There is a need for a easy to make, functional blast gate system that can easily be put together by members of the DIY community. This system aims to fill such a niche. Before we go on, it’s imperative to note that much of the foundation of this system came from Bob over at I Like to Make Stuff, found here. If you take some time to look at that system, you’ll note there are issues with the gates opening all the way. While the overall system is a great idea, and the code is very well written, it needed some improvement in order to be fully functional.
As you can see, they function highly effectively. So, here’s how to put them together:
Started by cutting out these three shapes. The track piece is just two pieces of 1/4″ baltic birch, glued to a single piece of scrap 1/2 baltic birch.
Took out the old bolt in the blast gate, added a new one with the same thread type, with an extra 1/4″ of length. Notice that the servo motor is approximately half way through the range of motion of the blast gate with the track added. The gate has a total travel of 3.5″. The closer the servo is to the center of this point, the more the motion of the arm will be in the correct plane. Its moving in a circle, so as the arm moves, it loses y axis force, and gains x axis force.
Drill a couple of holes in the top of the blast gate. It’s a fairly soft metal, most bits will eat right through it.
A couple of stainless machine screws were used to bolt through the entire track.
Note how the servo is bolted to the arm. Note the locking nut on the distal aspect of the arm.
The teflon spacer in there is bolted tight enough it stands perpendicular, but loose enough it spins freely. It is the rolling contact point upon which the system articulates.
Below is a final video of two of them in a router table.