Underbelly tape

tfgd21bhe

Senior Member
Joined
Aug 18, 2019
Posts
198
A couple weeks ago I repaired a lousy job the dealer did taping up the underbelly after they worked on the black tank dump valve.

I cleaned the coroplast with a rag and mineral spirits and then again with another rag and alcohol. I used this

https://www.amazon.com/gp/product/B00V974DKG/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8&psc=1

and on a smaller slit done for my disc brake conversion I used gorilla tape.

I came back to the trailer a week later and the both the gorilla tape and the underbelly tape had completely fallen off.

What's the secret to getting tape to stick to the underbelly.
 
I havent personally used it, but others on this forum have stated the tape they use on mobile home trailers works well. If you search the forum or internet, you might be able to find it. I'm talking about single and double wide trailers when I say mobile home.

Sent from my SM-G950U using Tapatalk
 
I had to cut into the coroplast for a repair out on the road. I always carry Eternabond tape in my repair kit, so that is what I used to join the coroplast back together. Thick tape, but it was still working when I sold it many miles later.
 
I think things might have gone south with the mineral spirits. It's almost impossible to get all of it off - even with alcohol. I've cleaned the Coroplast with just alcohol and the mobile home underbelly repair tape was still holding well three years later.

Rob
 
If Gorilla tape didn't hold, two things are likely - you used on the 2" versus the wide and your patched area has too much flex. Due to COVID-19, the wider version hasn't been around much. Anyway, first thing, you have to mend the cut sides first in mechanical fashion. I normally use thin aluminum sheet metal as I always have a coil around. A 3- or 4-inch strip behind the coroplast that you can screw the coroplast too. I use self-piercing, truss head screws. For small cuts, you can often get away with stitching it up with zip ties. Just don't poke the holes for them closer than about 1-1/4" from the edge of the coroplast. When you clean coroplast before sealing, NEVER use a petroleum distillate! That is the worst advise out there! If you know what coroplast is made from - no bueno. If you know what is in the off the shelf tape adhesives - no bueno. Get a citrus-based tub of cleaning wipes from the hardware or auto store and scrub the area or use some Purple Power and lint free rag. You can use alcohol after if you'd like, or just wipe with a clean cloth and water to remove the surfactants. If you can't get Gorilla tape wide, seek out at least 4" wide mobile home underbelly repair tape, which has a very, very sticky adhesive such that it's a peel off liner style. If you can't find that, go to a genuine contractor supply and ask for the stickiest tape they have for foundation waterproofing. If it has an incerted black and red triangle logo, it's one of my tapes. After you apply it, and firmly seat the tape to the coroplast surfaces, use a heat gun on low or hair dryer on high and just warm the tape to fully activate the adhesive. The essential takeaway here is that no tape will hold if the coroplast can widely flex as air currents travel along it when in tow. Think of it as a whipping action against the tape.
 
I think things might have gone south with the mineral spirits. It's almost impossible to get all of it off - even with alcohol. I've cleaned the Coroplast with just alcohol and the mobile home underbelly repair tape was still holding well three years later.

Rob

Mineral spirits may have attacked the coroplast and caused adherence problems, but pure mineral spirits will evaporate with no residue left behind. Many years of experience
working with it.
 
I think this is the brand I used:
https://www.amazon.com/Surface-Shie...b25e6&pd_rd_wg=m9q20&pd_rd_i=B002SSGAZG&psc=1

It is really sticky. I had to tape my underbelly on the way to Colorado and lasted probably 3,000 miles until I got home. I did have to fix a few times. Tape was still there, but wind got under the coroplast. Finally went full sheets side-to-side and didn't have an issue after that.

This is what I used and recommend. Gorilla tape (the 3" size or maybe it was the 4") didn't hold. I use alcohol to clean the area(s) first.
 
I use tie wraps to secure the flaps. I space them about every three inches and they look like stitches..
 
If Gorilla tape didn't hold, two things are likely - you used on the 2" versus the wide and your patched area has too much flex. Due to COVID-19, the wider version hasn't been around much. Anyway, first thing, you have to mend the cut sides first in mechanical fashion. I normally use thin aluminum sheet metal as I always have a coil around. A 3- or 4-inch strip behind the coroplast that you can screw the coroplast too. I use self-piercing, truss head screws. For small cuts, you can often get away with stitching it up with zip ties. Just don't poke the holes for them closer than about 1-1/4" from the edge of the coroplast. When you clean coroplast before sealing, NEVER use a petroleum distillate! That is the worst advise out there! If you know what coroplast is made from - no bueno. If you know what is in the off the shelf tape adhesives - no bueno. Get a citrus-based tub of cleaning wipes from the hardware or auto store and scrub the area or use some Purple Power and lint free rag. You can use alcohol after if you'd like, or just wipe with a clean cloth and water to remove the surfactants. If you can't get Gorilla tape wide, seek out at least 4" wide mobile home underbelly repair tape, which has a very, very sticky adhesive such that it's a peel off liner style. If you can't find that, go to a genuine contractor supply and ask for the stickiest tape they have for foundation waterproofing. If it has an incerted black and red triangle logo, it's one of my tapes. After you apply it, and firmly seat the tape to the coroplast surfaces, use a heat gun on low or hair dryer on high and just warm the tape to fully activate the adhesive. The essential takeaway here is that no tape will hold if the coroplast can widely flex as air currents travel along it when in tow. Think of it as a whipping action against the tape.

Flex of the coroplast slit couldn't have been an issue as the trailer was parked and never moved between the time of the tape application and when it fell off by itself. The tape I used for the main repair was indeed 4" wide mobile home tape.

Thanks for the replies. I'll guess I'll buy some more tape and clean again with alcohol and try again.
 
Flex of the coroplast slit couldn't have been an issue as the trailer was parked and never moved between the time of the tape application and when it fell off by itself. The tape I used for the main repair was indeed 4" wide mobile home tape.

Thanks for the replies. I'll guess I'll buy some more tape and clean again with alcohol and try again.

Also do your best to avoid taping it on a humid day.

I can only speculate some combination of your cleaning with mineral spirits and stale tapes. The all-weather Gorilla Tape is a butyl tape, which is the general kind of tape that sticks "best" to polyolefins. I'm not familiar with that brand of mobile home tape, but the better tapes are polyethylene or polypropylene slit-film scrim with butyl-based adhesive.
 
There was mention of a different type of coroplast being put on a 2021 Solitude and when asked, GD said to use eternabond on it.
The coroplast had dimpled circular patterns on the surface.
 
Underbelly Tape

A couple weeks ago I repaired a lousy job the dealer did taping up the underbelly after they worked on the black tank dump valve.

I cleaned the coroplast with a rag and mineral spirits and then again with another rag and alcohol. I used this

https://www.amazon.com/gp/product/B00V974DKG/ref=ppx_yo_dt_b_search_asin_image?ie=UTF8&psc=1

and on a smaller slit done for my disc brake conversion I used gorilla tape.

I came back to the trailer a week later and the both the gorilla tape and the underbelly tape had completely fallen off.

What's the secret to getting tape to stick to the underbelly.

I’ve had success using RV roof repair and flex-all repair tapes. Both are several inches wide and have excellent cohesion to a multitude of materials including the corrugated underbelly covering underneath my Solitude.

Good luck.
 
Although I named flex-all as the brand name for a tape I’ve used, the correct brand name is flex seal. My bad.
 
Absolutely the best tape for this is the ZIP tape used in residential & commercial wall construction. Other than ZIP being printed every 12” on the tape, I have no complaints about it’s durability and adhesion. I repaired the underbelly on a friends travel trailer 7 years ago and it’s still in perfect condition. I wouldn’t use it where it would be exposed to the sun for an extended period of time. UV rays will do a number on it in 10-12 months.
 
Had the same problem with a dealer's tape repair job coming undone after they made an incision to correct a tank valve issue. Considering all the road contamination and in my case, diesel exhaust residue, I thoroughly cleaned the surface with acetone. Surprisingly, the dealer's tape, re-used, stuck nicely, but I reinforced it with Gorilla tape. After a conversation with the dealership, I understand they use acetone now too. After a subsequent repair there following a recall notice, the dealer's initial repair on that incision is holding up just fine.
 
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I think things might have gone south with the mineral spirits. It's almost impossible to get all of it off - even with alcohol. I've cleaned the Coroplast with just alcohol and the mobile home underbelly repair tape was still holding well three years later.

Rob


I used rubbing alcohol too to clean (I believe that is what they recommend) - has held very well.
 
In 2018 I had to fix a couple of "openings" in the Coroplast under our Solitude. Lowes sell the same material (white only) in 3 x 4 foot sheets, more or less. To patch a hole when I relocated my battery vent I cut a square piece and after cleaning I used shower and bath silicone to stick it on, then used furnace duct screws (1/4 inch x 1/2 hex head) to hold it all together until the silicone set. Nobody can see it down there anyway.
I later closed a seam using bigger pieces. Not one of these repairs has failed...yet!
 
I had to access the underside of a different brand of trailer a few years ago. I cut a three sided opening leaving the fourth side as a natural hinge in the colorplast. Then used some scraps of treated fence boards to create a frame around the opening so that I could screw the flap shut.

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