By machine engraving are you talking about a pantograph? Or do you mean your pulsegraver?
If its the pulsegraver, you can cut with all kinds of things... old files, bed springs, old burs, drill rod, I have tools out of all those and more scrap... but the commercial blanks are pretty convenient.
Ya. I like to see, sometimes I flip a bracelet to sign the back and get a nice inversion of the carving... I use alcohol, but often struggle to get it to release... do you make some sort of vent to get the alcohol in there?
I don’t see a picture.
But if it’s just to test the design, just some plastercine will do you.
If it’s to preserve and immortalized the disigh it will be hot wax.. guessing you make your own.
Drip some sealing wax in heat resis rant container (tin?) and away you go.
If you are going to burnish- burnish in the direction of the scratch. This will neatly close the scratch.
If you burnish across the scratch your approaching stroke may somewhat close the score but the crossing action will open up the other side and you’ll end up with a riffle effect.
Three things that I do for fragile work like that would be some sort of solvent to decouple some of the grease in the lowlands.
Electric toothbrush can get in to places and the opposite motion of the brush
And I often sharpen up wooden tools to get into places with cemented in crud.
With a spring in the handpiece it is meant to receive spurts of air rather than a steady flow.. with a steady flow there will be no reciprocation..
I believe there are other systems (gravemeister?) that operated on a similar principle but with suction,,,
Anyways, from your illustration it...
those lindsay high angl;e gravers will do just what you are asking.. as you see fit you can grind out running away from the cutting edge and you will have all the relief you need for signets and stamps..
there is another way you can look up some Japanese engravers.. the face of their tool...
Lots of trouble over the years specifically (only) with 18kt red gold.
Lots of little things I have heard, and I throughly everything at it and get decent results. Sometimes I get a fracture and make two pieces of plate or wire intead of one.
All said here already, but
Don’t keep the heat...
I use a Lindsay for most of my work, but I will attest that it is not complicated to "tune" the GRS unit.. and once I've got it it is pretty much stable. The Lindsay actually requires more fiddling as you go along, nonetheless I prefer it for most basic engraving.
I'm not sure im contesting...
Your other source would be the suppliers for bronze casting in your city. But bronze is less commonly provided in sheet form. Not sure if the link I put will...
Take what I say with a pound of salt, because I haven't sandblasted engraved work.. I have done some sandblasting preparing large bronze castings for patina and on glass.
Caveat out of the way.
Strikes me, that if you are going to French grey, and your canvas is already level and clean...