Thanks Finhead - sounds like good advice. I guess when I normally rotocast a piece I'm putting the next lot of resin in the mould before the last one is totally cured, but it's a but harder to coordinate everything and film it at the same time. I actually sanded the bubbles out of the first coat before applying the second one, which probably helped it stick. Altogether I was just really happy that everything stuck to the foam.
Thanks for the tutorial XRobots, I'm actually working on an Ironman suit (Eva foam) and while I'm happy with how quickly it's coming together, I was a bit concerned about the texture once painted.
Has anyone ever used Smooth-On's shell shock in a similar context?
I have some 325 and some ONYX but they dont thix until just before setting.
Or did i jsut TLDR?
Shell Shock® Liquid Plastic Product Information | Smooth-On
I have no words to describe how happy this video made me when my friend showed me the link.
nice jobs XROBOTS . however what happen when the pva glue cracks inside layer between foam and smooth cast?.. will that cause the paint to cracks?
I don't really think you'll notice since the whole thing is covered in a shell of plastic?. The Smooth cast is bonded to the PVA anyway and the piece is quite rigid, so I don't think it would be an issue.longlenium said:
Last edited by XRobots; May 4, 2012 at 4:13 AM.
I have a slightly off topic question could you use the 65D rotocast that you used in the video to rotocast the inside of a Pepakura helmet made of paper? I'm just looking for a more reliable option of just mixing resin and bondo together.
Yes for sure, that's what it was designed to be used for (rotocasting) used to be called Smooth Cast-Roto.
endo500 said:
and it will make it strong enough to handle bondo and sanding on the outside.Finhead said:
How does this compare to the other Smooth-on products that others usually use for rotocasting. (Smooth-on 300 or is it 320)Finhead said:
Thing with 65D it is flexible not 100% ridged. For the foam the 65D is perfect as for paper the 300 series is far better IMO as it is ridged. For roto casting as in dry times etc they are fairly close.
Oh that is helpful to know that 300 is better for paper. I'm going to get some 65D to try his technique out and wanted to know if I could use it on the inside of a paper helmet i'm making as well.Finhead said:
I was wondering if you had tried "Rigid" versus the "semi-Rigid" that the 65D is. I use Rigid from Burman for other projects. I tested it on some foam with just some white glue first and it seemed to work out fine.
Is the reason for the semi-rigid used for its "give"?
also instead of PVA isn't Elmers White Glue basically the same thing?
This is an awesome idea. Thanks for sharing
Last edited by huttman; May 7, 2012 at 5:23 PM.
When it comes to using this method, could you use a pottery wheel to root cast a large piece like a chest plate?
So if I did want something more rigid, then the 300 would still be good on the foam? Like on some pink insulation or something like that? Instead of doing the fiberglass resin thing?
Out of curiosity, what happens to it with out PVA as a primer? It just peel off, or does it mess the foam up while cuirng?
Thanks for the great tut. Ill definitely be using this for my Bumblebee build. couple of questions.
How strong would you consider this technique in supporting weight. Im thinking for load supporting pieces such as the feet i should still use fibreglass. My build with all pieces considered and weight of myself on the feet pieces for example with probably total over 150kgs.
Does the sanding down of the final rotocast come up as smooth of a finish as say using bondo. For 'metal looking' mirror finish pieces, am i still better of using bodyfiller?
Did you 'water' down your pva. Ive watched STEALTHs tutorial on using PVA to seal EVA and thinking the 'watered down' layers sound like a good idea to prevent the peeling effect.
I'm not sure what you're planning on standing on, but if it's a bit of foam then it will still crush.McAullay said:
The only tests I've done for this technique are what you see, so I'll guess you'll have to try it - with work you should be able to get the same finish as a piece of plastic
I didn't water my PVA down, it seems to stick fine to the foam I was using.
The only time I tried it it kind of flaked off after the first coat, some was stuck on and the whole thing was a mess.Out of curiosity, what happens to it with out PVA as a primer? It just peel off, or does it mess the foam up while cuirng?
You need to rotate it in all directions ideally so that it doesn't pool anywhere.When it comes to using this method, could you use a pottery wheel to root cast a large piece like a chest plate?
Last edited by huttman; May 8, 2012 at 4:31 PM.
any comment towards using white glue? You were saying something about it needing to be water soluble in your video
Yeah the crushing is what I fear. I was considering using foam as the inner skeleton due to its light weight and easy manipulation but am thinking I may need something more sturdy.
I am just about 100% I'm going to have to use fiberglass to strengthen the entire piece as you can see in this picture the feet are split into thirds with a void directly below the foot (my feet will reside inside the wheel section).
Bumblebee Foot
I suppose I'm going to have to find out a-la trial by error. The plastic coating will definitely help with the other not weight supporting pieces at any rate so cheers for that.
Yes PVA is water soluble - are you asking about Elmers glue?. We don't have that in the UK so I don't know, perhaps test some and see if it becomes sticky again if you make it wet.huttman said:
PVA is basic white glue. It really comes down to what brand you are comfortable using. I would say for the U.S., Elmer's Glue All would be a good one. Also have heard that Aileen's is a great white glue, but I am pretty sure it is a lot more expensive than Elmer's. I wouldn't use school glue though, that tends to be a watered down version.huttman said:
Thank you for your replies. I got some glue all and am currently making a test piece. Only difference is I will be using "rigid" vs the "semi-rigid" used in the tutorial. I will post my results when finished.
Brilliant! I've been thinking about doing a foam suit but still wanted that glass/bonda kinda of finish too. This seems like a good middle ground for the two.
Reply with Quote