Adding Solar Panels

[Bigfoot Mike]

I would like some ideas on how to attach Solar Panels to the roof of my Bigfoot without making holes in the Fiberglass.

Any ideas?
What would you recommend?

1. 3M something?
2. Epoxy?
3. Bedding compound?

If you’ve done it, please post photos. Thanks for your feed back and ideas.

[Lisa H.]

I'm glad you posted this question since I have the same dilemma. I got my new 120 watt panel last month. Does anyone have any thoughts about about fiberglassing a wood frame onto the roof and then screwing the solar panel frame into it? Of course, one would need to put butyl tape under the solar panel frame so there would not be any water intrusion into the wood.

[Raya]

If you're going to 'glass something onto the roof, you might consider using pre-made fiberglass angles, or cutting a profile from pre-made fiberglass board*. Then you wouldn't have any rot worries, like you would with wood.

On the other hand, in terms of how intrusive the project is, this would be moreso than holes/machine screws because of the fiberglass tabbing extending outwards. But.. no holes.

I wouldn't think that bedding compound would hold without fasteners; likewise I would think epoxy would be a risk without fiberglass reinforcement (i.e. cloth or etc.).

I wonder if VHB tape would work? Part of me thinks yes, but another part shudders at the thought of a solar panel bouncing down the highway.

I guess if it were me, I would use fiberglass/tabbing if I knew I was going to be painting the trailer, and machine screws/bedding if not (although I know you're asking about no-hole solutions).

*available, for example, from McMaster Carr at www.mcmaster.com Just search on "fiberglass"

[Anne3358]

I would like some ideas on how to attach Solar Panels to the roof of my Bigfoot without making holes in the Fiberglass.

Any ideas?
What would you recommend?

1. 3M something?
2. Epoxy?
3. Bedding compound?

If you’ve done it, please post photos. Thanks for your feed back and ideas.

Hi Mike;

Here is a link I saved. It might be of help:

Solar install with VHB tape, no drilling, but one big hole

[Raya]

Great info on the VHB tape. Looks like it might be a winner. Thanks for the link.

Raya

[Lisa H.]

Great idea on the VHB tape. I had never heard of it before so I googled it and found this video from the Discovery Channel describing it's strength and uses. Very interesting stuff!

VHB Tape- very sticky, strong stuff

Good suggestion!

[Greg A]

I've read a number of posts on installing solar panels on the roof with the VHB Tape and there hasn't been any mention of issues arising.

[Anne3358]

Great info on the VHB tape. Looks like it might be a winner. Thanks for the link.

Raya

We purchased the tape for our Twin Bed Mod. It is expensive (for tape .... about $65 with freight) but it is very strong and lots of it.

[Gina D.]

A word of caution on VHB tape...

having used it in mass qtys in the land of amplifier manufacturing.. I can tell you that it can fail in high heat situations if not applied with the utmost care and skill. This was the FAA approved stuff, not your average off the shelf stuff.

Like everything that sticks stuff to other stuff.. its all in the prep.

I considered using it when I was thinking of mounting my panels to my roof, but I couldn't get past the failures I have seen (And repaired). The roof gets mighty toasty... and I just do not know all the characteristics of fiberglass well enough to trust myself to do proper prep.

[Raya]

Very good point, Gina. In the boating industry, it's all about prep, and like you I've seen a lot of failures and re-repairs of various jobs (usually paint and fiberglass) due to poor prep work.

I don't know enough about the Very High Bond tape to advise for or against it, but I can at least say a couple of things about prepping gelcoated fiberglass for painting (another time when you want things to stick...).

The main thing that people skip over is to remove the mold-release wax. This is "mold" as in the thing your trailer was built in to give it shape, not as in the yucky stuff that grows in damp corners. It seems unbelievable, but yes, the wax remains on a 25-year-old fiberglass boat that's been out in the air and water all that time. So I'm sure it's still there on the trailer, too.

To remove it you use a solvent. We typically use Interlux 202 (they number all their solvents). I think it's a highly purified acetone, but I'm not positive. The trick is to wipe the surface with a 202-soaked rag or towel (we used special type paper towels), and then immediately wipe with a clean towel. It's easy to recontaminate if you don't always use a clean section of towel for both operations. I mean, not that it's brain surgery, but you have to be tidy or you just smear the wax around.

Once you have the wax removed (and it's important not to reverse these steps, or you'll just "grind it in," then you sand or scuff the surface to whatever the final product recommends (for example, a primer might want you to use 180 grit sandpaper). I'm not sure if the tape would want a smooth or roughened surface, but even if it requested smooth, I'd be tempted to sand with something like 600 or 1000 grit to get a really smooth and level surface. But of course I'd read the tape manufacturer's instructions on that.

Again, this isn't to recommend or warn against the tape, but is just a bit of prep info.

If one were to use the tape, I like the idea that came about later in that Casita thread to mount only an initial bracket, and then mount the panel to that bracket with a more remove-and-replaceable fastener.

I would like to add a panel, as I got hooked on the "free" and silent power when living on boats, but I can't decide whether to "fit and forget" on the roof, or to have a portable panel. I usually strive to park in the shade (which is not really an option when anchoring a boat )

I like the idea of the new, super-thin panels that are "stick on" panels - that's pretty neat. I'm not sure if they're ready for prime time though. In the old days (early 2000's), the flexible type panels had the advantage of putting out power even when partially shaded, but of not putting out as much power ever; while the hard panels put out much more power, but essentially quit altogether the minute even a thin line shaded a section of them. I haven't done my current research to see how that's changing, if it is. So far, I've only been "driveway camping" where there is a handy AC outlet nearby.

Raya

[kevin61]

Here is one way to do it.

http://www.youtube.com/watch?v=akufm_DarLY...feature=channel

After having put about 4000 km on the trailer this summer I have had no problems with leaks or panels falling off.

I plan to fix another trailer and will simplify the mounting system using 4 shorter pieces of extruded aluminum (one for each corner of the panel) and fibreglass these directly to the roof without using bolts. This will eliminate the one mount which presently sits broadside to the wind (creating extra stress on the mounting system) and will allow for a free flow of air above, below and around the panels. In this case an air deflector should not be required in front of the panels.

Please note this method works well if your trailer is painted as it is easier to cover your work with paint as opposed to restoring the gelcoat. (gelcoat can be done, it just takes more finesse)

Lisa, the same idea could be applied to your plywood frame suggestion. Here is how I added a rooftop spacer for my fantastic fan using plywood.

http://www.youtube.com/watch?v=qlYDaU84XWw...feature=channel

Do not completely enclose the underside of the panel as solar panels do not work well if hot. They need good air circulation all around to keep them cool.

[Bigfoot Mike]

Hi Mike;

Here is a link I saved. It might be of help:

Solar install with VHB tape, no drilling, but one big hole

Thanks, This looks like what I would like to use. ...off to study, test.

[Bigfoot Mike]

clipped...
To remove it you use a solvent. We typically use Interlux 202 (they number all their solvents). I think it's a highly purified acetone, but I'm not positive. The trick is to wipe the surface with a 202-soaked rag or towel (we used special type paper towels), and then immediately wipe with a clean towel. It's easy to recontaminate if you don't always use a clean section of towel for both operations. I mean, not that it's brain surgery, but you have to be tidy or you just smear the wax around.
etc.etc.etc.

Raya

Good stuff. Thanks for taking the time to be specific.

[Greg A]

Found some of the posts, Solar VHB
and another Solar VHB

Bunch of them out there.

[Bigfoot Mike]

Found some of the posts, Solar VHB

Thanks Greg. This is just what I want to do.

[Chester Taje]

Mike----I am really glad you asked that question. Lots of great info in this thread.

[Morgan]

Thanks Greg. This is just what I want to do.

Mike,

The best place I've found for buying VHB tape is McMaster-Carr. The have a huge selection and you can buy smaller rolls.

Good luck.

[Kevin K]

http://www.itapestore.com/index.asp?PageAc...ustom&ID=19




Try this stuff.

[Morgan]

Try this stuff.

<span style="font-size:12pt;line-height:100%">Velcro?</span>

[Bigfoot Mike]

Mike,

The best place I've found for buying VHB tape is McMaster-Carr. The have a huge selection and you can buy smaller rolls.

Good luck.

Morgan, Would you feel comfortable using VHB tape to hold your solar panels on?