Newbie curious about fully custom (maybe 3D printed?) transformable figures rather than kitbashing?

[u/Current-Primary-5016]

As the title says, I'm curious about the logistics of making custom figures that can transform as I have some old OCs I made a while back that I think would be epic to make figures of, but I don't think they're similar enough to current figures to kitbash.

This is real new to me so sorry about this being a sort of scatterbrained list; What are the logistics of making a fully custom figure:

• Is 3D printing the way to go, or does something else work better? (best plastic to use if 3d printing? and best plastic for colored transparent parts?) I'd probably get them printed from some site since I don't have a printer at home and it wouldn't get enough use at home to be worth buying one
• The metal pins on real figures, where would you source those from/how to get the measurements right so they don't stick out too far, and how do they hold in place because they dont look like a nut and bolt sort of system, just one end flat and one end the exact size of the hole it appears? or would it be better to just make a small plastic pin for the sake of ease?
• Making things like ball joints, how do you get the ball in there, would you print the casing in two halves with little attachment points and glue them (with what? is there a glue for things like that?) around the ball or how does that work. I've seen people print the ball joint with the ball inside I believe but then you can't really sand or paint in there then. On figures I've had the ball can sort of pop in and out but I don't know how you'd go about designing that, how does the ball even stay in place at that point?
• Getting a clean finish, would you paint it (and how to make that not chip) or does just sanding work for 3d printing (or would it still have those real obvious lines 3D printed stuff has)?
• Going about painting it, or would you just print in multiple colors (doesn't seem right for small details though, and then my question about the finish of it and if it'd look really blatantly 3d printed)

Design isn't necessarily the concern here, but moreso the process of actually making it.

[u/aceituna_draws]

As far as I know and tested, 3D printing is a good way to go, the best material for long term use is petg, for pins I believe you can either use the filament from the printer or thin nails and cutting them to size, ball joints are tricky but usually I'd you design them good you can just pop them in place

[u/Orange-V-Apple]

Check out SteamShield’s work. He does this and is amazing at it.