Engraving Bricks

[Tim Walters]

Hi All,
I run a small laser-cutting & engraving business just outside of Atlanta, GA. I engrave quite a few clay bricks, and the numbers keep increasing.
My problem is that I can’t seem to get any information on the best way to engrave bricks.
The laser-cutter manufacturers don’t seem to know, and the brick engravers won’t tell me…
I’m running a custom-built 80-watt (RECI tube) machine.
I’ve always engraved bricks by engraving (not the “contour” way.) This seems to give a much better result. The problem is that it’s very slow.
I know I could get a higher-powered laser. Is the engraving speed inversely proportional to power? In other words, if I double my power, can I cut my time in half? Even if I cut my time in half, I’m still looking at quite a while per brick.
I’ve seen videos of galvo-type engravers that use f-theta lenses. Do these work for bricks?
Has anyone tried bricks with a fiber laser?
Any advice or suggestions would be GREATLY appreciated!
Thanks much,
Tim

[Scott Shepherd]

The right way to do any volume of bricks is sandblasting. I've been in your shoes before and it just doesn't work well. Sandblasting gives a superior job. We've done a lot of them over the years. I can't imagine a better way than sandblasting at this point.

[Tim Bateson]

Can't beat Fiber laser on clay bricks. Turns the engraving into a nice molten Black glass.

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[Scott Shepherd]

All the laser engraved bricks I have seen have turned white over time. I had one sitting in our lobby for about 5 years and it was rich black when I sat it there. 5 years later, it was almost all white. It was a clay brick, laser engraved.

[Tim Walters]

Hi Tim Bateson,
Thanks for the info!
A couple of questions...
What speed/power did you use to engrave with the fiber?
What's the wavelength of the laser?
Thanks again!
Tim Walters

[Gary Hair]

Over the years I have experimented with lasering bricks and pavers, clay and concrete, and nothing really worked as well as sandcarving. I've used my GCC 30 watt, Trotec 80 watt, and my 30 watt fiber. The best result was vectoring but that's not practical for anything more than one or two with a very small amount of text or graphics. I have sandcarved thousands of bricks over the years and, for me, the best results came from using Anchor 116 stencil, vector cut letters and graphics, sandcarved, and painted.
If you want to get the best results with lasering then you'll need to go slow with fairly low power, out of focus, and high resolution. The idea is to melt the brick, not ablate it.

P.S. Where in GA are you? I'm in Suwanee.

[Tim Walters]

Over the years I have experimented with lasering bricks and pavers, clay and concrete, and nothing really worked as well as sandcarving. I've used my GCC 30 watt, Trotec 80 watt, and my 30 watt fiber. The best result was vectoring but that's not practical for anything more than one or two with a very small amount of text or graphics. I have sandcarved thousands of bricks over the years and, for me, the best results came from using Anchor 116 stencil, vector cut letters and graphics, sandcarved, and painted.
If you want to get the best results with lasering then you'll need to go slow with fairly low power, out of focus, and high resolution. The idea is to melt the brick, not ablate it.

P.S. Where in GA are you? I'm in Suwanee.

Hi Gary,
I'm back and forth between Alpharetta and Canton.
I do go slow, out of focus, high-res. I do melt instead of ablate. The problem I've seen with the "contour" method is that the brick ablates in the center of the contour.
I (and my customers) are very happy with the results. I'm just not happy with how long it takes to get there.
Where is your shop?
Tim

[Gary Hair]

For speed you need to sandcarve for sure. My office is in Suwanee, Satellite Blvd about a mile from Lawrenceville-Suwanee Rd.

Hi Gary,
I'm back and forth between Alpharetta and Canton.
I do go slow, out of focus, high-res. I do melt instead of ablate. The problem I've seen with the "contour" method is that the brick ablates in the center of the contour.
I (and my customers) are very happy with the results. I'm just not happy with how long it takes to get there.
Where is your shop?
Tim