Laser Cut Wooden Gearbox

This instructable will show you how to not only design a wooden gearbox, but also cut one out too. Constructing a wooden gearbox like this can be a fascinating and rewarding project for those with an interest in mechanics. And depending on which gears you spin first, it can either make the last one speed up requiring more torque or slow down making it easier to spin.

1. 11.8" long x 11.8" wide x 1/8" thick piece of plywood
2. Muse Titan Laser Cutter
3. Account for fslaser.com
4. Boxes.py

The first thing you must do when creating this is go to Boxes.py. Boxes.py is the website that creates a custom file of your box. When you are making a gearbox, there are lots of settings to play around with such as teeth count on the gears, number of tabs to hold the panels together, and the space between them. Since I wanted to make a gearbox which would spin faster than when it was powered, I made the driven shaft have 30 teeth and the receiving one have 20. But without the tabs on all sides there is no way that the box could have been assembled. The tabs interlock tightly so they can not be pulled apart easily. Because of how tight they are, it is also good to have some space between them so that you don't break it during assembly. But the downside of doing this is that you now have to use wood glue to hold everything together. Or you can do like I did and use bolts as the shafts on the gears to put pressure on the panels and hold them together. With wood glue on the seams and the pressure from the bolts, your box will be very unlikely to fall apart.

Before laser cutting, you must save the file as a .re3. That is the only file this specific laser cutter can read. After this is done you must change the speed and power settings of the laser. This is important because the bed would break down a lot faster if all settings were maxed since the laser would just burn right through everything in it's path and it is very expensive to replace. Also your box would not come out right as it would be burnt and charred black all around the edges and it would not look very good. For cutting 1/8" wood it is recommended to have speed at 100% and power at 70%. When you want to raster an image it is recommended to have the speed at 100% and power at 60%. Rastering means that the laser will engrave a picture onto the surface of your material. Since the power is much lower it will just cut partly through unlike when it is higher it goes all the way through. When removing your pieces, it is very important that you be careful as you could damage some of the thin material.

After you have all the pieces taken out, make sure you inspect them so you know they are good. Sometimes the glue inside of the wood will be thicker in some spots and thinner in others resulting in different results each time. This is why the 3 is much darker than the 1 or 2 on the top panel. But after they are all quality checked and good to go, you can finally start assembling. It is also recommended to use 2 #10 bolts to hold your panels together for max strength. When putting the gears on, make sure you glue each large one with each small one to make 3 sets. There should be one large one and one small one that remained unglued. At the end, there should be a large and a small gear glued together (X3). This will allow the gears to actually power and spin the next one. When actually putting the gears onto the shafts, make sure that the single gears are on top and bottom of the same shaft. Once the gears are glued together, this is what they should look like.