Thread: Charnley Forest hone lapping question

Surely !!!

I've polished the surface with wet sandpaper ( 400, then 1200 ) then rubbed the coticule slurry stone approx. 5 minutes, then washed the Charnley with brush to clean out all of the coticule slurry ....the surface of the hone became very-very fine similar to the translucent arkansas hone. After lunch I m going to search for a wide chisel

Do yourself a favor, and run the chisel across some emery cloth or some other stone first. If you have any high spots or burrs on the chisel you will just grind a new scratch into the Charnley! (trust me on this one!)

Yes, good call, thought that was obvious so didn't think to mention it. Definitely use a coarser stone to form the chisel into a convex bevel first or at least get it to a reasonable facsimile of flatness.

You can also use a large floor tile for flatness with sandpaper.

Originally Posted by engine46

You can also use a large floor tile for flatness with sandpaper.

This is how I would go & have gone, with a progression of wet/dry sandpaper to as high as you can get in your area. I like to visit automotive parts stores for my sandpaper. Your CF should be as smooth as you can get it.

You can lay the back of a chisel flat and get the same effect (vs. using the bevel). There is less risk that way. Any $5 hardware store chisel will work fine, as would a hardened large knife (but one of good quality probably wouldn't come as cheaply as a chisel, and may not be quite as hard).

Grading the surface with the flat back of the chisel also does more to keep the surface flat (and is what a woodworker does when using novaculite stones to keep them flat, after working a bevel).

Dave, even a new chisel, on its flat back, may turn out to have a raised edge which will bite into a stone. again, "Trust me on this" <---me after 3 hours of hand flattening a dished CF only to put a new deep scratch with a chisel back

You can stone the edges on those chisels pretty easily. As a woodworker, and knowing that charns aren't as hard as trans and black arks, I wouldn't want to do much bevel work into those stones, even dragging a bevel will allow a corner of the bevel to scratch the stone.

I guess also as a woodworker, it's easier to do when you already have some dead flat chisels in current use.

When I want to condition a stone, I grade it with another similar stone and then use a mineral oil and a chisel or plane iron - mineral oil only because water and thinner fluids don't always get the particles out that well, but oil floats most of them out.

Having a similar stone around is a bit of a luxury, I guess, but anything even close will work well (e.g., grading a hard ark or charn with a soft ark).

All the methods described work well.

I use lose 60 or 80 grit Silicone carbide in a large cookie sheet with soapy water on a flat-ish piece of concrete. It will get you to reasonably flat much quicker than paper. Rotate the stone 180 degrees a couple of times remarking the grid.

Use a felt marker instead of a pencil to mark a grid on the stone. Pencil will wash off in the first couple of strokes.

Once flat, use a marble or granite tile or piece of counter top to smooth the face, I picked up a large piece of granite counter top from Habitat for Humanity for a couple of bucks.

Tile or counter top and wet and dry paper with soapy water will get to smooth fairly quickly, the higher the grit the better. A large Carbide stone works well also, and can be picked up for a couple of dollars.

Burnishing with flat carbon steel will better prepare the stone face and works for all hard stones, like the Chinese stones. I use an old heavy carbon steel cleaver with pressures.

Water and Smith’s honing solution works well, but on some stones mineral oil seems to work a bit better on a really hard stone. Once your stone is clean oil can be washed off with a good degreaser, like Simple Green.

If not it will turn rancid.

I've completed the process with the wide chisel...it was a very good advice, the "chisel trick" works very well, now the charnley works brilliant, and the surface is very very fine....got the sharpest edge after approx. 50 laps on the charnley with oil and about 50 laps on my Ozuku jnat very light slurry......thanks again to everybody !!!