ive made a helios body a while back... i used plaster for my mold let me find the thread..........here it is.. http://www.rccrawler.com/forum/showthread.php?t=166189
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Step by Step ... HOME MADE BODY
- Thread starter GJM
- Start date
ive made a helios body a while back... i used plaster for my mold let me find the thread..........here it is.. http://www.rccrawler.com/forum/showthread.php?t=166189
you can but it will easily crack when you crash, really you want to use lexan
jwalker
RCC Addict
this is a great tutorial, i might have to try it out. i have been thinking of doing something like this."thumbsup"
509 Media
Quarry Creeper
Very cool.
Shadow Fox
Rock Crawler
indeed..cool tutorial...i'd like to for mmy own body for my Slash...I'll try it out! I got all the materials readily available..
very cool!!
very cool!!
ColquittCustom405
I wanna be Dave
nice write up!
crawler_clod
Newbie
takes the saying "i built that" to a whole new level"thumbsup""thumbsup""thumbsup"
GrndLvls Brain
Newbie
Sweet write up, now I have another reason to go to the shop and use the vacuum table we built not to long ago. Now if only I can think up a design I like..... If it its even still setup, let alone have the material still.
mcss aerocoupe
Newbie
Would a vacuum mold work on a scale accurate model? I really need a lexan body of a '66 Chevelle. An image of the model is below. I have taken the frame and interior away, leaving just the body, grill, bumpers, hood, doors, trunk lid, and front/rear windows in place.
My biggest worry, from reading this and similar articles, is since the body is metal, there would be poor suction, and therefore the resulting lexan car body would not be as good as it should be.
Also, since the body curves back in at the bottom, how hard will it be to get the lexan off of the metal body?
Thanks.
My biggest worry, from reading this and similar articles, is since the body is metal, there would be poor suction, and therefore the resulting lexan car body would not be as good as it should be.
Also, since the body curves back in at the bottom, how hard will it be to get the lexan off of the metal body?
Thanks.
mtnbiker93
Pebble Pounder
where did you get that sheet of petg for so cheap??? i cant find it anywhere
ARC MotorSports
Rock Stacker
Very cool thread!
Nice work.
Nice work.
bigal53021
Rock Stacker
the closest PETG that i could find is on http://www.mcmaster.com/#petg/=8naicw it is like $6.59
spacephrawg
Pebble Pounder
There are a few good reasons you can't mold Nikko, Tamiya, and other brand's hard bodies and/or lots of other options and that is that they have undercuts, that is, places where form curves under or has a protrusion or incision large enough to catch on the vacuum formed plastic when you try to lift it off. The reason why OP's thing works is because he had to destroy the original mold to get it out. You can't really do that effectively when you're pulling from something harder like a hard body. Look at any lexan shell body you own: they all get wider as they go to the bottom or at least not narrower. This is so they can pull the plastic off of the mold in the factory.
There is a way around the problem of undercuts, which is to make a mulit-part mold that can disassemble inside the cast shell after everything has cooled down. You'd have a keystone piece that you remove that frees up everything else. An Axial rep told me once about his time working for HPI, and how they had such a mold for a Camaro body.
The seam lines where the mold parts meet up will show in the casting so it helps if you've divided up the pieces along panel lines of the real car (not sure if that makes any grammatical sense but I hope the meaning is clear.)
Apparently, manufacturers drill vacuum holes all over the molds in places there they want detail to pick up. For instance that right angle where the windshield meets the hood, or where a bulging fender meets the body, or in the corners of windows so that the plastic picks up the detail there too.
About working with Lexan, Lexan is basically "polycarbonate". There exist generic clones of it just like there are for pharmaceuticals.
A tip I picked up recently was that you should pre-heat the plastic for a little while before you heat it for molding, so as to get the moisture out of it because that kind of plastic is a "hydrophile".
There are a load of other tricks to make this work that professional manufacturers use, that you can learn about on the www.tk560.com prop-making forums. They also talk about how to build better vacuum forming machines with more effective vacuum pumps and built in heaters.
There is a way around the problem of undercuts, which is to make a mulit-part mold that can disassemble inside the cast shell after everything has cooled down. You'd have a keystone piece that you remove that frees up everything else. An Axial rep told me once about his time working for HPI, and how they had such a mold for a Camaro body.
The seam lines where the mold parts meet up will show in the casting so it helps if you've divided up the pieces along panel lines of the real car (not sure if that makes any grammatical sense but I hope the meaning is clear.)
Apparently, manufacturers drill vacuum holes all over the molds in places there they want detail to pick up. For instance that right angle where the windshield meets the hood, or where a bulging fender meets the body, or in the corners of windows so that the plastic picks up the detail there too.
About working with Lexan, Lexan is basically "polycarbonate". There exist generic clones of it just like there are for pharmaceuticals.
A tip I picked up recently was that you should pre-heat the plastic for a little while before you heat it for molding, so as to get the moisture out of it because that kind of plastic is a "hydrophile".
There are a load of other tricks to make this work that professional manufacturers use, that you can learn about on the www.tk560.com prop-making forums. They also talk about how to build better vacuum forming machines with more effective vacuum pumps and built in heaters.
