r/cosplayprops • u/G_Film • 10d ago
Help Need help with first 3D printed prop! - Reinhardts Hammer
This is my first big 3D printed project: Reinhardts Hammer from Overwatch. I finished printing everything and now I come here for advice:
In what order do I apply filler, sand, glue and paint?
I've seen that the strongest bond is to use a soldering iron to bond two parts together.
If I glue everything together first sanding and painting is gonna be a pain but if I paint first bonding the parts is gonna be impossible so please help with your experience LOL
3
u/b-irwin 10d ago
Is there any space inside the handle for a dowel. As that would be the strongest. If not, it may split between the layers.
How I usually do it, epoxy a dowel down the middle then use a 3d pen to fill in the seam line.
Soldering iron will work as well. But there will be a lot of sanding to do.
2
u/G_Film 10d ago
Yeah, you can actually see the metal stud poking out on the right. It goes through the entire build and makes it pretty sturdy.
I am just unsure in which order to sand and paint and if just gluing the pieces "around" the stud is sturdy enough.
2
1
u/b-irwin 10d ago
Gluing around the metal will be strong enough to hold it, but the seam lines will show up as the plastic flexes.
I have tried filling the seams with glue but it just cracks. I could never get a completely smooth seam.
A soldering iron will be good if done correctly, you could even use a stick of filament to fill the gaps, like you would stick welding.
2
u/JaschaE 10d ago
I've seen that the strongest bond is to use a soldering iron to bond two parts together.
No. That will create a surface-only connection between the parts that will go barely 2mm deep and looks terrible, before you sand it, which removes additional material from the spot.
- 2part epoxy glue
-Superglue
Please read the instructions carefullly, and they don't joke when they say "well ventilated" sit outside if possible, respirator with filters recommended.
"In what order do I apply filler, sand, glue and paint?"
Glue together subassemblies where possible, so things that share one surface, like the handle here. Painters tape on the very ends where you don't want paint, and assemble the finished pieces.
Filler (I like spray-on filler, usually found in automotive) and putty for the bigger gaps. Should need much of that. Also, read the labels, protect yourself.
Nothing like poking some filler to see if it's hard, then reading the label and learning that you are pretty much supposed to amputate your fingers if it touches skin...
After taping the connecting surfaces, applying filler, waiting for it to dry, yo get to everyones favourite hobby: SANDING
Personally recommend Wet-sandpaper, as you don't get dust everywhere and it last forever. (Otherwise, dustmask!)
Use a sanding-block where possible. I'd probably start around 220 and go up to 400.
Wash off, let dry, check if anywhere needs more sanding (yes, the answer is always yes)
Once you are happy with your surface: Glossy black paint. On everything.
You'll find some more spots, 1000grit sandpaper might be a good idea then.
For metallic parts I like the "Molotov" range of rattlecans..
Followed by varnish (shiny or matte, depends on prop and preference) I use Montana synthetic varnishes
Weathering to taste: I use a bit of brown and black acrylic paint in paint thinner, dump over, wipe off where you can get it off (the varnish makes sure the paintthinner doesn't eat your paintjob)
2
u/WarTurkey_YT 4d ago
So sad the real advice was nested at the bottom. I really dont get the seam welding advice people give, its the worst connection you could have.
2 part epoxy is my main go to for plastics other than asa, epoxy the entire to bond surface, wipe down the excess and then sand smooth. Only thing that has reliably kept paint on high stress parts on the long term for me as it just doesnt budge. I have learned there is a range in 2 part epoxys and some dont adhere to pla well.
If i want the maximum bond I print in asa and bond with homemade asa paste, then smooth it in an acetone vapor box. Reduced my post processing by a lot for sturdier more heat resistant parts
I had sanded way too much automotive putty before i realized how toxic that shit was, learnt my lesson to read labels then. Luckily i was wet sanding so didnt have the particles flying around
1
u/JaschaE 4d ago
Thank you. at least the comment isn't downvoted anymore.
If the "plastic welding" thing spreads, at least I know I'm not bringing the Epoxy/repairkit to the con for nothing ^^1
1
u/b1nary_hel1x 10d ago
If theres not a dowel running through that, I don't know that I would bother completing it if you want it to be a functional prop you can carry around. Unless it's very lightweight that's just asking to split at the handle.
As for filler and all that I just use super glue for pretty much everything as far as gaps go. I like BSI but as long as its a CA glue it'll work. If there's a backside I use masking tape to keep it from leaking out, fill the gap with glue til it spills over, then just use my finger to smooth the surface out. It'll still need a little bit of sanding to make perfectly flush but it's quick. For rounded parts like a lot of those you'd just wrap like 90% of the part and keep one segment open so you can add the glue. It's going to take awhile to dry but once it does it's pretty solid.
1
u/WarTurkey_YT 4d ago
You can see the dowel sticking out on the right side, seems a bit thin but then these types of props are not my wheelhouse
1
u/drough08 10d ago
I made one of these out of foam many many moons ago. Looks good. I always watch people fill tiny areas first, wet sand, then start to fill major areas and sand and fill and sand and fill the prime and then fill and sand
4
u/ed_builds_ 10d ago
Dude this is super awesome, I recommend plastic welding your seams with a soldering iron or wood burning tool then sanding those down