Lapping advice for Translucent Arkansas?

[bernie01]

You don’t want to scuff up, or worse, dish out a polished counter top.

It's NOT my actual kitchen counter, it's an OFFCUT about 18" square that I got from friends when they were renovating their kitchen. I've confirmed it's granite. It's polished, so I will be able to see if it is wearing pretty quickly. But I guess I can source a cookie tray to go on top of it.

 

[Christian1212]

What I like to do is float glass with sandpaper on top. (If a lot of lapping needed I will use sic powder on top of the sandpaper). Have not lapped that many arks though

 

[Legion]

What I like to do is float glass with sandpaper on top. (If a lot of lapping needed I will use sic powder on top of the sandpaper). Have not lapped that many arks though

I just use float glass with the SIC directly on top. When the glass starts to dish I chuck it and get another piece.

 

[Mr Kooby Shemayrew]

It's NOT my actual kitchen counter, it's an OFFCUT about 18" square that I got from friends when they were renovating their kitchen. I've confirmed it's granite. It's polished, so I will be able to see if it is wearing pretty quickly. But I guess I can source a cookie tray to go on top of it.

Oh, in that case….. have at it. Just use a large pattern so that if it wears, the wear pattern is large enough to provide a flat area. That’s what I do. I haven’t tried it but a cookie sheet sounds like a good idea.

 

[psfred]

I recommend a cookie sheet, that grit will track all over if you are not careful, and scratch all sorts of things. Including razors if you manage to get it on a finer stone, too!

 

[duke762]

I haven't tried a cookie sheet yet, and I'm sure they help contain the mess.....but...I'm more than a little skeptical of how flat the cookie sheet is and keep in mind, it's pushing back at you, anywhere it's not flat.

Mess is a consideration. When I lap Arks on plate steel with silica sand, the sand is guaranteed to fly at least 3 feet in every direction. I get sand all over me and the entire work area where I do this. That is why I do it at work, in the bowels of hell where no one will notice the mess. Well, actually they do and cry about it so I clean up the area the best I can. A little discretion goes a long way in maintaining harmony......

 

[bernie01]

...but...I'm more than a little skeptical of how flat the cookie sheet is and keep in mind, it's pushing back at you, anywhere it's not flat.

Yeah @duke672 , I've been assembling the various bits required for this project and on Sunday purchased a 3 piece set of cookie sheets from K-Mart. Looking at them, I had the same thought as they are fairly flimsy. I thought from a mess containment point of view they might be advantageous but how are they conducive to flatness? I had pretty much decided to do the lapping outdoors (it's summer here in Australia) and maybe use the cookie sheet on top of the very flat granite cooktop offcut that I have. I think you raise a very valid point; will see how this turns out in practice. Thanks for the input.

 

[Legion]

Yeah @duke672 , I've been assembling the various bits required for this project and on Sunday purchased a 3 piece set of cookie sheets from K-Mart. Looking at them, I had the same thought as they are fairly flimsy. I thought from a mess containment point of view they might be advantageous but how are they conducive to flatness? I had pretty much decided to do the lapping outdoors (it's summer here in Australia) and maybe use the cookie sheet on top of the very flat granite cooktop offcut that I have. I think you raise a very valid point; will see how this turns out in practice. Thanks for the input.

I do it in the shed on glass sitting on an old table. The mess is not so bad, and when I need to I just walk a few steps into the yard and hose the old SIC off the glass (do not wash it down the sink, it will eventually clog the U bend.)

The only real consideration is a few particles of SIC will probably eventually get under the glass and scratch the table, so don't use a table that you care about the finish on.

 

[psfred]

The grit doesn't wear the steel anywhere near as fast as the stone. What counts is how flat what the sheet is on. It will wear, but if you cover a large area as you lap it will stay pretty flat.

Don't try this on marble....

 

[bernie01]

Finally got around to lapping this translucent ark; thanks to all for the useful advice. As I am 6'4" I had trouble finding a bench at the right height but eventually hit on the idea of using an ironing board as a taller base. An offcut of granite on top of that, then a cooky tray. I've finished both sides with 60/120/240/400 W&D and SiC, then finally 600 W&D only. After a few shaves I will consider going to 1000 or 1200 on one side. Looking forward to shave with an edge off it soon!