Here's the next update...I've been working away, making mistakes, changing my mind, breaking things (unintentionally), and dealing with tools that aren't quite the right ones for the job...
I picked up the portable table saw that was at my folks house. It's old and a budget model to begin with. I discovered somewhere along the way that the guide isn't square when it's torqued down. Before I realized that, I discovered that the table isn't big enough for the cuts I needed to make. I got it all worked out in the end, but I had spend a bunch of time getting creative, and paying close attention.
I picked up a miter saw blade for cutting the aluminum extrusions. I knew I needed a 10" blade, but somehow that 10" blade turned into 7.5" when I went to put it on. Since it was a smaller diameter, it wouldn't reach all the way to the floor of the saw, so I had to get a little creative again. I used a piece of 2x4 to get the extrusions high enough that the blade would cut all the way through. Got it done in the end. The extrusions aren't 100% perfect, but they'll work.
My initial plan was go with recessed latches, but I failed to consider the width of the latches in relation to the walls where they were going. With the extrusions in place, there wasn't enough wood to install the latches. I traced the latch and cut out the extrusion to get it to all fit, but it was pretty sloppy, and a lot of work, so I abandoned that idea. Now I'm looking at some surface mount latches.
It took me some time, I wanted to give up, but I didn't. I've got everything cut, mostly mocked up. It's a little crude, but it's looking like it'll be functional.
I need to order a few parts, paint the walls, do a little finishing on some of the extrusions, and put it together. Hopefully from here on out It'll be pretty smooth sailing.
