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Curious mind on system..

PostPosted: Tue Sep 03, 2019 3:49 pm
by RJ Howell
All my previous tests were with bedsheet as I was doing up the interior. Canvas is a whole 'other animal!!

My basic system failed because the canvas soaks up some much. As a approach to a save of the area I went back to my fiberglassing days and poured/toweled TB2 over.

That brought forward the thought/question.. Has anyone actually punctured (like using a wallpaper tool) the canvas and top coated (like fiberglass) with any sucess? I've read of a few doing this on the foam (which makes so much sense to me), but not yet have I read on anyone doing this to the canvas.

I'm assuming someone has and it has been dismissed. Just me being curious again.

Re: Curious mind on system..

PostPosted: Wed Sep 04, 2019 5:03 am
by GPW
RJ , Not that we know of … Although MUCH has been tried in the past 10 Foamie years … But sounds like a good test … ?

QUOTE: ( copied ) "My basic system failed because the canvas soaks up some much.” Actually I believe the canvas is supposed to soak up the glue to a point … even dampened canvas once drying would soak up some glue ( expected , wanted ) … My personal intent was to literally fill the canvas with glue or paint to make it a Flexible Fiber reinforced SOLID … Our FS skin feels like a thick piece of Leather ( Moo !!! ) … 6 years and counting Living Outside … ( My “test” of PMF ) :thumbsup:

Re: Curious mind on system..

PostPosted: Wed Sep 04, 2019 8:46 am
by tony.latham
I went back to my fiberglassing days and poured...


Have you considered glassing instead of PMF?

Image

:thinking:

Tony

Re: Curious mind on system..

PostPosted: Wed Sep 04, 2019 9:33 am
by John61CT
I do not understand why use TB2?

Not waterproofing!

Does it really save a lot of money relative to the overall project?

Re: Curious mind on system..

PostPosted: Wed Sep 04, 2019 10:28 am
by Postal_Dave
John, I just had some very good results in a test using TB2. http://www.tnttt.com/viewtopic.php?f=55&t=71976&start=15 It held as well as Glidden Gripper using a different application technique. (Once again, perform your own tests before applying to your camper build.) It is also only $18 a gallon too.

Re: Curious mind on system..

PostPosted: Wed Sep 04, 2019 11:03 am
by John61CT
Maybe just me, but I'm looking for not just strong adhesion, but tensile strength, puncture resistance, and most importantly,

full encapsulation of the organic materials - both wood and canvas - in a fully waterproof long-lasting "envelope".

Otherwise the whole "core" is subject to rot when (not if) the topcoat layer is breached. Like floating a home slab on unstable hillside clay soil.

Saving a few hundred in total is not important to me compared to worry-free longevity, and a very small fraction of the overall total cost of the whole project, especially counting my labour hours.

Re: Curious mind on system..

PostPosted: Wed Sep 04, 2019 11:52 am
by RJ Howell
tony.latham wrote:
I went back to my fiberglassing days and poured...


Have you considered glassing instead of PMF?

Tony


I did. Two main reasons I'm here: To learn about this Foamie construction method and to understand PMF.
I needed a small project to learn by and the Sleeper Cap (which I've always wanted) was perfect for this. I like what I've learned and how I can push this Foamie construction. Now I'm learning if I really wish to stay with PMF.

The judgement on PMF so far is the bedsheet is awesome to wok with and does a pretty nice job (my interior). This canvassing is a whole other animal! The Jury is out on the canvas PMF system.

Re: Curious mind on system..

PostPosted: Wed Sep 04, 2019 11:54 am
by RJ Howell
John61CT wrote:I do not understand why use TB2?

Not waterproofing!

Does it really save a lot of money relative to the overall project?


I am very curious... What did you use on your build?

Re: Curious mind on system..

PostPosted: Wed Sep 04, 2019 12:10 pm
by Pmullen503
The problem (or virtue) with foamies is that they are somewhat flexible. Canvas saturated with paint is flexible and waterproof enough provided water can drain off.

On a wooden TD, I'd definitely go with epoxy/glass, even under (or especially under) another covering like aluminum or FRP. You never detect water infiltration until it's too late. I think people who've never worked with epoxy and glass are scared off by the apparent complexity and cost of the components.

On a foamy, I think that protecting the wood with the "mix" or CPES and paying attention to make sure water drains off is probably adequate for PMF.

Re: Curious mind on system..

PostPosted: Wed Sep 04, 2019 12:14 pm
by John61CT
RJ Howell wrote:I am very curious... What did you use on your build?
haven't got one yet, but one day. . .

Re: Curious mind on system..

PostPosted: Wed Sep 04, 2019 12:48 pm
by RJ Howell
Pmullen503 , I do agree! :beer:

Re: Curious mind on system..

PostPosted: Wed Sep 04, 2019 12:50 pm
by RJ Howell
John61CT wrote:
RJ Howell wrote:I am very curious... What did you use on your build?
haven't got one yet, but one day. . .


When that time comes, I will follow what you end up doing. :)

Re: Curious mind on system..

PostPosted: Thu Sep 05, 2019 12:38 am
by Postal_Dave
John, you want to know how water tight PMF is?
71201
71200

A few years ago I picked up a couple of Priority boxes from my local post office and did an experiment to find out the answer to that question. I painted the inside of the box with TB2 and the lined the inside of the box with a "Jersey" bed sheet. I then used the TB2 on it again to soak the material and let it dry before I primed it and painted it.

Once they dried, I filled them with water and waited. After more than a week, it still hadn't leaked.

John, I'm not disrespecting you or trying to be hurtful when I say this. As a matter of fact, I'm trying to be encouraging to you when I say this. Buddy, you haven't built a camper yet, and you haven't done any experiments yet, however, you are our #1 Doubting Thomas. It's time for you to roll up your sleeves and get to work.
I suggest you pick up a bottle of TB2, take some old bed sheets, get a few cardboard boxes and try this experiment yourself. Do it several different ways. Try it with and without the primer and paint. Try it with just the TB2 and the sheets. Find a way that works. Do this right an you'll turn some cardboard boxes into buckets.
I'm looking forward to a thread of your experiment with a lot of pictures. :thumbsup:

Re: Curious mind on system..

PostPosted: Thu Sep 05, 2019 5:09 am
by GPW
You can cover one of those cheap $1 Foam Coolers with a fabric and that makes them last forever… Good practice on a small scale :thumbsup: a “Test" with something you can use later ... ;)

For compound curves you can use cheesecloth or gauze … which conforms easily to odd shapes … Too thin ?? Use a couple layers …

Re: Curious mind on system..

PostPosted: Thu Sep 05, 2019 11:17 am
by Postal_Dave
GPW,
John wants to know if what he makes is water tight. Those cheap coolers are already water tight so he wouldn't be answering his question by using those. However, he can graduate to a cheap cooler after he finds out that PMF, if made correctly, is water tight. :thumbsup:

Old trick for when you want to make a cheap cooler work better. Cover it in thick cloth, then wet it. As the water evaporates, it cools the cooler. :?
Be careful where you do this though. There will be a puddle and Mom doesn't like cleaning it up. Don't ask me how I know. ;)