Strengthening insulation foam to self support

[Epicurennerd]

So I am creating a large ring prop, I will be bending pic pipe into a circle and then using about 7 inches of insulation foam around that and glued to the pic pipe. There will probably be about 5 inches hanging without pic support. While I will be glueing multiple sheets together to strengthen it slightly I am worried about the blade edges as well as need something fairly cheap and easy to work with to seal the foam before painting. Someone recommended using super glaze or enviroTex Lite since they are epoxy resins. My question is will they help to support the foam as well as make it less likely for the foam to dent and ding? Should I encase the paint job in between coats of the resin or can I use a regular clear coat on top of my paint like I normally do?

I am normally a 3d print guy and I have some experience with EVA foam, but this is the first time I plan to use the blue/pink insulation foam from the hard ware store. Any hints, tricks, or videos are appreciated. Attached is an image of the prop to give it a bit of reference for my probably poor description.

 

[Rcw]

sounds like you would like to hard shell the foam on a budget.my from the hip suggestion would be to bond a thin metal rod to reinforce the outer edge.ive used tig rod “for welding” in the past as its strong and thin.This could keep the foam edge from getting dinged or chipped. 3m spray contact adhesive and the age old go to...tin foil can “hard shell” the foam without melting it. add as many layers as your ideal weight will allow.of course the more layers the stronger it gets.this also now protects the foam from whatever resin you like to use.another trick to create more mechanical bond is to crunch up the last layer of foil,the flatten it back down to bond it as the final foil layer.do a final spray glue wrap of everything with light,inexpensive fibreglass cloth and finish with your choice of resin.sand and paint like you normally would. Hope that helps.

 

[PlanetAlexander]

Just wondering, why not use EVA foam?

 

[Zinger]

I've had decent results using Smooth-On EpoxAcoat. Several layers will significantly stiffen the foam and it's a nice surface that paints easily.

What kind of facilities do you have? A guy at my MakerSpace makes amazing replica swords and Zelda shields by carving forms from MDF, using our large vacuum former to create shells of 1/32" plastic and then filling the shells with expanding urethane foam. The props are scratch and dent resistant, very sturdy and light and absolutely beautiful.

Fiberglass Blades