Beading and Flashing

Canvas covered foamies (Thrifty Alternatives...)

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Beading and Flashing

Postby Shirestone » Fri Jul 03, 2020 1:19 pm

I have read a number of posts regarding beading and flashing. I would like to use this method for my foam built but.....
I live in Canada where Gripper is not available unfortunately. I have tried Lowes, HD everywhere...still nothing.
Does anyone have suggestions for attaching beading or flashing to foam without using Gripper? I have read that Great Stuff may be my only option. I would prefer to use something else as the mess and the expansion effect (even after flattening it) is a pain.

Also I will need to attach the canvas to the flashing as well. Any suggestions for this as well? Obviously it will need to stick canvas to aluminum.

While I am at it? What is everyone using to fill in cracks between foam pieces or dents etc. that leaves a nice smooth look after sanding. Once again I would prefer not to use Great Stuff.

If in the end if I have to use Great Stuff I will but just looking for any alternative.

Thanks again for everyone's help.. really learning alot here.
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Re: Beading and Flashing

Postby ghcoe » Fri Jul 03, 2020 9:03 pm

Having introduced flashing to the foamie world I have stepped back a bit on it's usage. I do believe it is useful still in certain areas, but I now recommend if using it to install it on the outside of the canvas instead of under it.

Some of the reasons.
-Fairing in the flashing takes a lot of time and effort.
-I have found that two layers of canvas on the edges glued down with full strength TBII is quite strong in itself and I think in most cases really does not need extra reinforcement. If the area does need some reinforcement then I recommend now to install the flashing on the exterior. The reason is that if a edge does get damaged enough to wrinkle the flashing it will stay wrinkled. Foam will self heal in most cases. Exterior flashing would be easily removable and replaced if needed.
-Flashing being metal has a different expansion/contraction rate than the foam. Overtime it could work on the fairing in work and delaminate. I have not had this issue yet, but I do think it is a possibility.

I still think flashing, if done right can make a foamie stronger. Design has to be thought out though. Still makes good hard points for hinges and strengthening spans.

I glued flashing on with Great Stuff. You have to spray it on then then smear it on with a stick of scrap piece of foam. Once you smear it some it usually does not foam up as much. I also used Dap Latex Caulk and it seems to work good as well. Latex caulk is basically thick latex paint. Gorilla Glue Construction Adhesive should work too.

I use light weight spackle to fill in seams and dents and dings. It sands pretty much the same as the foam as long as you don't let it set up for a week or so.

I prime over everything before I canvas. TBII sticks to primer real well, so as long as the primer will stick to the flashing or aluminum it should work for canvasing.
George.

Gorrilla Glue, Great Stuff and Gripper. The three G's of foamie construction.

My build viewtopic.php?t=54099
Working with flashing for foamie construction viewtopic.php?f=55&t=60303
Making a hot wire http://tnttt.com/viewtopic.php?f=55&t=55323
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Re: Beading and Flashing

Postby Postal_Dave » Sat Jul 04, 2020 10:54 am

Having introduced Great Stuff to the foamie world... :lol: Sorry George, I couldn't resist.

If you have to use it, I recommend the Blue can of Great Stuff. It's made for Windows. Because of that, it doesn't expand as forcefully, or as much, as the red or black cans. I usually put down a bead, then wait a minute for it to expand, then start working it. It really takes a while to work it till it stops expanding. Be sure to clamp or weigh down anything you glue with great stuff.

Put down wax paper on any surface you don't want the great stuff to stick to. Make sure the wax paper is smooth and no wrinkles.

Here is a link to a thread I did on great stuff vs loctite foam. http://www.tnttt.com/viewtopic.php?f=55&t=71886

As always, I recommend experimenting before trying something new on your camper.
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Re: Beading and Flashing

Postby ghcoe » Sat Jul 04, 2020 12:25 pm

:thumbsup:
George.

Gorrilla Glue, Great Stuff and Gripper. The three G's of foamie construction.

My build viewtopic.php?t=54099
Working with flashing for foamie construction viewtopic.php?f=55&t=60303
Making a hot wire http://tnttt.com/viewtopic.php?f=55&t=55323
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Re: Beading and Flashing

Postby Shirestone » Fri Aug 14, 2020 9:59 am

Sorry for all the confusion but I just want to make sure I get this right and don't have any water infiltration.
Attached is the end view of the foamie i'm building.
The pink is the foam..the brown is wood and the lighbrown is plywood. Black is the trailer.
my plan is to wrap canvas around the foam and the plywood underneath. The canvas underneath will go about 2"-3" underneath onto the plywood(canvas not shown in image). I am then planning on some hardwood strips under this (not shown) between the plywood and the trailer. This was suggested by ghcoe I believe so as to prevent rubbing of the canvas on the metal frame.
I am then planning on a metal drip edge around the perimeter shown in white. My question is...what is the best method to attached the metal bead or drip edge to the canvas. Im thinking caulking or possibly pl300 and then caulking along the top edge to prevent water from getting in behind. Please keep in mind i am in canada and glidden gripper cannot be obtained here, so that's not an option.
The drip edge i am planning is slightly different in that there will actually be a folded edge to it so that it drips downwards. It's not shown on the image below.
Thanks all for your help.

162921
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Re: Beading and Flashing

Postby ghcoe » Fri Aug 14, 2020 1:14 pm

Shirestone wrote:Sorry for all the confusion but I just want to make sure I get this right and don't have any water infiltration.
Attached is the end view of the foamie i'm building.
The pink is the foam..the brown is wood and the lighbrown is plywood. Black is the trailer.
my plan is to wrap canvas around the foam and the plywood underneath. The canvas underneath will go about 2"-3" underneath onto the plywood(canvas not shown in image). I am then planning on some hardwood strips under this (not shown) between the plywood and the trailer. This was suggested by ghcoe I believe so as to prevent rubbing of the canvas on the metal frame.
I am then planning on a metal drip edge around the perimeter shown in white. My question is...what is the best method to attached the metal bead or drip edge to the canvas. Im thinking caulking or possibly pl300 and then caulking along the top edge to prevent water from getting in behind. Please keep in mind i am in canada and glidden gripper cannot be obtained here, so that's not an option.
The drip edge i am planning is slightly different in that there will actually be a folded edge to it so that it drips downwards. It's not shown on the image below.
Thanks all for your help.

162921


123.jpg
123.jpg (11.09 KiB) Viewed 606 times


I would just use a drywall end piece like this (pictured). I usually use Dap Latex Caulk to seal between the body and the drywall corner bead. Screws to screw it to the bottom of the plywood.

I can see a issue with your planned canvasing of the sides to the floor. If you do not angle the plywood edge to the angle of the incoming wall angle you will get a delamination there. The walls and floor have to be situated so that the canvas can apply grip in shear. With a step like that the canvas will delaminate from the foam as outside forces are applied to it. In fact I venture to say you will have problems as the canvas dries and shrinks.
George.

Gorrilla Glue, Great Stuff and Gripper. The three G's of foamie construction.

My build viewtopic.php?t=54099
Working with flashing for foamie construction viewtopic.php?f=55&t=60303
Making a hot wire http://tnttt.com/viewtopic.php?f=55&t=55323
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