Brass Plate Engraving

[Peter Meacham]

So, I had an enquiry about engraving a small memorial brass plate that will be afixed to a cross and set in Wyoming (read severe weather). They would like something that would last a long time.

I don't have an engraver, per se, but I have a CNC. But no engraving bits. I have V-Carving bits.

I have a laser, but I don't think brass will engrave on a laser.

I was thinking about using Durablack - it seems to be rated for outdoor applications (mil spec)

Any suggestions from Creekers on this project please?

[Ross Moshinsky]

Brass will tarnish if put outdoors. It is not rated for outdoors. Can you make it work? Sure but eventually it will fail.

You want bronze.

[Peter Meacham]

Ross - I presume bronze is not laserable, so I would need to get it cast or try engraving with CNC - correct?

[David Fairfield]

I don't think tarnished brass is necessarily a bad thing on an outdoor monument. If the letters are actually engraved into the metal, and the metal is of a substantial thickness, they will remain visible for many many years. I have seen brass spec plates on military equipment left out in the elements for many decades, tarnished but solid and legible.

Lasering into a finish applied to the metal is an unknown. And easy to deface, that's always a concern these days. Since you already have CNC equipment I would recommend investing in engraving bits. Not a big investment in money, and maybe a learning curve to figure out how to do it, but you will gain experience and capability, and that's good for your business. :)

Dave

[Mark Sipes]

This is where a rotary engraver comes in handy. I deep engrave .050 brass plates for our park system for use on park benches. looks and wears great. I also engrave for our memorial cemetery on their cast markers for a unique garden plot. Job it out.

[Mike Null]

I would out source this to somebody like Gemini for a permanent good looking plate.

[Rodne Gold]

If you do a brass plate , use engravers brass - not only can you engrave it with NO lube (its hard unlike normal 1/2 hard "cloggy" brass) , it also weathers to a bronzey colour and does not get the traditional green verdigris that normal brass has.
You can buy engraving tools and do it on the CnC. Use a single fluted "d" bit (actually a V bit) , get Tungsten Carbide. get 3mm or 1/8th if you have the collet , otherwise get whatever shank diameter suits you. When engraving , the ideal is to have as little of the cutter protruding as possible.
As to tip width (the V has a flat tip) the rule of thumb it 1/7th the height of the letters. Try a fairly fast feed rate with a cut depth of less than 1/2 the tip width , vary spindle rpm till it sounds "right" , start in the 8-10k region. Use strong double sided tape to hold the sheet down on a piece of mdf or acrylic spoilboard that you have milled parallel to the head so you get constant depth engraving, use the same cutter to cut the final size out of an slightly oversize piece for a great bevel effect , use multiple passes to get thru thick stuff - 1/2 cutter tip width per pass.
I would definitely try to do this yourself , it might open up new opportunities for you...

[Ross Moshinsky]

Lacquer coated brass is not rated for outdoors. The lacquer wears and leaves a less than desirable finish. Some may like the "weathered" look but weathered turns to haggard pretty quickly in my opinion. If you really cut into the brass and not burnish engrave it, you will have a better long term result but you will still have an ugly piece of brass in about 5 years. I have customers come in with plaques on their walls from 10 years ago and they look awful. Stick it outdoors for a couple of years and it will look even worse.

I'd call up Gemini and have them bronze cast me the plate. It's not that expensive, it's incredibly durable, and people are used to looking at weathered bronze.

[Keith Outten]

Peter,

I would vcarve a piece of Corian and paint fill. You can purchase sample pieces up to about ten inches square, select one of the colors that looks like marble and it will last for fifty years. Another option rather than paint is to mix epoxy with the color of your choice and fill the vcarved area then sand the surface and polish.
.

[David Lavaneri]

So, I had an enquiry about engraving a small memorial brass plate that will be afixed to a cross and set in Wyoming (read severe weather). They would like something that would last a long time. I don't have an engraver, per se, but I have a CNC. But no engraving bits. I have V-Carving bits. I have a laser, but I don't think brass will engrave on a laser. I was thinking about using Durablack - it seems to be rated for outdoor applications (mil spec) Any suggestions from Creekers on this project please? Deep engraved brass is suited to last a lifetime. As has been mentioned, it's the finish that may not endure. In cases where the appearance of a brass or bronze plate is more important than a requirement for a brass or bronze material, you'll find that Rowmark's Metalgraph Plus will allow you to engrave the outdoor-rated, plastic material with your laser, while providing a brass-bronze-like material, that will retain its color over a much longer haul, than metal exposed to the elements. I've replaced a number of brass plates with Metalgraph Plus. One way to fool the untrained eye (and even some trained eyes) is to enamel-fill the engraving, even if the core color is black.