Injection Mold Machine

This is a design I've been thinking about for a while. The original was hydraulic based, but for ease of programming, I went with pneumatic and added the traditional clamp system you see on injection machines. I'm making the prototype machine out of wood, and just had the clamp pieces laser cut today. The manual and auto modes are programmed aside from a few sensors, and everything works fine. Stay tuned!

M-11 Supressor Build - Mass Effect

My Mass Effect loving coworker gave me inspiration to build one of his favorite weapons from the series.

I didn't just want to make another model with lights, that's been done before. I thought it should have cool sounds, vibration, ammo counting, reload, and react to attaching the silencer, all while learning more about Arduino.

The model wasn't something I wanted to spend a weekend on, so instead of whipping that out over a weekend, I downloaded it off Thingiverse. The original model needed to have many tweaks, including making the interior cavities larger to accommodate the electronics (colored).

First prints of the model didn't turn out very well, so I switched from a plastic printer to a resin one. This gives much more reliable detail. It's definitely more difficult to work with than ABS plastic, and more expensive, but well worth it in the end.

This is a failed print of one of the larger pieces. I believe the supports broke off in a few places because they were too thin, causing the print to "bend" layer by layer in a few sections where it was unsupported.

I rubberized the grips with Plasti Dip. It goes on very thick, but shrinks down to a very thin and tough grip surface. It captured the details well enough. After the first coating dried, I went over it with a brush and a dabbing motion to add texture. I originally wanted  a geometric pattern texture, but I should have modeled that into the grip before printing. Dabbing was fine though, I'm happy with it.

I regularly checked the fit of all printed parts, especially after rubberizing. Eventually they would have to be joined by either resin or epoxy, then sanded flush to avoid seams.







The model was progressing slowly, but nicely. What I wasn't so sure about was the electronics. What would I want to include? How much space did I have? And what's a FTDI? ....


My desk was covered in all manner of circuit parts for months as I played with designs on an Arduino development board. I started with a very stable board in case I crossed my wires, and they did, a number of times. I also had to make a custom breakout board so there wouldn't be transistors or resistors floating around the interior of the gun. I wanted all the components to be organized.

This is the first design of my breakout board. You can see my non-standard diagram on paper as I figured out how to cram everything on that tiny board.

This is the final iteration of the board. I added a transistor for triggering up to 5 sound effects, and removed a capacitor I thought would power a door bell type coil for a kick.



Testing out the 24+ pins on the board. I knew it would be difficult to wire it up with stiff hookup wire, so I purchased some silicone coated wire for better flexibility.

Placement of all the modules went smoothly. I mounted some of the chips by adding bolts, then using epoxy to set them in place. Now the mounts are permanent, but the chips can be replaced if needed. I also used "green stuff" to help mount the motor, speaker, and battery. It molds to the shape of the part well and securely seats it. The nut that threads to the silencer was epoxied in place. The bolt on the silencer side was drilled out to show the light flash. It was then surrounded by a ring magnet. This trips the sensor hidden on the end of the breakout board by the bolt, which then tells the code to change from a loud shot sound to a silenced sound when firing. 

All the wires were then cut to size and connected. The connectors were cheap, so I made sure to solder all connections to the silicone wires and keep a tight fit on the pins so they don't slip off. 

Paint was next. For this, I sealed up the model, taped off any exposed holes or rubber bits, and primed and airbrushed some black with a hint of white. The white wasn't nearly as strong as I'd hoped, but it came out okay. I stenciled some design work in white. 

The side lights were cheap LEDs of the right color from some ice bucket lights I got off Amazon. They were cheaper than sourcing and buying individual LEDs. The diffused window they shine through is actually carved hot glue stick. It happened to have the right properties I was looking for. There's a charging port at the base of the grip, and uses the same micro USB cable a phone uses.

Coasters

A pair of laser engraved coasters for a coworker's gift to a friend.