Pepakura Assault Rifle Help: Now What?

[ironman012]

I have all of the pieces of the high-detail assualt rifle with the grip and clip. I havent assembled them yet, because im not quite sure how i should make the entire model solid. I havent worked much with anything except bondo and resin...but using those seems very troublesome If anyone has any ideas, I would be very appreciative!

 

[andrew wukusick]

Someone on here before said something about hardening the outside with resin & using some great stuff expanding foam on the inside, but it sounded a little complex. I think it was blackroseimmortal but I can't remember.

 

[mkshane81]

phoenix 92 is right. it was blacrose. the trick is to harden it thoroughly with resin on the outside then use low expansion foam. Do a search in the weapon threads, you should find.

 

[box o crayons]

as long as theres a large whole (the butt stock) the expanding foam with resin applyed on the outside will go out that whole and wont warp your weapon

 

[TheSpartanMjolnir]

Wasn't there anoher topic almost like this?
Well what i said in the other one, you could first have the two halves open ( not glued together yet) Then you fiberglass cloth the inside, after that is done glue the two piece together and fiberglass the outside with just resin. But if there is a line of where he halves were, really carefully fiberglass cloth the line.

Expanding foam is a great method two, but if you're on the really cheap.
Then use the hot glue method by AOBfrost

 

[ironman012]

I tried using resin on the outside of an SMG i made a while back...and it didnt stiffen the cardstock any more. Did I do something wrong? (too much or too little catalyst??) ...also, expanding foam completely ruined the clip for my AR because i used it incorrectly- any suggestions this time around?

 

[TheSpartanMjolnir]

I tried using resin on the outside of an SMG i made a while back...and it didnt stiffen the cardstock any more. Did I do something wrong? (too much or too little catalyst??) ...also, expanding foam completely ruined the clip for my AR because i used it incorrectly- any suggestions this time around?

Maybe you should of fiberglass the inside first? Because if you do you'll have some reinforcment when your applying it with a foam brush.

When using expanding foam, use small squirts at a time, and don't have a huge mass of the foamy string, just make it small each time you use it. Look at Sean Bradely's expanding foam method.

I suggest using AOBfrost's " hot glue method" It'll probably more "Ideal" for you

 

[howaado]

After you coat the outside with resin you could try pouring some on the inside and rotate it to spread the resin over the inside walls. Then from there you can try filling it with foam.

 

[randomman]

I would recommend looking up blackrose's expanding foam tutorial if you haven't already.
I myself am currently working on an assault rifle (still cutting cardstock) but something I was looking at doing was slushcasting the inside of the resined model with a casting resin, like alumilite or smoothcast 300.
I know some people do that for helmets or other armor parts.
But yeah, if you're planning on using expanding foam you're going to want to look at blackrose's tutorial here:
http://405th.com/forums/index.php?showtopi...mp;#entry221737

 

[ironman012]

I would recommend looking up blackrose's expanding foam tutorial if you haven't already.
I myself am currently working on an assault rifle (still cutting cardstock) but something I was looking at doing was slushcasting the inside of the resined model with a casting resin, like alumilite or smoothcast 300.
I know some people do that for helmets or other armor parts.
But yeah, if you're planning on using expanding foam you're going to want to look at blackrose's tutorial here:
http://405th.com/forums/index.php?showtopi...mp;#entry221737

can you direct me to the slushcast thread (if there is one)?? I've heard of it...but dont know much about it.

 

[randomman]

can you direct me to the slushcast thread (if there is one)?? I've heard of it...but dont know much about it.

It took me way too long to find this, it should be stickied! </rant>
http://405th.com/forums/index.php?showtopi...smooth+cast+300
I'm not sure how much the casting resin can cost as opposed to expanding foam, but (this is just my opinion here) that this would make a stronger model, wouldn't it?
At the very least you'd have less chances of destroying your pep, but again, just my opinion.

 

[Slimguy379]

i would agree with the expanding foam idea. and yous some clothe on the out side of oi and sand it.

 

[TheSpartanMjolnir]

i would agree with the expanding foam idea. and yous some clothe on the out side of oi and sand it.

Well.. clothing the outside would loose all the details, and we want a good AR

 

[ironman012]

I think im going to end up resin-ing the outside multiple times...and foam the inside using the *quarter-inch-hole* method. Any tips for resin? ive had terrible luck in the past when not used with the cloth.

 

[TheSpartanMjolnir]

I think im going to end up resin-ing the outside multiple times...and foam the inside using the *quarter-inch-hole* method. Any tips for resin? ive had terrible luck in the past when not used with the cloth.

From what i've heard, if you resin the outside so much it's going to warp without the BACK reinforcement. So do about a layer maybe 2, then foam the inside little bits at a time, then resin the outside more if you want

 

[ironman012]

From what i've heard, if you resin the outside so much it's going to warp without the BACK reinforcement. So do about a layer maybe 2, then foam the inside little bits at a time, then resin the outside more if you want

Well...I think im going to make the AR in two pieces- top and bottom. Ill resin both sides, so i have better access to cavities that would otherwise be sealed off. Do you think ill have any problems assembling the two halves after resined?

 

[Ruze789]

I think that doing a slush-cast with the Smooth-Cast would work just fine. If you build a pep model with the intention of pouring casting resin into it - i.e. not leaving large gaps/ holes, sealing any holes that do exist - you shouldn't have much to worry about.
I don't know how much a weapon would use, though. I'd love to try it out to let people know but I don't see the advantage of a pep weapon over a wood one.
It would be very easy though. Build weapon, seal holes that resin might leak through, mix resin, pour resin in, rotate, repeat.

 

[Slimguy379]

Well.. clothing the outside would loose all the details, and we want a good AR

yes true but if you puncture a hole and spray "great stuff in the little at a time , fore it will expand and possibly stretch the cardboard. but on some flatter areas, clothe on the out side along with bodo, and some sanding may be the way to go

 

[TheSpartanMjolnir]

yes true but if you puncture a hole and spray "great stuff in the little at a time , fore it will expand and possibly stretch the cardboard. but on some flatter areas, clothe on the out side along with bodo, and some sanding may be the way to go

Sorry, but i didn't understand most of the parts you said. Clothing the flat areas is good, but then you got to trim the excess. And the ammo counter area has a hole in it to put the great stuff already. So basicly this would be how i would do it
Sugestion:


Resin the outside with one layer w/ a foam brush
Spray little bits of foam, and add a spray of water ( Sean's method)
Then let that dry, and do it again till it's full
Then you may add an extra layer of resin outside.
And then bondo,sand,paint

 

[ironman012]

Im about to assemble to two 'pieces' of the AR. Ill post pics once i have them fashioned together in some way. I left the ammo counter out, but the rest is unmodified. What would you experts suggest that i do with the foam, as far as methods with best results?