A little backstory. I really wanted to design pistol grip but could not come up with anything unique, so I wasn’t planning to build one of these. I thought the form factor of the PCB with the thumb wheel lead to only one direction for a pistol grip. @Redeye and @glyphiks seem to be already heading down that path so there wasn’t much to add there.
After looking at the board for a while, I just wanted to cut the trigger off the board so it could be moved to new location. This is probably cheating, but I don’t really care cause it ends up being a pretty good remote.
Edit: Because of the modification of the Hoyt PCB , I purposely did not add [Puck Design Contest Entry] and throw my hat into the ring. I still want to share this without all that anyway.
Anyway, It turns out there are too many traces in the vicinity of the rotary position sensor, so cutting the board is a no go. I decided to just make my own PCB and wire it to the main PCB (with the sensor moved). Below is the prototype of the board and the whole trigger assembly that can be remote mounted. I used copper cladded PCB material and an exacto knife to score and peal the copper into pad. I put in the mounting holes for the bracket and sensor with a bridgeport, since these need to accurate. After that I just trimmed the board to the smallest size matching the bracket.
After testing this, I knew this was a good direction so I decided to order some cheap, quick turn PCBs with this design. I am getting 20 boards next week so I will have extra. I will send them to those of you that want to make a remote with the trigger separated from the main PCB.
This is the model of the trigger assembly. The board was designed with a 3 pin JST and capacitor on the Vcc but I will probably leave them off. The holes for the JST will make it easy to solder in the wires. Soldering on the Hoyt PCB sucks. This is the main downside and will not be for everyone. I suggest tacking the wires down then gluing them and rechecking the solder joints with a microscope or a loop. You do not want these joints breaking! The three posts on the backside of the assembly/bracket are actually pretty helpful for alignment and positioning in the print.
I think separating the trigger from the board opens up a lot more design possibilities. I wanted to provide the boards so we could see what else everyone can come up with.
Here is how I dropped it into my print. The three posts guide it as it slides in. The battery fits in the handle. I did have to add two side screws to hold the assembly in.
This is the print of the pistol. It was my 4th iteration. Took me while to get things right. My first print could only fit two fingers. This one fits good in the hand but too big. I wanted it to be small because I also do not want to be shot! So one trigger finger and two fingers on the grip. The pinky fits underneath. Overall I’m pretty happy with it.
Things to do:
It needs a trigger design, which I have not gotten to yet. Works ok with a “nub”
It also needs a bit of work for the interface between the two shells. I printed both with the interior side down which results in a great finish at the expense of those bottom/contact edges. I have only been printing for about a month so maybe someone would know a better way to print it.
Battery might need a little foam to keep it from moving. I kept the same battery but I would love to put in a 18650, I just wasn’t sure if I could charge that through the USB and would have to figure out the wiring.