PBS-4 Silencer

thingiverse

-- EDIT 24/03/2020 Following a recent comment, it seems the thread on the first version of the muzzle cap may be a bit loose (0.2mm oversize). I added a tighter version (only 0.1mm oversize). I will let the previous version since it do work fine on my barrels. Since some plastics shrink more than others, it seems appropriate to have options here. If it do end up being a recurrent problem, i will redesign this part in a more modular way (so you don't have to reprint the whole thing every time). Also i beefed up ever so slightly (+1% in diameter) the knurled ring, since i managed to split one thread from my print, i figured out it would'nt hurt to reinforce that part a bit. --EDIT 12/02/2020 I added a picture of the printed model. I knew the dimensions, but damn, that thing is huge. Also i will slightly modify the model to add a bit more material on the muzzle cap threads. If you lookk carefully i managed to snap the "smooth" part of the muzzle cap. (mainly because i rushed my print setting to gain time, but it is also quite thin). I may also slightly tighten the 14mm CCW threads. They do thread properly, but on lightly worn threads there is a bit of wiggle, and i managed to pull the thread on my first print (i may also have used a bit too much force here). This is a quick model of the PBS-4 silencer for airsoft AK. To make it easier to print, I separared the silencer in 3 elements. - A muzzle cap, with 14mm negative threads. I could have designed an insert instead of threading the cap directly, but i wanted to limit the number of screwed parts, to avoid alignment issues with the barrel. On the original, a little spring sheet is bolted on the front of this part. I did not designed it nor made the holes to accommodate for that, but they can be added post-print if required. - A main body, with threads on each end. I tried to keep the dimensions close to the original but they are not the exactly the same. I let a cylindrical 40mm (diameter) by 140mm (length) cavity inside so baffles can be fitted if wanted. I have no idea what kind of baffle design could be used for this right now, i may add some later. - A front cap, which just thread inside the main body. I kept it separated so it could be slightly adjusted for alignment with the replica. It's not the best way to do it, but usually work fairly well. Quick note: Except the 14mm CCW threads, all threads are positive, purpose made thread. They are large on purpose (easier to print, and a bit stronger). Except for the muzzle cap, all parts can be printed without support. The main body and muzzle cap should be printed conical side down. This is still a WIP, and i have not printed the part yet. I recommend to use strong filament for silencers (PLA just won't cut it outdoor). I would recommend ABS or poly-carbonate if you can print those. ASA may be a good alternative if not.