it does seem like chrisl said

The water resistance on the surface you're seeing could be oil residue, lather residue or a layer of greasy age/grime. Once you lap that surface off, it shouldn't repel water like that.

it's like as if you put some sort of oil on your hands and when you try to wash em the water just runs off your hands

[joshDHM]

owkay I had some 3M wet/dry sandpaper lying around, altho the grit was 280.
I just gave it a shot and it worked wonderful, I've uncovered veins in the coti I had never seen before, the surface was bit dirty, it's now less dark and looks pretty nice.
Some questions came to mind, when does one know when you should lap your hone again? Do you just go on your intuition or are there any indicators coming from the hone or blade, etc.
When the coti and bbq are used with slurry or water, the bbw goes from like 8K with water to 4K with slurry , the coti I can't remember;
is there any difference like this when you use it with water or lather or oil

thanks guys

[JimmyHAD]

Whatever you do don't go near that coticule with oil. Depending on how many razors you hone the stone should stay flat for a long time IME. I guess it is sort of an intuition thing and how it feels when you're honing.

[joshDHM]

woops ok, good thing I never tried that and actually never plan on doing so ;p
Not like I'm honing a lot of razors, but anyway, I know what a ''drity'' hone looks like and a cleanly lapped one.
Intuition is awesome.

thanks for the replies

[zib]

Hi, and welcome. I import and sell Coticules, so I've spent a good deal of time lapping them, Natural combo's too. My prefered method is a DMT D8XX followed by a D8C. Normally, the surface is fine after that. If I need to go smoother, I have other Diamond plates, or I use wet/dry sandpaper on a piece of tile. The pencil is used to draw gridlines on the hone itself. As you lapp, the lines will slowly disappear. Once gone, you know your stone is flat. here is a link to a tutorial on our WIKI.

Hone Lapping 101 - Straight Razor Place Wiki

If you run into any problems, Just drop me a PM, I'll be glad to help you...

Rich

P.S. When the water runs off the hone, are you sure it's on a level surface?