Remove VHB tape? Holding solar panel down.

Rocketman

Solar Addict
Joined
Sep 27, 2020
Messages
711
Hello everyone

When I put the solar panels on my MotorHome roof, I put one down in an incorrect spot. Now I need to move it.

The piece mounted to my fiberglass MotorHome roof is angled alum 2” wide by 6” long - .187 thick. It has been there for 3 years.

Original prep:
Cleaned the roof w/simple green
Cleaned the area with paint thinner.
Put 3M primer on roof and alum.
Put two 6” strips of VHB tape
Pressed in down well.
Finished with Dicor around to seal moisture out.

Any good ideas on how to remove it?

I figure putty knife and paint thinner to removed the Dicor, then the putty knife to cut the VHB as I run it under the aluminum.

I will be reusing the brackets - Goo Gone to removed the residue?

Any better ideas…???
 

Bob B

Photon Sorcerer
Joined
Sep 21, 2019
Messages
4,365
I've seen some people talk about using something some of the advanced braid type fishing line to cut thru it.

Not sure if it's a better idea.
 

12VoltInstalls

…myself everything do I…
Joined
Jan 18, 2021
Messages
3,972
Location
Vermont
I've seen some people talk about using something some of the advanced braid type fishing line to cut thru it.

Not sure if it's a better idea.
Very thin stranded stainless wire or the dyneema fishing line are what I’d do. Less work, much less chance of damage. Then a razor sharp scraper and heat for the residue.
 

rickst29

Solar Addict
Joined
Mar 27, 2021
Messages
566
Location
Reno, NV
I've done this, on an aluminum roof where I attached my panels without using 3M primer. I would not, and did not use stainless steel "scrapers" or "fishing line" or anything steel on fiberglass or aluminum RV roofing - it will scratch it.

I first used a snap knife, titled up and into each of my mounting brackets (away from the roof, snap knife blades are again steel), to cut the tape within it's foam layer. That released each of my mounting brackets to be cleaned separately. Then, as someone else advised above - I used a hair dryer to assist with heating the tape adhesive and remaining foam on the roof. VHS adhesive becomes much weaker with heat applied.

Pointing the hair dryer towards the working edge of VHB (the 1" width edge, not the length), I used a plastic putty knife - somewhat sharpened, but softer than my aluminum roof (unable to scratch it). Peeling the VHB remainder up from a corner, using the knife very slowly, until I peeled the entire inch of width. For me, this worked best at an angle - but my RV roof has some curvature. It was slow going, about 10 minutes per 5-inch bracket. A couple of "failures to pull" were pretty easy to resolve at the end, attacking those spots from all 4 sides.

Your piece is twice as wide as my brackets bases were, with more time needed to remove it from the roof. Maybe a steak knife (longer than my snap knife blades) can do the job, with the sharp edge tilted up and into the aluminum (away from the fiberglass. Remember -the goal of that first step to simply remove the bracket, and not to remove the VHB tape. The tape itself is removed afterwards, while you can directly warm it using the focused hair dryer.

I've no idea how primer may interfere with my process. Good luck - use a hair dryer, and take your time.
 

Rocketman

Solar Addict
Joined
Sep 27, 2020
Messages
711
Thank you everyone for the better ideas!

That’s what I love about this place!
 

12VoltInstalls

…myself everything do I…
Joined
Jan 18, 2021
Messages
3,972
Location
Vermont
I've done this, on an aluminum roof where I attached my panels without using 3M primer. I would not, and did not use stainless steel "scrapers" or "fishing line" or anything steel on fiberglass or aluminum RV roofing - it will scratch
Professionally, I have removed tapes, ID panels, and urethane-adhered brackets and other items from boats and trailer roofs. Glass removal to brackets.
The cable never touches the surface the tape is mounted to and I have not experienced any inductive scratching, either, using stainless cable.
Same for sharpened scrapers: they get used to cut the vhb not as a scraper against the substrate.
with the sharp edge tilted up and into the aluminum (away from the fiberglass. Remember -the goal of that first step to simply remove the bracket, and not to remove the VHB tape.
The plastic putty knife trick works well in some circumstances. A steak knife (?!!) can neither cut flush nor upwards due to handle; it can’t get flush.

A razor-sharpened scraper knife with its 15* bend cuts the caulking or vhb UPWARDS away from the substrate with relatively little force. The stranded wire cable trick is used by people in body shops to remove certain adhered things. It’s not a “hack” it’s a method
 

jberger

Solar Addict
Joined
Jun 1, 2021
Messages
272
I've done it with a snap knife, carpet hook and also a sharpened painters tool, next time I will try an oscillating multitool instead. Heat is a huge help, as VHB strength declines with heat.
If you tape off the outside of bracket, it helps prevent those surface scratches too.
 
Top