t_vago's compound curve foam board pickup aeroshell

[NeilBlanchard]

3M 77 spray glue dissolves EPS foam. I found this out putting the paper plots onto foam when I was making my 1/4 scale CarBEN model.

[Varn]

77 spray works excellent on pink board, I am not soaking the pink board just misting some on it to let the composite stick to it while the epoxy is brushed on. Epoxy won't cause significant degradation either, I have never used styropoxy.

There is no reason to let a layer of epoxy cure on the surface before using the composite.

I was able to remove much of the foam from low stress areas once I built it.

Develop your technique on composite before you commit your beautiful foam shell to learning a technique. Like others have said. Complete the shape before working on hardening it.

[jime57]

Originally Posted by NeilBlanchard

I made a quick attempt in SketchUp ......

Neil, I was looking at SketchUp from Google. Do you have the free version or the "professional" level? Will the free version generate rib profiles?

[NeilBlanchard]

I have the Pro version, but the free version can do this, too. There are very few differences between the free and the Pro version; like maybe DWG file exports, and maybe a few other things?

[jime57]

Originally Posted by NeilBlanchard

I have the Pro version, but the free version can do this, too. There are very few differences between the free and the Pro version; like maybe DWG file exports, and maybe a few other things?

I'm a bit confused by your answer

Will SketchUp free version allow sectioning of the rendering, which I think would show the shape of the required ribs? It seems that that capability is central to using SketchUp for this form of modeling. Correct me if I'm wrong. Thanks

[joggerfogger]

Yes you can. I have the free version.


I also made stations at 10.25" apart on this one. If you are careful to use the exact dimensions of your truck bed rails and the back of your cab, you can extract dimension points from anywhere on the model.

I plan on taking these dimension points and measure them out on the plywood to make my stations.

[joggerfogger]

Another cool thing about sketchup: Once you have these shapes worked out, you can draw a 4'x8' sheet in the program and fit all the pieces onto the sheet so you can plan out how to waste as little plywood (foam, coroplast, PVC, etc.) as possible.

[bondo]

Originally Posted by Varn

77 spray works excellent on pink board, I am not soaking the pink board just misting some on it to let the composite stick to it while the epoxy is brushed on. Epoxy won't cause significant degradation either, I have never used styropoxy.

There is no reason to let a layer of epoxy cure on the surface before using the composite.

I was able to remove much of the foam from low stress areas once I built it.

Develop your technique on composite before you commit your beautiful foam shell to learning a technique. Like others have said. Complete the shape before working on hardening it.

If you use epoxy resin, you should have no problem except for paying three to four more times the cost of the cheaper polyester resin which I assumed you meant when you said fiberglass. Epoxy will not attack the pink foam, no styrene in it. Polyester resin will make pink foam look like the Wicked Witch of the West after she has had water thrown on her.

Bondo

[skyking]

Indeed. It rips the stuffing right out of it!

[t vago]

Heck, pretty much anything causes styrofoam to look like glop. Brake cleaner does an especially nice job of attacking it.

3M™ Spray Adhesive for Styrofoam® Brand Foam appears to be a nice exception. I tested a scrap piece of 1/4 inch sheeting with it, and this stuff did not eat the sheeting.

I was toying with the idea of using this spray along with 6 mil plastic wrapping for construction use, but the plastic did not really want to stick to the sheeting. It would stick, but it would also peel off the sheeting fairly easily.

I was also toying with the idea of using garage floor epoxy coating, but that stuff is expensive.