Both times I tried cutting through all layers at once, all glued together. You guessed it, didn't happen.
This time I bit the bullet and used (read: bought) Bill Doran's blueprints for better sizing, though I made some small adaptations of my own so that I wasn't outright copying him lol. I got a bunch of 1/4 and 1/8" MDF sheets and started learning how different a band saw and scroll saw are.
After that it was etching and beveling ALL of the things!
A few more details, more filler, the barrels, more sanding, more filler, and more sanding, then a final coat of primer to check for anything I might have missed. Oh, and more filler and more sanding. ;)
Anyway, got the silicone and some casting resin, and went back to start claying!
That night I went to open the mold and found out I hadn't sprayed enough release. A good chunk of the two halves were stuck together, and I was super mad - I thought I had literally lost a hundred dollars worth of silicone (which I couldn't lose). Luckily I was able to find several spots that weren't stuck to each other and carefully pry it open. The mold, thank all that is holy, was saved!
Then I started pouring the resin. Sorry, no pics of this part. Lots of tutorials on YouTube. Anyway, I mixed the resin several times, filled some of the cavity with pink foam to save some of the resin, and poured a huge chunk of it everywhere because the pour spout was too small. The end result of that one was me extremely pissed and a casting I couldn't save. I'm keeping it as a reminder to take it slow and easy.
Tried again after cutting a wider spout, and succeeded! Well, mostly:
All was not lost, however! After tape removal (always my second favorite part):