Re: Engraving Bricks

Engraving Bricks
Posted by: "Ron Ginger" ronginger@... yaginger
Date: Thu Jan 29, 2009 8:52 am ((PST))

I am working on a fund raising project for the Boothbay Railway Village.
We are looking at a brick walk, where people make a donation and get
their name engraved in a brick.

Ive found a couple sites on the web that do this, for $20 per brick.
Most seem to sandblast them, but one site claims to be 'real engraved'
with special machines.

Id guess a diamond bit in a router on a simple CNC table ought to do the
job. I think Id make the machine a disposable- maybe a wood or mdf
structure. If I got 100 to 200 bricks out of it before it died I would
be ahead of the $20 per brick. I only need a working area of one brick- 4x8"

Has anyone tried this? Any suggestions for a source of bits?

ron ginger

Hi Ron;

[I've drilled regular soft red bricks with a carbide-tipped masonry drill. It didn't have too much trouble getting through the material, but I did notice some chipping of the brick at the edge of the hole. I'm not sure how clean a cut you'd get with a carbide tool, but it would probably engrave at least one brick. The less expensive diamond tools I've used were plated with diamond grit on the surface. They worked pretty well when brand-new, but rapidly shed the diamonds and bogged down considerably. Flood cooling helps prolong their life, but it's still not long. You'd need quite a few to do your 200 bricks. There are new-type endmills that are meant for cutting abrasive materials like graphite; they are carbide with spiral flutes and a diamond film coating which prolongs their life. But they're pretty expensive, and I'm not sure one would last through your whole job.

If I were you, I'd follow the sage advice you've gotten already and do these with an abrasive blasting process. Don't use silica sand, which is dangerous to breathe; aluminum oxide, silicon carbide, or garnet grit work better, and are safer too. If you want to get your CNC skills involved, set up a tangential knife cutter for your spindle and use it to cut the rubber or vinyl mask for the blasting process. Of course, most sign shops have this all set up these days - if you give them the text you want and specify the font, they can produce the stencils for you in vinyl pretty inexpensively.]

Andrew Werby
www.computersculpture.com