Thrifty Alternatives ..Building Foam Campers

[GPW]

Thinking once the canvas is initially attached with the T2, it's not going anywhere, so once dry, just prime the exposed "raw" ish' canvas surface with a primer and paint ... no sanding Much as I have done with Oil paintings for many years.
For getting the canvas stretched tight , we first dampen it a Little bit with a spray bottle and water , then apply it over the glue base, stretching as we go ... when it dries , it's like a drum ..

For many years I've glued raw canvas on un-tempered Masonite panels . Gesso as a primer and then painted... Never had a problem ...

[Postal_Dave]

What I found out with my little experiment was, even without the canvas or T-shirt material, if you put down a coat of Titebond II and then paint it, it's very water tight.

I'm now thinking of using the watered down Titebond II like you'd use CPES.
Take a piece of plywood and apply that to the edges and let that soak in. Once that dries, coat the edge with Un-diluted glue and seal it up good.
Maybe use the diluted glue on the outside of the plywood to keep it from de-laminating.

What do you think?

[NathanL]

I posted it another thread on waterproofing but here goes anyway.

On some very expensive wooden boats nowdays to waterproof the deck above a cabin area and using canvas...

Put down a full strenght coat of TitebondII on the deck and place the canvas over it and let it sit overnight.

Next day spritz with water and iron the canvas to tighten it up. Coat with a thinned layer of Titebond II (thinned with water) but don't completely fill the weave.

Paint it. That's all they do and it last for years like that.

[S. Heisley]

Nathan:

I noticed that everyone is using TitebondII, not TitebondIII, for this canvas attachment process. Is there a particular reason for that?

Thanks.

[bravebluemice]

After reading a bit, I'd hazard a guess that it has to do with the cost/benefit.

TB2 is considerably less expensive than TB3, and from the looks of things, the the TB3 is going to be more critical in high stress, high heat, high moisture kinds of things. The TB3 passes a test where they boil a chunk of laminate. The TB2 passes a test where the soak a chunk.

Rockler prices for TB2 and 3 are 29.99 and 37.99 a gallon respectively.

Here's an interesting question, could the glued canvas be applied directly over foam as an outer skin? This could save me forty pounds!!!

~BBM

[NathanL]

Nathan:

I noticed that everyone is using TitebondII, not TitebondIII, for this canvas attachment process. Is there a particular reason for that?

Thanks.

Not that I'm aware of. I'm going to go out on a limb and say it falls in the "It has worked for us in the past so why change".

We're talking about a group of people who still buy pine tar etc...and complain about any new "fangled" stuff that wasn't around when Ahab was chasing a whale.

[S. Heisley]

bravebluemice wrote:

Here's an interesting question, could the glued canvas be applied directly over foam as an outer skin? This could save me forty pounds!!!

From my experience, Titebond glues melt Styrofoam.

[GPW]

Never found that ... not on our blue foam anyway ...

[S. Heisley]

Don't know about the blue or the pink. It melts the white Styrofoam.
I guess that means test it before you buy a lot of it.

[GPW]

Sharon wrote : " I guess that means test it before you buy a lot of it. "

That's always a good idea... Hopefully we can test things here saving everyone else the trouble... and the money ...

[Hillmann]

laursand,
Could you post an up close picture of the corner of your teardrop so we can see how you did your seams in the canvas?

[laursand]

Hillmann, I have this pic of the edges...



...for actual corners, I just improvised. Some could take a fold over of canvas, on others I couldn't afford the extra thickness. Most edges I am intending to cover with trim.

Sharon, the only reason I used Titebond II vs. III is that it was the one they used in the article I was following - nothing real scientific.

Laurie

[Tadlan]

Has anyone tried epoxy and canvas over foam? I know it wouldn't be as strong as fiberglass, but it should still be pretty strong. I was thinking of doing some cabinets out of this composite to cut down on weight and cost. Have some testing to do first, of course.

[NathanL]

Just my opinion but if you go to the expense of using epoxy you might as well do it over fiberglass. The money in 'glassing is in the epoxy for the most part - not the glass unless you get some oddball/exotic cloth.

[GPW]

The nice thing about the T2 is it can be thinned 50% and still work fine to attach canvas... Just gotta' be cheaper (Thrifty) than fiberglass , less messy/ toxic too (water clean up ) ... The old timers never had epoxy or fiberglass ... the canvas thing seemed to work fine for them eh ? ... and Laursand too