FDM printing is a bad idea for any material in a sex toy.
There’s several issues:
eventually, it’s going to delaminate. Worst case you catch it and it just causes some minor lacerations.
Worst case? Shards of plastic stuck in your ass (or where ever,) while surgeons get intimately acquainted while playing a game of Operation. Only it ain’t a buzzer Making that noise.
Secondly? Hygiene. FDM laminations create a bunch of ridged parallel to the print direction. These ridges (and cracks that form at them,) can harbor shit loads of bacteria and are best treated as single use (ie food safety.)
ASA/ABS can be vapor smoothed with acetone but that causes other problems.
Your safest approach is to use a “mold” setting in your slicer to print off two clamshell molds which you can then cast a silicone rubber version. If it needs some added stiffness…you can add printed parts inside and submerged in the cast.
A potential idea after reading the bad with attempting the PETG route would be to create a mold from the 3d print.
Look into silicone casting. Or whatever grade you would legit need to be safe. Not sure if pure silicone is the right route or not. At least it’s an idea of a starting point.
Wouldn’t it still require a tremendous amount of sanding down the 3D print to get the mold to actually be smooth? Depending in the intended goal, the shape may make it hard to sand it down.
And yes, I WILL assume some utterly degenerate and non-conventional shapes if you start a conversation on 3D printing buttplugs.
You could always try printing in ABS and do an acetone smooth to make it a nice surface There are also filaments that can be smoothed with IPA (isopropyl alcohol) that might work so long as the goal is just to make a mold.
For single use, sure there’s food safe grade petg. However there’s tiny pores between layers that would make it impossible to fully clean. There are lacquer sprays, also food grade for sealing prints or print in asa or abs and vapour smooth it. Happy butt stuffing.
Bad idea to use a print, regardless of how you safety treat the surface. PETG does have fairly strong layer bonds, especially if printed at 100% infill.
However, since printing quality can’t always be guaranteed, it’s always safer to use the print to make a mold and then you can use silicone or epoxies that are safe for this particular use case.
Worst failure case that I have seen that could apply here would be an extruder that intermittently skips. If you have a couple of layers that aren’t printed correctly and not enough filament is extruded, you could potentially have a print split in half at the worst time.
Additionally, especially with cheap filaments, QA is really bad and you probably will not know what additional additives have been used. This could cause strength issues, not be ideal for internal use or completely incompatible with how the surface is treated.
If you get one made from the implant grade material (and manufacturing process): sure. If you want to print one at home: evidence inconclusive, do NOT recommend / won’t clean easily / just. don’t. bother.
I can’t believe I had to remake this alt already… I thought I was done with this shit. Alright, gamers listen up. I assume that you have reasons for not just buying a butt plug so you probably also don’t want to buy lube or condoms. Desperate times call for desperate measures. Get some plastic cling film from the kitchen, saran wrap. Go trifle through that medicine cabinet and find yourself some Vaseline jelly (you don’t want any scents or additives, just get the pure 100% petroleum jelly). Now that you have yourself some suitable condoms and lube the world is your dildo. I would recommend against screwdriver handles. I would also recommend some thermoplastic over 3d printing. It’s much stronger and can be infinitely re-melted down allowing you to conceal evidence of your indiscretions against god as well as being, much more importantly, hand mold-able to any shape you desire and it will be smooth without any need for sanding. This will allow you to experiment with different sizes and shapes in preparation for the fateful day when you can comfortably purchase a real butt plug. God speed to whoever needed to read this and for the love of christ, just ask a friend if you can deliver a real one to their house instead.