AC schroud cracked

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.
See posts with no answers
Rene T

Rene T

Site Team
Joined
May 20, 2011
Posts
22,412
Location
Farmington NH
About 4 years ago, I removed the shroud off my AC (air conditioner). When I turned it over, I noticed several cracks in the shroud . The color of the shroud is black so it may be ABS.  I made repairs  by scuffing the surface real good and applied a couple layers of fiberglass/resin. It looked good at the time. I took the shroud off today and all the glass was just hanging there ready to completely fall off. What did I do wrong? 
 
Do you recall if you used Polyester, Vinyl Ester or Epoxy Resin?  I'm no expert either, but I'm pretty sure it makes a difference depending upon what the original base material is.  If you were like me some time ago, I just used some Polyester resin available at the local auto parts store and it was a poor choice for repairing my epoxy resin fiberglass boat.
 
Molaker said:
Do you recall if you used Polyester, Vinyl Ester or Epoxy Resin?  I'm no expert either, but I'm pretty sure it makes a difference depending upon what the original base material is.  If you were like me some time ago, I just used some Polyester resin available at the local auto parts store and it was a poor choice for repairing my epoxy resin fiberglass boat.
Click to expand...

I have no idea Tom. If I was back home, I could find the can of resin and let you know.  Maybe I'll go to a auto parts store some day and see what they say. Or a body shop.
 
First; I am thinking that the shroud was plastic, (poly) in which case regular two part epoxy won't work on plastic.
Secondly, a few years back, West Systems came out with "G-flex" epoxy which indeed will adhere to not only plastic but also to wood and metal.

I race Kevlar, fiberglass and poly canoes and kayaks and do all my own repairs and swear by the G-flex for small quick jobs on any of these surfaces. I also wet out fiberglass cloth with it for larger repairs

Jack L
 
NY_Dutch said:
Have you considered replacing the shroud, Rene?

http://www.icondirect.com/categories/RV-Exterior-Parts/Air-Conditioner-Shrouds/
Click to expand...

No I haven't Dutch. The cracks aren't big. They are small and I was just looking to reinforce the shroud on the inside to stop the cracks from expanding. Thanks for the link. I'll keep that in mind. I didn't know they'd be that cheap.
 
Rene T said:
No I haven't Dutch. The cracks aren't big. They are small and I was just looking to reinforce the shroud on the inside to stop the cracks from expanding. Thanks for the link. I'll keep that in mind. I didn't know they'd be that cheap.
Click to expand...

The Icon Direct shrouds are also tougher than OEM shrouds. They make a quality product...
 
Rene T said:
About 4 years ago, I removed the shroud off my AC (air conditioner). When I turned it over, I noticed several cracks in the shroud . The color of the shroud is black so it may be ABS.  I made repairs  by scuffing the surface real good and applied a couple layers of fiberglass/resin. It looked good at the time. I took the shroud off today and all the glass was just hanging there ready to completely fall off. What did I do wrong?
Click to expand...

Just a wild guess on my part but it sounds to me that the products you used for the repair didn't have any UV protection.
I use West systems quite a bit and I'll add something for UV, or use a paint that has protection.

Corky
 
I had a corner/edge dent (hit tree branch) in one of mine, and the shroud was definitely not fiberglass. More like a hard vinyl.  I was able to heat it and literally hammer it back out.

For a crack, you may be able to use plastic welding techniques, which could be as simple as running a soldering iron along the crack. Or try using Acetone or MEK to solvent-weld it.

This article has some suggestions:
https://makezine.com/2017/02/16/plastic-repair/

Or maybe this: http://www.plastex.net/
 
Corky said:
Just a wild guess on my part but it sounds to me that the products you used for the repair didn't have any UV protection.
I use West systems quite a bit and I'll add something for UV, or use a paint that has protection.

Corky
Click to expand...

The repair was done inside the shroud so it never saw the sun.
 
At a previous place of employment we were instructed to clean and prep certain parts that we manufactured with MEK.
After a couple people complained of side effects the MEK was dropped and we started using Acetone.
Understand that this was in the late '70s early '80s, and at that time MEK was on the hazardous material list as a know carcinogenic, but in 2005 it was removed from the list. However I still today avoid it if I can.

As the owner of 3D printing equipment I can tell you that when printing with ABS I use a tip temperature of 245c, just to give you an idea of temperature range you'd need if you decide to try the welding route. Also if you decide to try and weld let me know and I will send some filament to use as I have plenty on hand --- and I have some in black too.

Good luck

Corky 
 
As Gary suggested
Try MEK on it.
If it's ABS, MEK will dissolve it.

Get some ABS material (lego bricks, some filings form a scrap pipe or fitting perhaps....) and dissolve some in a small amount of MEK to make a paste, and fill the crack after stop drilling it and beveling open the edges of the crack.  The MEK will evaporate leaving a solvent weld.

I read an article once a long long time ago in an aviation magazine.  A lot of general aviation planes used ABS sheet as a molded trim panel covering all sorts of interior areas, fairings over door handles, etc...  These have sort of a leather like texture.  The article showed how to use some sort of putty....maybe something like bondo resin, I can't remember.... to mold an undamaged area of the texture.  Then that mold could be used to press into the fresh repair....matching paint and it was as good as new
 
You must log in or register to reply here.

Latest posts

Members online

Total: 1,184 (members: 25, guests: 1,159)

Forum statistics

Threads
131,924
Posts
1,387,548
Members
137,674
Latest member
SPK550
Back
Top Bottom