Thread: Lapping a surgical black Arkansas

Originally Posted by apvonkanel

I procured a black arky benchstone, and I'm tearing through some 3M 220 wetordry trying to get this thing flat. Any suggestions?

How is this coming along?

My solution is a large extra extra coarse DMT...
not the DMT most ideal for lapping water stones.

Another solution is loose grit on steel or glass.
Common sand and water on a sidewalk can also work
especially if a bit of the sidewalk needs to be scratched down.

If the hone has a big dip to grind away...
In the hardware store you will find big old
carborundum blocks in the cement and tile finishing
section. Called a rubbing stone by some
some are as coarse as 24 grit.

Home depot here has a: QEP Dual Grit Sanding and Rubbing
Stone for Smoothing Rough Edges of Cut Tiles.
One side is 60 grit the other side is 80 grit.

I have seen them much larger from time to time.
The new ones are flat enough

With a good eye you can get the Arky close enough to
finish with less abusive and coarse material.

Good to bevel the corners of other hones once you
get the feel of it.

And yes power tools... like a rented belt sander are
quick. Like any power tool -- be cautious.

I have a large Black Arkansas that is only lapped in the center half of the stone. Now I have purchased a DMT 220 Extra Course, but I hesitate to use it on the Black Ark for fear of wearing it out. I have spent hours on the Black Ark to no avail. This is one hard stone.

I also have a Transluscent Ark that I use with oil. It is fairly flat but I would like to have the Black Ark just as flat or flatter to see which stone is the better finisher.

Any suggestions will be appreciated...........

Jerry
____

Oh there is an option that I used on a mildly translucent stone that did work, and I forgot to mention. Find a nice big area of flat concrete, get a 2 liter bottle of water, wet concrete, get on hands and knees, lap the stone on the concrete using full body weight for as long as you can before you're body gives out...repeat as many times as necessary. When you're done the concrete will be polished too btw. It took me four days of this. Working til exhaustion each time on a new spot of concrete. Good times.

I've been continuing with the 220 sandpaper, making slow progress. I picked up a 60/80 grit rubbing stone that I will use to knock off the rest of this damn belly. I'll report back on its effectiveness.

I agree that arks will eat a DMT, I lost one to arks. Sand paper, Belt sander and old carborundum stones have worked for me. I just received a bunch of loose polishing grits from Got Grit, based on a thread here a month or two ago on lapping stones, with nice photos.

I bought a few Arks & Indian oil stones that need lapping. Harbor Freight sells a set of cheap Diamond stones they are a bit rough, but they are about 12 bucks for 3 and work great for hogging off material, then sand paper then carborundum to finish.

I will post the results of the grit lapping, when I get them out of the TSP. They keep releasing oil. The other thread makes it look promising. Got Grit is a telescope lens grinding site, so they are grinding glass.

Bottom line DMT and Arks… Arks win every time and can get expensive.

Originally Posted by mrsell63

I have a large Black Arkansas that is only lapped in the center half of the stone. Now I have purchased a DMT 220 Extra Course, but I hesitate to use it on the Black Ark for fear of wearing it out. I have spent hours on the Black Ark to no avail. This is one hard stone.

I also have a Transluscent Ark that I use with oil. It is fairly flat but I would like to have the Black Ark just as flat or flatter to see which stone is the better finisher.

Any suggestions will be appreciated...........

Jerry
____

i also bought a dmt 220 for a black ark 10x3x1 it was 10% lappped. i finished it in four hours just let the diamonds do the work after i was done the dmt felt fine but not as corase

Too bad there isn't a place to send Arks off to be lapped. I tried lapping a Washita, and gave up. One of my translucents is 16" long, and one of the Surg Blks is 14", I'm not even going to try those..

Originally Posted by onimaru55

Fastest method I've used is SiC powder slurry on glass. It's also the messiest method I've used. 80 grit is very aggressive & a good starting point but you can get coarser if you think it's needed, then progress to whatever you like to finish on. A belt sander sounds ideal tho if the stone is really dished.
I don't think there's huge risk of embedding grit in a black ark.

And here is another approach:
http://straightrazorpalace.com/advan...one-video.html

Sound advice - cheaper and quicker than a DMT, too.

Regards,
Neil

Originally Posted by eleblu05

to prep a hard or translucent/surgical black i lap them with a 325 dmt(use water) after that i use a 3x1 translucent pocket stone to rub down the stone to smooth it over(use oil ) for the last step i use a steel block(or a knife ) and rub the stone until there is swarf all over the stone(use oil) i repete this three times to get the broken in feel after this process the stone should have a smooth reflective surface and will deliver the best results thats with in your stone ability.

I've wondered if I've got the best surface on my Charnley. Since it's also novaculite, would this treatment translate to it?

Originally Posted by onimaru55

Fastest method I've used is SiC powder slurry on glass. It's also the messiest method I've used. 80 grit is very aggressive & a good starting point but you can get coarser if you think it's needed, then progress to whatever you like to finish on. A belt sander sounds ideal tho if the stone is really dished.
I don't think there's huge risk of embedding grit in a black ark.

And here is another approach:
http://straightrazorpalace.com/advan...one-video.html

With respect to onimaru55, the truly fastest way is to tie it to our back bumper and DRIVE!