There are a number of important buildings in town slated for the chopping block and it’s not uncommon for people to ask for a brick to remember it by. In chatting with some long time Aurorans, they have saved bricks over the years, but when they aren’t properly marked, it’s hard to remember which brick went to which building!
I’ve seen fundraisers where people sponsor bricks for walk ways, and their names are stamped or etched into them. It can be a great fundraiser if you have the space to display them. These types of projects are done with new brick, though, not old. What could we do with brick that we’ve saved?
Enter: the laser. Let’s see what happens when applied to bricks!
I had two sample bricks – one is a paving brick that you could buy at any hardware store, and the second was from the old Aurora Train Station on South Broadway, which was torn down last year. I really did mean for the tester to be done first, because it didn’t have historical value, but the “good” brick from the train station got etched first, whoops! It worked out in our favor and I learned something new about paver bricks.
The Aurora Train Station was built in 1922, and all the bricks were stamped with the manufacturer’s name – “Coffeyville VB&T CO.” During the early 20th century, Coffeyville, Kansas was one of the largest glass and brick manufacturing centers in the nation, and the Coffeyville Vitrified Brick and Tile Company made bricks from 1894-1930. We didn’t want to mess with that bit of history, so we etched it along the edge, which would still be visible if displayed flat. Because brick is a tough material, we etched the material heavily. Raster power was set at 100%, and raster speed at 40%.
Interestingly, the laser didn’t so much etch the brick, but rather, it seemed to melt. The result was a fantastic and unexpected glossy black color. The wording wasn’t as pronounced as we liked after the first pass, so we did a second pass, this time 100% power, 10% speed. This really gave the brick the deep dark shiny black we were looking for.
The first one turned out so beautifully, that I almost didn’t do the paver – we proved it worked, right? And the tester brick’s design was not nearly as well designed – I just put a bunch of typical fonts and some images to test out the capabilities. So it wasn’t going to be pretty or saved for perpetuity. Since I thought it would be a short post, we threw it in anyway. This is when I learned there is a difference between bricks, pavers, and “brick pavers.”
The second etch was not looking the same at all. Instead of black, the etch was turning whiter. Thinking that bricks from a wall and bricks made for paving might have different glazes or treatments, I went to Google for the answer. What I learned: Bricks are made of clay. Pavers can be made of clay…but are more often concrete that’s been colored to look like clay. The name “brick pavers” refers to the shape of the paver, not what it’s composed of. So our paver brick? Concrete.
I DO NOT RECOMMEND PUTTING CONCRETE IN YOUR LASER CUTTER.
As Wikipedia so much more gracefully says it, “Concrete is a composite material composed of water, coarse granular material (the fine and coarse aggregate or filler) embedded in a hard matrix of material (the cement or binder) that fills the space among the aggregate particles and glues them together.[2]” We used the same settings as the second pass on the brick – 100% power, 10% speed. Luckily the concrete DID etch, though it did make brighter sparks than other materials. There didn’t seem to be any smell associated with it, either, so it was probably safe to be in the office with it. What we didn’t notice until the etch was done was the fine white concrete dust that got everywhere. We have a more than adequate exhaust system, but there was enough dust that it damaged the lens. The lens is what focuses your laser for cutting – scratches are no good. Subsequent testing and cleaning shows the lens still does it’s job even with the light scratches around the edge, but it has now moved to the top of the replacement parts list. That price tag is $300, ouch. Do your research kids!
Under the laser, the different parts of the mixture act differently – some specks of black and white are mixed in with the gray. The result was not amazing. I think it would have been more successful if the concrete paver had been more colorful, or even painted. Half tones didn’t really work as you can see from the fire flower, and the text is subtle. I had the brief thought of trying Rub ‘n’ Buff on it, but the materials is all pretty coarse – it would be impossible to rub the excess off. Either way, we will not being doing that again.
In the end, you got a “two-fer” – first time etching brick, first (and last) time etching concrete. Looking at the paver now, of course it’s recognizable as concrete. I feel a little silly for not realizing it from the get-go. It was a mess, with so-so results. Etching the brick, though, was a resounding success!
Check out that awesome gloss!