Laser Cut Cornhole Set
It's somewhat of a rarity to have a backyard in San Francisco; let alone one large enough to play lawn games on. Alexa and I decided to collaborate on a cornhole set for the yard. She'd take care of the art and design aspects. I'd do the engineering and fabrication. In addition to playing it on the lawn, we wanted this corn hole set for beach days. Due to the size of a standard cornhole board, we needed the boards to be portable (easy break down and flat pack) and of a lightweight construction.
Required Resources: 6 hours, $30
Size: 24" x 48" x 12"
Materials: 3/4" Plywood
Finish: 3 x Coats Spar Polyurethane
Tools: Laser Cutter, Orbital Sander
New techniques: Flat Pack Cornhole
Design
Conceptual and CAD design with the goal of an easily assemble-able and light weight design.
I've done a fair amount of of "mortise and tenon" lasered box design in the past, so this cornhole was right in my wheel house. A total of 5 piece construction assembled with press fit joints.
Orthographic projection of the cornhole design. Notice the "Crewvier" inscription. We lived on Cuvier street. A ha, a pun. Ok, maybe not that clever.
A portion of the layout for the laser cutter . We bought one 4' x 8' sheet of plywood and had to be exceptionally space efficient with the layout. The laser made quick work of the 0.75" ply; cutting without any charring nor having the wood catch on fire. Kind of a miracle, honestly.
The Build
Assembly, sanding and finishing the cornhole boards.
After Alexa's art (a stylized owl and whale) were etched on to the boards, I assembled the pieces and sanded flat any protrusions.. Easy! And with that, the bulk of the mechanicals were done.
Alexa and I finished the boards with 3 coats of Spar Polyurethane, an outdoor, UV resistant varietal of poly. After painting the poly on for the last coat, we had to sand the surface to ensure evenness /flatness of the playing surface. We then stepped up the grit number (higher number = finer grit) on the sanding discs until we achieved the right surface finish (and thus coefficient of friction) for game play.
Lessons Learned:
The Dangers of Living Outside: Woodworking pieces that stay outside need maintenance. UV from sunlight causes degradation and flaking of the polyurethane coat and bleaching of the wood. With a compromised poly coat, moisture can seeps into the piece and cause mold, or cause delamination of ply wood. These cornhole boards survived the first year in our backyard well, but were in desperate need of another coat of poly. We touched up the degraded sections and the boards looked solid for another 6 months. We've now neglected their upkeep for the last 8 months and they are starting to look worse for the wear. The plywood is splintering and mold is starting to form in well worn areas of the board. We'll probably sand them down soon, but each sanding makes the etchings more faint. I think the key to longevity for a project such as this is to either take the boards indoors after every use, or to be diligent about reapplying spar poly every 6 months.