FWC Single Sheet Roof "Tin Canning"...Why?

[Wallowa]

The dimples are hail..
The diagonal lines, no clue..
parts of my roof are probably 3/4 inch away from the roof studs (I can push it down and feel when it hits the studs)

Yes...I can also push my top sheet down over the roof struts....definitely not attached...'16 Hawk

 

[ski3pin]

Here is what mine looks like, wish I could post of video as I can push it down and it bounces back.. clearly not connected to much of anything anymore..

2013 Grandby

What does a new roof cost out of curiosity ?

Yes...I can also push my top sheet down over the roof struts....definitely not attached...'16 Hawk

So this is not the thin roof sheet flexing but an obvious failure of the adhesive. What is length of the warranty?

 

[BBZ]

So this is not the thin roof sheet flexing but an obvious failure of the adhesive. What is length of the warranty?

No Clue and probably does not apply to me as I am not the first owner and the camper is 10 years old.

I appreciate Stan coming to this forum and offering insight, but it really does seem like the 2 sided tape is not as strong as they hoped for as there seem to be quite a few of us with this problem.

I would prefer to not get a new roof, but curious to keep hearing suggestion on how to minimize the noise so that I can sleep when its windy.. (ear plugs don't work for me as its just too loud).

 

[kmcintyre]

No Clue and probably does not apply to me as I am not the first owner and the camper is 10 years old.

I appreciate Stan coming to this forum and offering insight, but it really does seem like the 2 sided tape is not as strong as they hoped for as there seem to be quite a few of us with this problem.

I would prefer to not get a new roof, but curious to keep hearing suggestion on how to minimize the noise so that I can sleep when its windy.. (ear plugs don't work for me as its just too loud).

Even if it was covered under warantee, they'd have to remove the whole roof (maybe) and it get on the 'work bench'. Then remove the top layer and reapply either the tape or some other adhesive and then re-install. Could be at least a day's worth of work. I'm also not sure if they vinyl would "survive".

 

[ckent323]

If VHB tape is used by FWC to adhere the roof skin to the roof struts (rafters) I wonder which one, there are literally dozens of VHB tapes. They are designed for many specific applications. I have used a couple of different VHB tapes and found the adhesive very strong when the tape was applied correctly.

https://www.3m.com/3M/en_US/p/c/tapes/b/vhb/

I also cannot help but wonder if the temperature and humidity range the camper roof is subject to, and thus the tape, might be part of the issue by causing the tape adhesive for the particular tape used to fail either cohesively or adhesively over time and temperature/humidity extremes. There is a range of possible failure mechanisms including inadequate surface preparation, faulty material lots, etc that could be the root cause.

A full diagnosis would require disassembly and inspection by someone knowledgeable of structural adhesive tapes. Hopefully, FWC (or 3M advisors) performed lifecycle simulations over a wide range of temperatures and humidity with a roof panel adhered to roof struts before the engineering team employed VHB tape to adhere the one piece roof to the roof struts.

I am familiar with product development and it is not uncommon for design changes to experience unexpected failures after the product has been put in use even after structural/thermal modeling and scale model simulations appear to show success during the development phase. Indeed, lifecycle simulations are often not performed because of the time and cost involved. In fast paced development and analysis moving quickly into production environment that commercial products exist in, unexpected failures of new designs, even years later after real world vibration, temperature, and humidity cycling are always a risk.

It seems like a number of campers have experienced this problem. It is not clear from reading on this forum if it is just a few campers or a lot of campers or even campers of a particular model or range of years.

I encourage and hope everyone who experiences this problem (original owner or not) reports it to FWC. Hopefully FWC will collect that data by model and model year which might aid them in tracking down the issue, particularly if it is related to something like aging of the tape or particular year or model of camper. If it is a warranty issue that results in repair (and I have no idea if that is the case) then I would expect that FWC does reasonable investigations during repair to understand the root cause of the problem and if needed come up with a solution. The more people that report the issue the more likely FWC will understand the problem and a way to remedy it.

 

[pvstoy]

Expansion and contraction of different metals with a tape surface between that could be shearing is one thought that comes to mind.

The roof truss beams may not move much but a thin-ish one peice aluminum sheet that is captured all around the edge, if it would expand and contract with heat and cold would ripple and distort wherever it could. Results could be shearing breaking the VHB tape over time no matter how good the bond might be. Time is against it.

Instead of wide flat aluminum straps to add to roof, thinner lighter aluminum angle could be used easily and found at a home improvement store.

 

[ckent323]

Pvstoy,

Good thought. However, I believe that the frame and the roof are both Aluminum and so should have similar thermal expansion characteristics (even if different alloys).

Given that they are both Aluminum the tape should experience minimal shear stresses unless there is some mechanism that constrains the frame or roof from expanding or contracting together, but if that were the case I would expect to see failures related to that in campers with the roof attached to the rafters (struts) with fasteners.

 

[Wallowa]

Regardless of the "mechanism of injury'....the method of attaching the top sheet to the struts/rafters/top frame failed; VHB has not held. If the top sheet was truly held down, the bubbling and tin canning would not occur.

 

[Jon R]

The insulation in the roof of my 2021 Grandby is definitely not bonded to the roof sheet metal. I can feel it moving when I gently press the head liner.

Edit 5/30: Now I’m not so sure about this statement. The insulation may have been moving with the metal. See my later post.

 

[kmcintyre]

I was kind of wondering this same thing. I would suspect the camper would have to go back to the factory and it'd probably take the better part of a day and if they have to remove the top and roof I wonder about the vinyl?

I think I'll probably video mine next time it's doing it so I'll have a record and then send it to Stan or ? so they know about it.

I still believe having the 1 piece roof is superior to having a roof with screws (maintence on those roofs took a lot of work to keep them leak proof).

Kevin

I have a 2021 Grandby and my roof "tin cans" also - I actually suspected they failed to install VHB when it was built.

With all the changes over the past several years at FWC it is my belief is that the problem originated from improperly trained or supervised employees. Over the years when I have inspected "failures" of specialized bonding agents it has always been traced back to not using the agent properly - most often surface preparation. Some times not using the correct agent for the specific application. And occasionally, not having a proper inspection process installed to prevent failed product from leaving the manufacturer.

So FWC, what will you do to resolve this for your customers?

 

[Wallowa]

I really doubt that there is a "rebuild" solution that is feasible. Not just in terms of numbers and time but honestly how would they be 'repaired'? New top sheets securely glued or screwed to aluminum frame? Like I posted a long time ago my position is that this now my problem to deal with...I do not wish to have my two solar panels, vents and Yakima rails removed and then replaced. Too much to go wrong that could create even a worse problem. Could the existing top sheets be screwed into the frame and not create leaks? You go first and let me know have that worked out...Having noise vs having leaks and I will work on lessening the noise.

FWC is aware of the problem but so far all our discussion about this issue is purely speculative. WAGs. Until the "why" is clearly defined in detail, the "how to fix it" is also pure speculation. In the mean time I will try to stop or lessen the popping/banging/firearm discharge noises on my own. My Hawk, my problem.

I do wonder how and if the securing of the top sheets from now on will change. Hopefully FWC will develop a foolproof attachment method to eliminate the tin canning.

Phil

 

[kmcintyre]

I hear you and maybe your FWC is older but mine is about a year old. If it's a bad design or a failure of a component, etc. it's still under warantee. FWC has been great about fixing and repairing things over the years. That's why we own them and love them. I would expect that if I bought a new vehicle and it had issues, the manufacturer would come up with a solution/repair.

I really doubt that there is a "rebuild" solution that is feasible. Not just in terms of numbers and time but honestly how would they be 'repaired'? New top sheets securely glued or screwed to aluminum frame? Like I posted a long time ago my position is that this now my problem to deal with...I do not wish to have my two solar panels, vents and Yakima rails removed and then replaced. Too much to go wrong that could create even a worse problem. Could the existing top sheets be screwed into the frame and not create leaks? You go first and let me know have that worked out...Having noise vs having leaks and I will work on lessening the noise.

FWC is aware of the problem but so far all our discussion about this issue is purely speculative. WAGs. Until the "why" is clearly defined in detail, the "how to fix it" is also pure speculation. In the mean time I will try to stop or lessen the popping/banging/firearm discharge noises on my own. My Hawk, my problem.

I do wonder how and if the securing of the top sheets from now on will change. Hopefully FWC will develop a foolproof attachment method to eliminate the tin canning.

Phil

 

[Ted]

In my opinion, it is simply the smooth aluminum that is the problem. It was suggested earlier in this thread that FWC take a roof apart to see what is going on. They did just that 10 years ago when I had this issue. The tape had not failed. They had to chisel it off as Stan stated. FWC never had this complaint prior to the smooth aluminum. ATC still uses the corrugated aluminum for their roof and have never had a complaint of the roof popping. The rigidity makes all the difference.

 

[Casa Escarlata Robles Too]

In my opinion, it is simply the smooth aluminum that is the problem. It was suggested earlier in this thread that FWC take a roof apart to see what is going on. They did just that 10 years ago when I had this issue. The tape had not failed. They had to chisel it off as Stan stated. FWC never had this complaint prior to the smooth aluminum. ATC still uses the corrugated aluminum for their roof and have never had a complaint of the roof popping. The rigidity makes all the difference.

Thanks Ted couldn't have said it better.
The corrugated roof material makes all the difference.
Frank
Frank

 

[Jon R]

I checked the roof of my 2021 Grandby and the sheet metal is bonded to the longitudinal frames starting about a foot in from the front and rear edges. I checked it by sticking a small piece of gaffer’s tape to it and pulling up gently at various locations. The VHB tape must be pretty narrow because when I push down on one side of the frame the metal rocks at the frame and the other side rises. If the tape was an inch wide like the frame it wouldn’t do that. Less than a half inch wide is my guess. I’ve used several types of 3M VHB tape so I’m familiar with it.

Now that I’ve studied and played with the top metal a bit and noted how it sags a bit between the frames, I take back my previous statement that the insulation is definitely not bonded to the metal. While I can push the insulation up with gentle force on the head liner, I may have been lifting the metal at the same time.

 

[Wallowa]

OK...but replacing the existing single sheet smooth top sheets with a corrugated one is not feasible...and I do not believe ATC tops are one piece...could be wrong.

If FWC smooth top lacks sufficient rigidity how do you dampen the tin canning?

I am not by any means an engineer but it seems that there are sufficient aluminum struts/frame in the top frame that adequately attaching them to the top sheet would stop the tin canning.

All academic if there is no viable solution at this point....just live with the issue or develop a work around....still working on that

Phil

 

[rubberlegs]

Perhaps adding stiffeners to the inside is more practical. You’d have to remove/replace the insulation and lining though. If there’s a delamination maybe some angles bonded to the top skin and frame could work.

 

[kmcintyre]

Perhaps adding stiffeners to the inside is more practical. You’d have to remove/replace the insulation and lining though. If there’s a delamination maybe some angles bonded to the top skin and frame could work.

The issue is that you can't get the roof line off without taking the roof and vinyl off. The roof fabric is tucked up along the edges (or used to be).

 

[Wallowa]

What do you folks think would this work if placed on top sheet? Only adds 3.6 lbs. Had to laugh from this vendor; 12' only $15.14 but shipping $747, Texas to Oregon....similar on Amazon for less.

Flat ‐ Aluminum ‐ AF.125 X 2.00 X 12'


Enlarge
Flat » Aluminum

• Product Name: AF.125 X 2.00 X 12'
• SKU: 103867
• Weight: 3.60
• Length: 144
• Material: 6061
• Size: 2.00
• Thickness: .125

Description:
6061-T6 ALUMINUM FLAT

 

[Ted]

Wallowa,

I agree it is not feasable to replace the roof. My statement is aimed more at FWC. They prefer to keep the smooth look and single piece despite this known issue and the fact that the seam in the two piece roofs never leaked. I don't have an answer as to what to do as it was never resolved in our camper.
You can get pieces of aluminum like that at places like Lowes and Home Depot, but only in shorter lengths. I think 3' and maybe 6' might be it. Not sure if that would be long enough, but if it is then the cost of shipping is the gas you use to drive there.