I have for future remakes, but I didn't take into consideration how many pieces I'd have to cut it into to print it when I designed it. I'm hoping the way it assembles distributes some of the stress away from the glue seams but I guess the only way to find out is to finish it!
I used a soldering iron to essentially melt and re-solidify the plastic on the seam edges, I forget whose video it was but I got the technique from a youtube tutorial. You're right about it being PLA, I haven't tested it with PETG yet. I'm not sure exactly how strong the welds are as the parts were mostly superglued together already, and I'm in no hurry to put the welds to a stress test and risk breaking the rifle again, but I can say for certain that it is stronger than just superglue and I will definitely be using this technique in the future. I have to practice a bit more because the welds aren't pretty by any means yet!
Update re: weld strength - idk if this is entirely a failure of welding as a principle or just how bad I am at doing it but take it as you will
I might try epoxy or another type of superglue, but I think I'm going to try and just weld the heck out of it and not worry about how it looks, then clean it up in post processing with some bondo and sanding. As far as bracers, I'd like to add them in future builds but I'd like to save as many parts of this without reprinting as possible so short of heat-setting metal inserts into it I think it may be too late to add to this build.
