What is the best skin to put under canvas?

[greygoos]

Mike- Here is a link to expanded pvc in my area. They have it in 48 x 96 inch sheets and come in a variety of colors that also can be painted, machined, glued and screwed as well as being lightweight. They can provide 10 Mil but I have seen it online up to 25 mil. It is mostly used in the sign industry and is uv stable. Here it is is about 28.00 a sheet. I will try to get some samples. https://www.curbellplastics.com/Shop-Ma ... L.SkuSheet
Once again I want to thank all of you for sharing your knowledge and encouraging others to take the plunge. Jim

[GPW]

Liking the idea that it says “wood replacement” ... Maybe just use that for the Outside skin ? ... Some exotic tape for seams ???

[greygoos]

Just found out that the expanded PVC is available in 60 x 120 inch sheets as well. I might be closer to taking the plunge!!!

[dales133]

Talla, Cork sheet , although attractive , has no "tear strength" , and is certainly not smooth ... BUT , think how nice Cork sheet would look on the Inside , and you could pin stuff up on it too ( Maps , posters ,pictures , lists , reminders to self) ...


EDIT: But you have given me an idea for the 10,000 + wine corks I’ve collected.

Those wine corks make great looking noticeboards glued sideways onto a piece of ply with a timber frame around them.
I saw one at a market and made one for my mother.

[mikeschn]

Don't forget the other questions...

How thick would it be?
Would it just be a sub-layer between the Foamular and the canvas?
How heavy is it?
How flexible is it?
How well does glue stick to it?

Mike...

[greygoos]

Don't forget the other questions...

How thick would it be?
Would it just be a sub-layer between the Foamular and the canvas?
How heavy is it?
How flexible is it?
How well does glue stick to it?

Mike...

This link should answer most of your questions. It did mine but I didnt read it all the way through. https://www.acplasticsinc.com/techsheet ... _Guide.pdf
I would like to use it as a finished skin for foam.

[GPW]

Why not “TEST” a piece by making a smaller Foamie something ... like an ice chest /Beer cooler .... that’s worthwhile ... If you don’t think PVC is strong stuff, we make 40# Bows out of PVC plumbing pipe ( archery ) Expanded is just “foamed" PVC , just like everything else ... Worth a good test any way you look at it ...

Dale , corkboard , great idea , thanks !!!

[mikeschn]

Good idea Glen,

@Greygoos, whatcha gonna make?

Mike...

[greygoos]

A test sounds like a good idea, a tongue box might be a good start. I am waiting for the final thoughts on the generic foamie plans and maybe go with that. Contemplating making the trailer from strut. My cousins own an industrial supply house and my cost is only 10.00 for a 12 foot length and the connectors are neglible. Heavier than channel or tubing but it might be a good base for a Foamie.

[Alan_H]

Don't forget the other questions...

How thick would it be?
Would it just be a sub-layer between the Foamular and the canvas?
How heavy is it?
How flexible is it?
How well does glue stick to it?

Mike...

This link should answer most of your questions. It did mine but I didnt read it all the way through. https://www.acplasticsinc.com/techsheet ... _Guide.pdf
I would like to use it as a finished skin for foam.

I would suggest that the 3 mm is thick enough over foam, that's about 1/8" and with foam, the PVC and then canvas it seems as though it would be a pretty rigid setup.

Another question, is what other bonding agents will work, i.e. can you use epoxy and fiberglass over it, or would the curing process of the epoxy melt the PVC foam?

[GPW]

Questions all left for the testing .... seems all a bit “overkill “ to me ... Canvas over foam is pretty tough as anyone who has built one can attest ... Thinking if I was going to put anything under the skin it would be that open weave drywall fabric ... fiberglass mesh , super light but strong .... waaaay strong enough for camping ...

[Talia62]

Questions all left for the testing .... seems all a bit “overkill “ to me ... Canvas over foam is pretty tough as anyone who has built one can attest ... Thinking if I was going to put anything under the skin it would be that open weave drywall fabric ... fiberglass mesh , super light but strong .... waaaay strong enough for camping ...

Another fabric I haven't seen mentioned yet on these boards is Pellon non-fusible interfacing. Even the super heavyweight variety weighs very little, and it's nearly impossible to tear it. I'm betting it could successfully replace canvas as a skin, and I doubt you'd end up with the rough texture that canvas usually has.

[KCStudly]

seems all a bit “overkill “ to me

Me, too. Let's back the truck up here for a second. All of this talk about new materials is all well and good. Really, it is a good thing to explore new possibilities; and I am all for people sharing their test results and finding the thing that works best for themselves. Been there, done that. However, the original issue was how do we get a smooth, not lumpy finish on a foamie that will be covered with canvas (...or even epoxy/FG).

So cladding the foam with a hard board, be it PVC foam sheet, chip board, thin ply, multiple layers of thin paper, whatever; these all add extra materials and labor; and most of them, in order to be soundly attached would require the foam to be pretty damn smooth and fair to begin with (at least I, for one, wouldn't want voids in there). Not to mention that many of these options don't solve the issues of compound curves or rounded edges (which is one of the great benefits of foam in the first place; rounded edges means no trim, artful expression, designs that are ergonomic and pleasing to the eye, etc.).

So the way I see it, if you want to take full advantage of the foamie method, and you want it smooth, you have to do the time sanding and fairing the foam to get it pretty damn close in the first place. If that means block sanding, GS filler, vinyl spackle, vinyl spackle mixed with foam dust and TB2, whatever, that is the foundation that is going to make a nice smooth canvas job.

If you don't like the way the XPS expands and contracts at different rates than the wood blocking, or the way that the canvas overlaps stack up and leave visible seams, then either take a good hard look at epoxy/FG exterior skin, or some other form of fairing material after the fact.

The weave texture in the canvas isn't the issue. That covers over with a couple of good coats of filler primer (same as FG weave).

Just saying, when you boil it down, there are many ways to get the job done. After working with FG and epoxy for a while now, I don't think adding PVC foam into the mix would solve anything. It will have its own issues with seams and edges, lack of fairness, and bonding; and it will also add weight. I bet it would also push the cost of canvas right up there with FG and aluminum skin jobs.

Just saying, my FG skin is coming out smooth and fair, and it is as hard as nails; takes a hit and bounces back.

Just saying.

[GPW]

Smooth is the key word here... If you don’t care about perfectly smooth , then a Foamie is EASY ...

[Bob Hammond]

i don't recall seeing Tyvek mentioned in this thread.

A few years back I did some test pieces when I was noodling around about Teardrops, and the Tyvek stuck to the foam ok as I recall. I remember that the my biggest concern was deterioration by UV sunlight. I wonder if Gripper and house paint would protect it.

Well, I can't find my test pieces which is not surprising after so many years. But here is the thread:

viewtopic.php?f=21&t=57559