1 off Robocop Gun

[shavoc]

Hi all,
First time posting anything build related... anywho. Halloween is fast approaching and I have a halloween themed wedding to go to with lots of good friends.

A decent robocop in 2 months... we'll see. I started the helmet (I'll post pics when I get it to a reasonable stage) and I did the gun today.

I created a low definition version in Cinema 4d, exported to obj, then into pep for unfolding. I'm not the best "unfolder" so it was a p.i.t.a. to put together but it's essential 4 pieces. Here is how far I am now (currently) the first layer of resin is hardening on it.

I'll be working on this all night so I'll be updating frequently. I left out a few major details like the trigger itself, the sights, and the magazine. I'll be crafting those separately to add in later I just wanted to get the base done.

But I have a question:
As you can probably tell I'm not able to get inside the gun to reinforce it with rondo/fiberglass... and the gun is sectioned off in blocks (6 closed of parts [handle, trigger guard, and the piece that make up the top of the gun).

Is it feasible to layer on 3-4 layers (or more) of resin on the outside, cut it in half, dremel out the paper, reinforce it then merge it back together?

For clarification this is how the gun is sectioned off it their own little boxes (to make it faster to pep)... and part of the problem for inner reinforcement:

 

[Saber]

When I started on my Assault rifle, I was really nervous about figuring how to harden it as well. Granted, my AR wasn't sectioned off as your gun is, this is what I did:

After pepping the file, I applied about four layers of fiberglass resin to the surface.Then I sanded (VERY carefully!) off any resin drips, making sure not to accidentally sand through the paper. To add to extra detail, I bought some craft foam found available at any craft store (the almost paper thin kind), and cut out pieces and glued them to the gun. Following that, I added another layer of resin solely to the foam (keep sure that it's thin) to harden it (It may need a second coat, depending on how much resin the foam absorbs).
If you want to seal seams in the craft foam, you can also use a little bit of bondo, kinda like spot putty.

To harden the inside, I cut a small hole in the gun and then, in small bits, filled it up with expanding foam. Seeing that your gun is much smaller than the AR, I would be VERY careful about how much expanding foam you put in at a time. Probably nickel sized portions at a time.
Once the gun is filled up and the foam has fullly cured, you can cover up the hole with bondo, or another small piece of craft foam. Which ever your preference.

Just be sure to take my word with salt because my method may not be the greatest, but it's that way that I hardened my gun and it works for me. Be sure to ask other people before and if you choose to use my method, because other people may have a better idea as to what to do.

There are other methods like Rondo (a mix of bondo and resin) on the outside and inside, or even the method that you described with the cutting of the gun in half and then hardening it from there.

In any case, I hope you find a method that works for you!

Good luck on your build!

 

[shavoc]

Thanks for the advice... as it stands now I've got 2 1/2 layers on the gun in resin. I'm toying with the idea of dremeling out small flat square portions near the inner walls to remove the walls (hopefull easily)... then drill a cut a dime sized hole in the butt of the gun... tape over all the other holes I made and pour a semi-thin mixture of rondo in, tape over the butt hole <- hahahaha. and slush it around the entire time until it hardens. Either way I go, I'll let you all know how it turns out :|

EDIT:

I basically want to be able to fill the gun because I want to dremel in extra details that pepping would be ridiculously impossible - if I fail I'll likely build it up in (non corrugated) cardboard and hope for the best. I mean it is a pretty simple gun but it's really the first time I'm trying to build one

 

[Hyperballistik]

Rondo is your best bet, just thin it out with a little more resin than Bondo, and it will almost be jsut like using Smooth Cast, Just cut out 3 sides of a square, pour the rondo in pust the cut flap back in place, hold your finger over the hole and slush it around, it will work,but Rondo does have a tendency to shrink whlie it cures so it may warp the gun a little

 

[shavoc]

Rondo is your best bet, just thin it out with a little more resin than Bondo, and it will almost be jsut like using Smooth Cast, Just cut out 3 sides of a square, pour the rondo in pust the cut flap back in place, hold your finger over the hole and slush it around, it will work,but Rondo does have a tendency to shrink whlie it cures so it may warp the gun a little

I was able to cut flaps where they wouldn't be highly visible (not that it really matters) but I was able to cut/dremel out all walls including the trigger guard, did about 8 ounces of rondo... just SLIGHTLY more bondo than resin, plenty of hardener for both... I slushed the entire thing until I couldn't feel/hear the liquid moving around. Set the gun down with the handle taking the angle so it would be slightly heavier than the barrel. I'll post picks after it's hardened completely, tape removed.

Thanks for the suggestions guys!

 

[shavoc]

Update:

Here's the picture of the cutouts I was able to make, hard to see but here's the picture as promised:

Cut a window out above the handle, a small window near the triggerguard/handle, and a giant flap under the barrel housing. Just checked the gun it's solid, very warm right now (at least I got the mix right?)

I'm in the process of making a cardboard backup... also considering reworking the 3d model for possible distribution.