Why ???

The diamond compound on the ceramic lap is what does the cutting and puts the "mini face" or dub on the tip. If you are using enough pressure to groove a lap you are doing it wrong i'm afraid. You either need to step back up to a courser grit and or let the compound/lap do its job without pushing too hard. The compound does the work not the lap carrying it. HSS is different of course.

Only cause you asked. Think of it this way. The 90 degree dubbed tip is not really a face at all. It's so small you could think of it as a slightly dulled point that can't be seen win the naked eye. And barely under a scope. The actual cutting is done by the face of the tool.
Take out a chefs knife and tap the tip straight down on the counter. Tip is now slightly blunt or dubbed. Now if you cut a watermelon with it what is doing the cutting. The tip or the upper portion of the blade? The tip is below the rind.
Same thing with the dubbed graver. The very tip is well below the surface of the metal being cut.
I suppose if your 80deg tip is large enough then yes it is doing all the work. Very different from a dubbed tip.
Whew. That will be all.
Bottom line if it works then use it.
Oh and James is correct. I dubbed with a ceramic lap for years and there's not a groove to be found on it Not enough pressure applied.

James Ashley said:

The diamond compound on the ceramic lap is what does the cutting and puts the "mini face" or dub on the tip. If you are using enough pressure to groove a lap you are doing it wrong i'm afraid. You either need to step back up to a courser grit and or let the compound/lap do its job without pushing too hard. The compound does the work not the lap carrying it. HSS is different of course.

Click to expand...

I'll have to disagree with you on this. I no longer use diamond compound on my ceramic lap or small ceramic stones, and they can be used to dub the point or sharpen heels on any high speed steel or carbide gravers that I have. So the ceramic does indeed do the work.

Jeff: In 35+ years of sharpening I've never scored or grooved a ceramic lap or stone.

Fair enough Sam:biggrin:
With a brand new ceramic lap carbide has always been terrible for me to try and polish a carbide graver. HSS different story as I said in my comment. Seems strange that ceramic laps are supplied in sharpening packages with diamond spray if its not necessary?:thinking:

Interesting how such a tiny little facet can create such a long dialog...more to come I am sure.

James Ashley said:

Fair enough Sam:biggrin:
With a brand new ceramic lap carbide has always been terrible for me to try and polish a carbide graver. HSS different story as I said in my comment. Seems strange that ceramic laps are supplied in sharpening packages with diamond spray if its not necessary?:thinking:

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I'm not sure who started the diamond spray on ceramic, but I would guess it was Don Glaser. We used it that way for years and there's nothing wrong with it. I remember Chris DeCamillis telling me he got a better polish without diamond spray on a ceramic lap. I tried it and I agreed and never used diamond spray again.

Then Arnaud suggested using diamond powder in place of the spray. Once I tried that I never used the spray for anything including my cast iron lap or leather pad. It just works waaaaaay better than the spray does.

Again, the spray won't hurt anything, but on ceramic it appears not to be necessary. On a cast iron lap diamond powder will polish a graver to a glass-like finish. The cast iron lap was also Chris' idea.

Use whatever works

sam said:

Then Arnaud suggested using diamond powder in place of the spray. Once I tried that I never used the spray for anything including my cast iron lap or leather pad. It just works waaaaaay better than the spray does.

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Sam if you don't mind me asking, where do you get you diamond powder from?
Is is in a paste form when you apply it?
What micron of powder do you use?

Thanks
Mike

Idaho Flint said:

Sam if you don't mind me asking, where do you get you diamond powder from?
Is is in a paste form when you apply it?
What micron of powder do you use?

Thanks
Mike

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It's .5 micron or 50,000 mesh dry diamond powder from eBay. A very tiny amount goes a very long way and it cuts and polishes more efficiently than diamond spray. It's basically the same stuff that's in the spray, but in dry form it deposits heavier and polishes better. Put some on a leather pad as well. Great stuff!!

Ceramic laps, in fact all of the laps that we use - were originally "stolen" from the lapidary trade. I used them myself for faceting and polishing gemstone materials in one of my earlier incarnations.

Lapidaries used (and still do use) diamond and dozens of other abrasives and polishes on ceramic, phenolic, copper, and iron laps. Long before "powered hones" for engravers existed.

Iron laps have been used to polish diamonds a century or two before I was born.


None of these laps were ever "designed" with metal removal in mind... we simply use them because they work well enough to get the job done.

Steve Lindsay will give you a lecture on the subject of grinding and metal removal should you specifically ask.


Brian


In fact, if you go look at lapidary faceting equipment - https://www.google.com/search?q=lap...0QsARqFQoTCIC1tOL--8cCFQc5iAodgOkDtA&dpr=0.95

You will see that engravers "power hones" greatly resemble them and that our sharpening "fixtures" - as well as "templates" - were ALL derived from them.

https://www.youtube.com/watch?v=1_fmqWBBUdk Dr. Wykoff made his faceting templates 25-30 years ago... ?

Those were copied from Brazilian templates far older... and there are examples of templates two centuries old in India and Asia.

Not much of what we use is "new", "invented" or "developed for" engravers.

Just tools that already existed put to a different use.... and sometimes given fancier names. And, of course, higher prices...


The "new" round graver blanks, previously known as drill bit blanks - are another case in point.

One engraver says to the other: "I think the ocean is wet." The other responds "not so much at the edge"

Thank you very much