You can take a look at this link,people have been diamond charging copper laps for many years without problems .....https://usfacetersguild.org/using-copper-laps-to-cut-with-diamond/
Tool https://kingsleynorth.com/recharge-roller.html
My wife said the same thing when I used a belt sander in the basement on a cow horn when making a powder horn.The smell like burning hair was not appreciated in the house.
The material is nothing special,have none of you ever used a pitch bowl to hold your metal "plates" to be engraved? The material had been used for centuries,the recipes above are basically chasers pitch.... https://www.northwestpitchworks.com/
This one? https://www.bladesmithsforum.com/index.php?/topic/24166-simple-engraving-for-knifemakers/&tab=comments#comment-227557
Examples of Tom's work ............ http://sterlingsculptures.com/wp/?page_id=507
Dop wax available at most lapidary suppliers............ https://cabking.com/products/green-dop-wax-1-4lb
https://www.sierragems.net/proddetail.asp?prod=DOPWX-1
The steel usually used is mild steel(1018). Softer metals can be used but the "teeth" produced to hold the overlay can be smashed do to the softness of silver,copper and brass. Take a look at my final project photo above,it was done on Shakudo, a copper and gold alloy with 4 to 8 percent gold.
See link in post#11,a hardened scrapper,and burnishing tool. Those who used a steel base then used the Urushi Lacquer as a coating. burnisher.... https://www.momokoya.com/product-page/burnisher-%C3%B83-5mm
My final project was done on Shakudo.
The chisel is held at around a 60 degree angle and the cuts are diagonal,vertical and horizontal with a count of 16 per millimeter. The Higo inlay uses a thicker metal than most of the other Zogan Nunome in most of Japan. We did not use antler,we used a piece of bamboo chopstick with the end...
The technique has been used on firearms for centuries,if it wasn't durable I doubt anyone would be using it. Maybe the "Western" term of Damascene would be more recognizable. I attended a 5 day class at Revere Academy Masters Symposium for Zogan Inlay a number of years ago.Two days of lectures...
The 117F isn't too hot,just put your hand in cold water for 30 seconds then put your hand into the pot of melted alloy and pull it out with a metal coated hand.