Thread: Charnley Forest?

Originally Posted by Kristian

They aren't smooth on the bottom. That's very uncommon with CFs. Because they are do hard and always hand flattened.

Every CF is old. The last mine closed 90 years ago.

Yes I understand that. They are talking about old as in the time period when they were mined. I guess the ones that came from the earlier quarries were extracted and done in a different way then near the end when they were quarried. So some are more flat on the bottom and sides while others are rounded because of this. Yes some have flat sides and bottoms.

I will a bit corect the presented information.
Green with one layer
Green with more layers which are revealed once the hone is wet.
The round bottom ones are hand cut however there are some flat sided and bottomed which were made in later stages when machinery was more available.
Also after all quarries were closed/disused there was a simgle hone maker who was going arround the area picking up scraps and making hones out of it. perhaps that is reason why the new ones are rarely top quality.
Additionally I am aware of at least two present hone dealers who cuts either huge old hones to smaller ones or got some original material and cut it from it.

which grit of sandpaper you use for lapping CF?. I use a 1k/2k grit

Depends what you want to do. If to flatten then I normally go as low as 40 and then up as much as I want. If to just lap it then most people go about 360 and then use either another CF or piece of steel to burnish it.

Agree to the above. I sand it to 400k and burnish it with steel afterwards

Found this interesting info. I always wondered how they cut these stones and lapped them.

Buy a cookie sheet from the dollar store, sprinkle a tablespoon of 60 or 80 loose Silicone Carbide grit on the sheet, (GotGrit.com) add some water to make a paste, lay the sheet on the floor on the flattest spot you can find, preferably cement.

Use your body weight to grind the stone flat with figure eights, add grit and water as needed. Loose grit cuts much quicker than Wet & Dry. Work up grits to 500, then switch to Wet & Dry, once flat, it goes rather quickly, with a proper progression.

The cookie sheet contains the slurry and mess. Mark a grid on the stone with a Sharpie, pencil will wash off in a few laps.

If I remember correctly some of the early CF stones were stamped or branded "Whittle Hill" on the underside. Mac "McWolf" had one such stone on SRP years ago.
Mike

thank you guys....
Usually I use for my naniwas dmt coarse ...I'm afraid to use it also for the charnley because is very small and thin...but i will follow your advise about 400 sandpaper and piece of steel (what kind you mean?)

As steel people use some old scrap of decent steel such as old screwdriver shank, burnishes or even old chisel used sideways.