Intro to Fab. – Week 4

Enclosure

Had a few ideas to start out with but I think I’ve narrowed it down. I plan to build a simplified version of my midterm project from a Hacking Audio Hardware class last semester. I had this huge plastic enclosure I bought off of Amazon because I needed enough surface area for two faders, two knobs, three switches, two photoresistors, and a textile sensor — just on the top — on the sides there was also another switch for ON/OFF and a 1/4″ audio output. The goal now is to make a small oscillator with a cleaner and nicer enclosure.

Much nicer and cleaner than this:

Link to HAH midterm project – https://biancagan.com/2021/10/27/hah-midterm-project/

I promise, I’m generally more OCD with cable management but this was just horrendous.

The plan is to make a wooden enclosure, and I’d like to make it round. I feel like wood and a round shape isn’t usually a thing when it comes to audio hardware.

Here’s a quick sketch and also the circuit:

I’m going to use the laser cutter to cut out layers to stack and glue on top of each other to make the enclosure.

Started ordering and gathering my parts and made a bill of materials:

Took a field trip to Midtown Lumber and got a few sheets of (slightly less than) 1/4″ sheets of birchwood. Thankfully they were able to cut them into 12″ x 24″ sections.

I sketched out a vague idea of the layers I would need, as well as a schematic for my protoboard.

The layers consist of the top with labels and holes for the ON/OFF switch, LED indicator, 1/4″ jack, and two potentiometers. Another layer is a mid-layer that I will mount the PCB to, a bottom cover, and a layer that will be near the bottom which the cover will magnetically secure to, and the most used layer is the mid layer used to create space throughout the enclosure.

All of the layers aside from the top and bottom cover, have four holes to help with alignment when I glue and clamp them altogether.

Moved over to Illustrator and drew up the actual layers.

I did a few test cuts on some cardboard, as well as a small piece of wood.

Then I just went for it. I moved on to cutting some of the official layers. I didn’t cut out a top layer (aside from the test cut) because I still need to measure the actual size of the 1/4″ jack that I’m going to mount to it. I also did not cut out a bottom cover or the bottom layer because both need to be etched to a specific depth to fit the magnets, which haven’t been delivered yet.

I cut out 16 of the middle layer as well as a few of the PCB mount layer because I adjusted the spacing of the holes that the PCB/standoffs will screw to. Had a couple mishaps with some tear-out so I cut a couple extras to make up for them. Also after that, I now have a very large supply of generic wooden coasters.

Here’s what the enclosure looks like with test and actual layers together.

Maybe I’ll make the top cover removable as well?

Update: Got the last few bits I needed, so I soldered the protoboard and cut out the rest of the layers.

Next, I made sure everything fit through the holes and had enough thread for it to be mounted to the top. Then started to glue everything together.

Continued to put all of the layers together.

I knew this was going to be an issue (as I’ve ran into it before), but it was the last protoboard I had of this size — the corner holes for mounting the protoboard are smaller than the standoff screws that I own. I’ve drilled through them before to make them wider, so I figured I would do that again. It worked, except I broke one of the corners so it’s only mounted by three corners.

So, when it came down to the bottom layers and the magnetic cover, I cut out an additional piece so that I could glue two of the layers together and glue the magnets down. I had some issues mainly a superglue mishap and a magnet mishap where I got it stuck and had to dig it out. I’ll probably revisit the cover/magnet situation so that it fits better. However, it actually closes pretty well. I do need to add finger notches.

I haven’t completely secured the entire enclosure because I still want to sand it all down and maybe treat it with some oil. I also need to trim down the second pot so that the knob sits nearly flush to the top like the first knob/pot. Also, might readdress the whole cover/magnet thing.

Also, not that the circuit was really any part of this assignment, but it works which is cool.