Teardrops n Tiny Travel Trailers

Hey Folks,

I am coming down the final stretch on my squaredrop build and after spending all week painting the exterior I have had a bit of snafu and need to make some repairs.

Yesterday I applied 2 coats of Herculiner (4 hours apart) as an accent on my corners/front of my camper and to give some additional abrasion resistance. After letting the Herculiner cure overnight ~14 hours I went to remove the masking tape and discovered a significant portion of the Herculiner/paint could be peeled off about as easily as the masking tape.

From the photos below you can see most of the bonding failure actually occurred in the paint. The surface of the epoxy was noticeably tacky with wet paint. There are other places where the paint is 100% intact/cured and the Herculiner failed to bond. > 50% of the Herculiner & paint is perfectly bonded and would require me to break out the carbide scraper to remove it.

My questions are as follows: 1) Why did this happen? 2) How do I repair this? 3) I have noticed the frog tape I used for masking left a pink hue behind. Is this normal? How should I remove it?

To give background on my build procedure & materials:
- I applied the fiberglass cloth & raka epoxy > 2 weeks ago.
- Corners received the the last coat of epoxy > 8 days before first coat of paint.
- After a week of curing epoxy I sanded it all down with 100 grit & removed dust with dam shop rags
- The next evening I began 3 consecutive days of painting. I rolled on (3) coats of Rustoleum Professional Enamel. Waiting 24 hours between coats.
- Prior to the Herculiner I roughed up the paint with the provided abrasive pad. For redundancy I also applied some rustoleum universal primer I had on hand but it only did 1.5 coats on the areas to be covered in bedliner.
- Like most places in the US it has been very hot the last 3 weeks. Peaks have been ~100 degrees F. Humidity in the 40-60% range. Epoxy was mostly applied in mornings at < 90 deg F. Paint was applied > 1 week later in evenings at < 80 deg F.

I am a bit confused as to how this happened. The herculiner failing to bond to the paint I can chalk up to insufficient surface prep but as far as the paint failure goes I am guessing the cure must have screwed up by the heat the last few days?

My plan as of now is to sand down the problematic areas. Clean the area, apply 2 coats of primer. A couple coats of enamel. Then do (2) coats of Herculiner. Is this prudent or is there is reason to believe the rest of my paint job is compromised? Any way to test other than scraping edge with carbide scraper to test hardness?

Any guidance on how to remove the bedliner without damaging the fiberglass/epoxy would be appreciated.

Thanks in advance.

Additional photos

My thoughts immediately go to amine blush. I'm not specifically familiar with the Raka brand, and you didn't mention if you used the non-blushing low amine variety. Either way, I would have scrubbed with water and a worn out greenie pad before sanding for texture. Any amine at all if you sand without washing you risk pushing the amine into the sanding scratches making it less likely to wash off. I would also have allowed a much longer curing time for the epoxy, as it can continue curing, and pushing amine out much longer than the working time cure (although heat does accelerate the cure). IIRC, amine can be worse in more humid environments, too.

KCStudly wrote:My thoughts immediately go to amine blush. I'm not specifically familiar with the Raka brand, and you didn't mention if you used the non-blushing low amine variety. Either way, I would have scrubbed with water and a worn out greenie pad before sanding for texture. Any amine at all if you sand without washing you risk pushing the amine into the sanding scratches making it less likely to wash off. I would also have allowed a much longer curing time for the epoxy, as it can continue curing, and pushing amine out much longer than the working time cure (although heat does accelerate the cure). IIRC, amine can be worse in more humid environments, too.

+1 on amine blush for the paint failing to stick to the epoxy. Even though I often use Raka Non-blushing epoxy, I still scrub down the surface with hot water and soap.

Another problem could have been the paint was not completely cured. If you can still smell solvent even after it's "dry" it's not really dry. Putting the bedliner over paint that's still outgassing solvent dramatically slows the outgassing of solvent.

The bedliner may not have been compatible with the paint. Would the bedliner stick better to bare epoxy?

I'm curious about how well the paint is adhering to the non-bedliner areas now that it's had more time to dry. Maybe you could test a few inconspicuous areas.

If what's left of the bedliner is now tightly adhered, I'd scrub the bare areas and mask around them. I'd try to fill in the bare areas and then give everything one more coat and hope for the best. I'm assuming that the bedliner will stick to bare epoxy.

Then touch up the paint.

Thanks for the input guys. No blush just poor cure in the Bedliner and paint. Managed to sand it down and reapply more slowly being sure to strip the masking tape right away. Turned out great.

That's great! Though I'm sure sanding that off was a pain.

Nice looking trailer!

Nice looking TD. Question: Did you add the racks to your TD or were they there when you got it..? Interested to know what brand they are and where they're available for purchase. Gives me thoughts of possibly adding them to my TD..

cdnred wrote:Nice looking TD. Question: Did you add the racks to your TD or were they there when you got it..? Interested to know what brand they are and where they're available for purchase. Gives me thoughts of possibly adding them to my TD..

I got my doors and rack from Sherpa Trailers based out of Libby, MT. Pretty out of the way for most folks. Highly recommend stopping by if you are in the PNW though. Super friendly folks and basically gave them to me at cost.

I like it
MT

Enginerd99 wrote:I got my doors and rack from Sherpa Trailers based out of Libby, MT. Pretty out of the way for most folks. Highly recommend stopping by if you are in the PNW though. Super friendly folks and basically gave them to me at cost.

I'm from Ontario, Canada so that's a bit of a drive for me but maybe next summer I'll take an extended trip. I used to work in Richland, Washington for 5 years so I'm familiar with the area. I'm assuming you bought them and installed them yourself..? How did the install go simply enough, didn't take too long..? I like how the mount off the side as opposed to on the top, less chance for leaking. Are there options that go with the rack like for a cargo carrier or boat..? What's the brand name on the rack, I might be able to find them local to me..? Looks sweet and affords you lots of extra storage space when traveling..