Pepakura vs. Sculpting

[Deathbox]

ok, i have come to a conclusion: if you plan on casting your pieces in molds them the best way to go is to sculpt the pieces on a model that is roughly your size.

i have Pepped and fiber glassed an entire War Machine suit and am now on the Bondo stage. no matter how much i sand and Bodno i cant get it smooth, i get close, but not quite. when it comes to clay though, its easy to get it smooth and is ready to cast once you sclupt the piece, there is no fiber glassing, priming, resin, Bondo, etc etc. i am very close to scraping everything and starting over with clay, if nothing else, i am definately doing my Iron Man Mark III suit in clay.

as for the Bondo/sanding step, i have skimmed the Bondo tones of times and sanded with everything from 60 to 600 grit sand paper by hand, on a sanding block and mainly an electric sander.

sooooooooooooooooooooooooooooooooooooo frustrating!

 

[Devious]

Did you wet sand?

The reason most people go with the pep method is because casting costs WAAAY too much for the average Joe. What you could have done was to RONDO your suit. This involves resining your pep on the outside, and then pouring a mix of resin and bondo so it coats the inside. This method requires no exterior bondo because you just have to sand down to the rondo.

 

[ShadoKat]

If you're really going to give up on bondo and start using clay, DO NOT scrap your entire pep build!!! Instead, be sure to check out surmainey's helmet build thread (called "had a different idea... went with it"). You will be glad you did.

 

[Hugh Holder]

ShadoKat is right, you can use a hardened pep as a very good armature to lay your clay down on. Things like retaining symmetry become less worrisome and you are right it does smooth easier.

Now free-hand sculpting is an art all on it's own, and I have a ton of respect for artist that use this method. But for me, I like to do all of my sculpting digitally, without the mess, and with ctrl+z ^_^

I found that after I casted my helmet I could easily smooth out my "2nd generation" helm. The plastic is sturdy and I fee like I have a lot of control taking 80 grit paper and working up from there. Yeah casting is pretty expensive, but it's a pretty good alternative to working with clay if you are a noob like me.

Also, there are more things that can go wrong when molding because of factors like the type of clay being used, certain release agents, etc.

If you think it's for you, go for it. But definitely experiment on small parts and do your homework before jumping in, or you may find sculpting from clay will be more expensive than you think.

 

[Arioch]

You can get finer grits than 600 of sandpaper. You can also use primer as a filler. Most greyr prime is labeled as a filler/primer. It may help a lot and primer will likely sand smoother than just bondo alone. Hope this helps.

 

[Deathbox]

i thought of the whole Pep and clay combo and was wondering how it would work, thanks for letting me know. i was thinking, instead of going for a perfectly smooth finish, the small dimples and "pock" marks would act like wear and tear marks on the suit. all i have to do is take them into account when i paint the final product.

also, i was thinking about casting it and then trying to work with the pastic cast piece i make or maybe looking into the spray paints that fill in small scratches. anyone have any experience with any ideas i listed or any other options? ... my main concern is the War Machine chest piece, its big, odd shaped, has small crevaces and big openings and would be a very large item to cast into a mold.

by the way, anyone have any idea about how much it costs to buy the materials to cast something the size of, say, a helmet? ... it will be the first time i mold anything and i think i may have the helmet done tomorrow if i can find something to sand thin stright lines (the HD jaw piece).

 

[box o crayons]

ok a noob intro to clay would be take your pep piece resin and fiberglass it and then use clay to smooth and detail once done cast.

 

[Hugh Holder]

also, i was thinking about casting it and then trying to work with the pastic cast piece i make or maybe looking into the spray paints that fill in small scratches. anyone have any experience with any ideas i listed or any other options? ... my main concern is the War Machine chest piece, its big, odd shaped, has small crevaces and big openings and would be a very large item to cast into a mold.

by the way, anyone have any idea about how much it costs to buy the materials to cast something the size of, say, a helmet? ... it will be the first time i mold anything and i think i may have the helmet done tomorrow if i can find something to sand thin stright lines (the HD jaw piece).

You can work with a casted piece for sure, a lot of guys will advise against it. I mean, it is pretty standard to want to make sure that your original is as close to finished as possible. But if you are like me, and are on a time constraint and just want to get it over with, you may find casting it and working on your 2nd generation version easier. I found that my casted part sands easier and more evenly than my original with bondo. The problem is, if you plan on casting more than a few and selling them, it will obviously knock your quality and prices down requiring others to refine their parts as well. Just a thought.

As for the material costs I was worried about the same thing. The most expensive thing for me was going to be the Rebound-25, but I was told that you don't need an entire gallon of it if you are only making a mold of a helmet. And I was actually able to get away with purchasing 2 trial size kits of Rebound-25 which came out to be around $15-$25 per kit. I think that's the price, sorry if I'm wrong. You can find prices on www.reynoldsam.com

What I got:

*2 Trial Kits of Rebound-25
*1 Gallon of Smoothcast Roto-65
*1 Gallon of Plasti-Paste II
*1 tiny small bottle of Thivex (you use this thing in drops so no need to buy a huge bottle initially)
*4 blocks of clay (optional for building wall in a 2 part mold)
*Mold release spray (can't recall the name, I'm not home sorry)

That's what I used to make the helm mold. There are other things to consider like cups to mix the parts in (16 oz) brushes and aluminum foil to help keep the outside jacket molds separate.

Hope that helps and good luck

 

[DarkBebi]

I am kinda in the same boat with OP on this besides the armor I am trying to make does not have a pep file so my only other way is cardboard/foam or sculpting, I know cardboard is not what I wanna do and their isn't many tutorials on how to really use foam to then cast and make a mold out of it. So I have to go the sculpting way. Now all the tutorials I see of the clay is they are using the 2 part mold with a clay separator, wouldn't that disrupt the finished clay piece? Or should I go the same way Ben used when he made his mother mold? Again wont that ruin the finished piece?

TL;DR How to harden NSP clay to make mother mold like Ben Streeper?

Sorry for Hijacking the thread in any way, I didn't want to make another thread and really didn't know where to post the question.