I love the term “exhaust blower.” It’s not a flowery name, nor a detailed technical description. It’s blunt. My exhaust blower, a DC-3XL, blows exhaust, and that’s all it does. It does it well, too, and that’s excellent because you cannot run a laser system without the airflow taking your laser-obliterated material out of your work space.

Not that long ago, this mustache pattern covered my window frame, inside and out.

When I acquired our laser system from a previous owner, I inherited their own custom-built window frame to support the exhaust tube and keep the window relatively leak-free while the blower’s installed. It lasted for quite a few years and saw some cute design upgrades (like the mustachioed duct tape shown above), but this summer saw both aggressive weather and aggressive birds who did a proper number on its poor particle-board body.  Wood bowed, tape pecked, and positively filthy, it was time for me to upgrade.

Tools and bits of the old frame. Filthy!

The three interlocking layers. Bolts will hold these tightly together.

The wood originally used was about 3/4″ thick, and I can’t process that kind of thickness in the laser, so I designed three interlocking layers of 1/4″ oak plywood that would seal together with hardware scavenged from the previous window frame. I couldn’t cut the entire length of the wood at once: the window frame needed to be almost 33″ wide and the laser system’s bed is only 24″ wide. I took plenty of measurements to make sure the new frame would fit the window properly, and opted to make two large capital “I” letterforms in place of the smaller pieces of wood that flank the main piece and hold it in place on the window sill.

My temporary exhaust solution while building the new frame.

To solve the issue of birds trying to nest in my exhaust tubing, I replaced the attention-getting mustache pattern with a giant crazy-eyed owl design purchased from a stock vector site. I cut two small rings of highly reflective aluminum-foiled acrylic for the owl’s eyes in the hopes that it would magnify the owl’s bird-scaring properties. I also used a spare plastic drum head to encircle the portion of my window screen that the birds assaulted trying to get at those fancy mustaches. Then, to solve the issue of humidity warping the wood, I sealed each layer with some spray polyurethane.

A closeup of the caffeinated owl before the wood was sealed.

While the “caffeinated owl” design was easy to settle on thanks to its functional purpose, I spent a fair bit of time unsure of what, if anything, to etch into the inside wood.  I like big blocky text, so I took that term I love so much, “exhaust blower” and blew it up in thick, tightly tracked Gotham. For mostly decoration, I also added a warning about using the laser without the blower active, and a goofy label of sorts promoting the new frame’s use of a “Caffeinated Owl Bird Defense System” feature.

The inside face, showing off the faux label etches.

The outer face, sealed and bolted together, ready to install.

The final piece came together with some wrenches, a hammer, and a little bit of elbow grease. It fits very well, and it’s fun to look back now and again and see EXHAUST BLOWER screaming for attention. I wonder, though, how the outside design will fare. Will it properly dissuade birds from flocking to my office? Will it keep the kids living in the town home across the way up at night? I might have to wait until next year to know for sure, but I haven’t heard a tweet so far!

The view from outside. It won’t keep you up at night, will it?