Thread: Can I use DMT 220 to lap?

Originally Posted by ecormier

I'm looking at an 8"x3" and I knew it would flatten fast, I'm just concerned about the remaining surface (as has been mentioned) and it's about $100

which DMT are you referencing?

This Coarse DMT is $60
Buy DMT Dia-Sharp, 8" x 3" Bench Stone, Coarse at Woodcraft.com

Originally Posted by rolodave

which DMT are you referencing?

This Coarse DMT is $60
Buy DMT Dia-Sharp, 8" x 3" Bench Stone, Coarse at Woodcraft.com

$60 USD is like $100 CAD. That's the crap I gotta deal with everytime I make a purchase from my brothers to the south.

Yes you have to grid the stone several times and lap in different directions, to get to flat.

I use a kid’s pencil one of those ½ in pencils with very soft lead that leaves a dark thick line, flat carpenter pencils also work well. Mark the stone and do one lap, then look at the stone and see what has been removed, those are the high spots.

I lap from corner to corner then top to bottom. Then re mark the grit, spin the stone 180 degrees and do another lap and look. If you do not do several laps, the slurry alone will remove the grid, but the stone is not flat.

Keep gridding and lapping until the first lap removes all the pencil grid, then smooth the stone face with finer diamond plates or low grit synthetic stone. A progression goes a lot faster, carbide stone also work well for smoothing a stone face.

The CKTG 140 grit, sells for 30 bucks and works very well. It is a thick heavy plate, and pretty flat. I have had mine over a year and done a bunch stones with it.

Originally Posted by ecormier

thanks, but that wasn't the question

I know it wasn't the question!
Mine was more like a suggestion.

No kidding... I won it!!!!

https://www.facebook.com/theclassice...70538622992102

Nice, congrats

I am ammending my statement.

My DMT220 seems to be tearing up my Chosera 1K! Seems to work fine on my Ninawa SS, but leaves all sorts of scratches and roughness on my Chosera!

Going to need to find another way to flatten that one out I suppose... time for another thread, perhaps.

Originally Posted by Aldwyn

I am ammending my statement.

My DMT220 seems to be tearing up my Chosera 1K! Seems to work fine on my Ninawa SS, but leaves all sorts of scratches and roughness on my Chosera!

Going to need to find another way to flatten that one out I suppose... time for another thread, perhaps.

Have you thought about using a moderate pressure at first and then transitioning to "weight of the hone" strokes. I find that using those combined with back and forth strokes especially when finishing leaves a surface with no random scratches or roughness. I never use circles when finishing up lapping, only in the beginning. I use a DMT DIA-FLAT as well so that's an XXC. It leaves no scratches or roughness just a smooth surface, always worth a try. Hope it helps.

Its the plate. I must have hosed a section while working with a pesky W&B (all my W&Bs seem to be a PitA to hone). A new one is on its way... live and learn.

Aldwyn,

In my experience, all the DMT plates need a good break-in. This removes the 'high' spots and 'loose' diamonds from the surface.

I use a block of hardened 1095 steel for this - others have used the shanks of screw-drivers etc.

It doesn't seem to matter what the 'grit' rating is of the plates, they all need the break in.

My extra-extra fine used to leave quite bad scratches on my knives when it was new - scratches that were deeper than the fine plate left.

After a good break-in, all was well. Since then, all new diamond plates I buy get this break-in.

Have fun

Best regards

Russ