Using VHB tape for Solar

[MyronL]

I am planning to install a 190 watt solar panel on my roof. It’s big, and weighs 26 pounds, and I want the option of tilting it when warranted by the sun. I am building a frame for it. The plan was to attach this frame using 3M USB tape. 3M claims their #4950 double sided tape will replace a bolt.

I did not want to drill any holes for holding bolts in my fiberglass roof. Now, after doing a test just to see what kind of road vibration the solar unit will be subjected to, my opinion has changed. I don’t think reliance on any adhesive, no matter what 3M claims, is wise.

Click on my UTube video here, for your thoughts on this.

https://youtu.be/X8tyU-2wqqo

[Darwin Maring]

It is about making sure it does not come off when driving. It could cause an accident and kill someone.

[Larry C Hanson]

Hello,

Great that you don't want to put holes in the roof.

Why not use a portable panel? After all, on hot days it is always
better to park in the shade where a roof mounted panel hardly
works. A portable panel at the end of a cord allows you to put
the panel in the sun at a proper angle. If you are around camp
during the day the panel can be repositioned for more solar gain.
Also, one does not have to climb a ladder to mess with the panel
on the roof.

Good Luck,

Uncle Larry

[Glenn Baglo]

Originally Posted by MyronL

Click on my UTube video here, for your thoughts on this.

https://youtu.be/X8tyU-2wqqo

That's the camera that is vibrating, not the roof so much.

[WaltP]

You might think of a compromise like I used when mounting a barn quilt recently.
I basically mounted it with VSB tape but added a single screw as an emergency backup. I know mounting it on a moving platform is a bit more challenging, but the principle should still work, although I would check on it it regularly.
Walt

[WaltP]

Glenn's video does provide some reassurance, although I would still back up the tape somehow.

Walt

[Stan K]

If you use some 3M Adhesion promoter it will NEVER come loose. Make sure you get it right the first time as it's on for good. No second chances.

[MyronL]

I do carry 200 watts of portable solar but now I want more power, plus want solar that is always up there working. That GoPro might be contributing to the recorded vibration but hardly enough for me to ignore the obvious. Why take a chance? Bolt we must!

Another thing is my trailer roof is not straight and flat, and I know of at least one trailer like mine that had it's factory taped on panel ripped off in a severe crosswind that ripped off the bleeping gelcoat. I really hate drilling any holes in my roof, ......but....!!

[Nigel G]

Myron,

I used 3M VHB tape to mount a 160-watt solar panel on a 2010 R-Pod that I had many years ago. I had it for 3-years and on the day that I sold it, it was still there and just as strong as the day I installed it. I am still stunned to this day that it did so well going 70 MPH on the freeway with all of the vibration and wind resistance. You just have to make sure that the mounting surface is completely clean with thorough use of rubbing alcohol or some other type of fiberglass friendly solvent. Keep in mind that VHB tape is what most auto manufacturers use to adhere logos and a variety of other parts to automobiles.

Hope this helps, I have no reservations using it for a variety of items!

[WaltP]

For a surface that is not flat, you might want to look at the flexible solar panels. The tape might even be preferable there.

Walt

[MyronL]

I looked at flexibles but rejected them for two reasons.

First, yes, light, super thin, but although many are happy with theirs I read the overall track record for longevity when compared to the more robustly built framed ones is dismal.
Second, they don't make one larger than 100w that fits, and I do not want more than one panel on my roof. Too many exposed wires. Plus, you can't tilt one toward the sun.

GBags - just rewatched my vibration video and noticed the horizon wasn't vibrating. Think a vibrating camera would vibrate everything in the shot, no?

[Flydog]

I'm glad you brought this up because i have the same misgivings about VHB for this application. On my previous 5er I used EPDM rivnuts and stainless steel machine screws then went over it all with Dicor. The EPDM rivnuts are self sealing.
This time however, I think I'll only use one rivnut per attachment point and probable the smallest diameter rivnut that will work.
https://www.boltdepot.com/Product-De...content=Rivets

[WaltP]

That link doesn't work on my phone.
I'll try it later on my laptop.

Walt

[CASITA BANANA]

I have 4x100 watt panels on my Casita that have been there for years held on with no holes and VHB tape. I've been in 60 mph head winds at 60 mph. I think that's a good enough test. To handle the curves I used one layer on the inside and two layers on the outside of the curves. Then I sealed it all with caulk so water wouldn't compromise the tape and it's all stayed put for several years. Camping mostly in the southwest I really haven't worried about pointing the panels at the sun; i just used more panels laid flat ... overbuilt so to speak.

[Jane P.]

Originally Posted by WaltP

That link doesn't work on my phone.
I'll try it later on my laptop.

Walt

The problems lies with my post. Can’t edit it for some reason. Turned my iPad off, then logged on again. Have no idea what’s wrong - maybe I should have paid my Forum dues ...

[tractors1]

Originally Posted by MyronL

I am planning to install a 190 watt solar panel on my roof. It’s big, and weighs 26 pounds, and I want the option of tilting it when warranted by the sun. I am building a frame for it. The plan was to attach this frame using 3M USB tape. 3M claims their #4950 double sided tape will replace a bolt.

I did not want to drill any holes for holding bolts in my fiberglass roof. Now, after doing a test just to see what kind of road vibration the solar unit will be subjected to, my opinion has changed. I don’t think reliance on any adhesive, no matter what 3M claims, is wise.

Click on my UTube video here, for your thoughts on this.

https://youtu.be/X8tyU-2wqqo

Earlier Escapes used Aluminum mounts that were epoxied to the roof to hold the solar panels. When caught in a crosswind, a few lost their solar panels as the gelcoat separated from the fiberglass - not the adhesive. Escape sent retrofit kits to all owners that included bolts to fasten them to the roof after drilling a hole. Choice of method is yours!

[Jane P.]

Here’s another drill-less video by Will Prowse

https://m.youtube.com/watch?v=qGuFYoS5nT8

[Jane P.]

I’m in the process of installing my solar system. I ordered drill-less mounts & “traditional” Z-mounts. Now i’m need to decide which method i’m gonna use. To that end, as well as another technical question I contacted Bigfoot Inc. Bigfoot screws holes into the roof for their solar installs. They avoid drill-less mounts for safety sake.

As much as I hate the idea of putting holes into the fiberglass, I am moving that direction. And my 100w panels weight under lbs.

I believe Rich Solar sells mounts that tilt. If your panel fits, you can attach the tilting system & the panel into that. You’ll be drilling holes, but will minimize them.

https://richsolar.com/collections/mounts

[fofobraselio]

Hey,
I've installed 2 solar panels on the curved roof of my boler.



I did not use flexible for the reasons you talked about.



I had a portable panel before but it's quite nice now having them on the roof permanently and always absorbing sun even while driving.


I didn't want to drill right into the roof so glassed in some wood for them to mount too. I used vhb tape and screwed them in for added safety and always give them a quick test before driving to make sure they are well fastened


Link here



https://www.fiberglassrv.com/forums/...0-a-93225.html