Dash Replacement - Why would they use WOOD?

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Dash Replacement - Why would they use WOOD?

July 27, 2016, 06:17:54 pm

I have a 1989 Foretravel Grand Villa U300 Unihome.
I noticed that the front section of the dash would flap in the breeze a bit and in heavy rain, water would bubble up from it.
Upon inspection I realized that the WOOD was totally rotten and I could reach right down into the front of the inside of the fiberglass nose.
This also caused a major issue with the windshield. Because this wood is part of the structure of the front it allowed the entire nose to move with the buffeted wind, I could see the entire structure wiggle a good inch back and forth!!!
This cause the top corners of my windshield to pop out of the gasket! YIKES!!!

So when we pulled the front of the dash out, this is what we found, the wood was rotten, gone, separated into layers.
It was all around screwed.
I couldn't believe that this $300K coach had plywood separating me from the road ahead. Yes, PLYWOOD.

Re: Dash Replacement - Why the hell would they use WOOD?

Reply #1 – July 27, 2016, 06:23:21 pm

Rather that using more PLYWOOD, we decided to get a piece of 92" x 12-1/2" at 1/8" thick ALUMINUM to make a proper firewall and structural support that can be easily water proofed and also keep the giant front fiberglass nose cap rigid.
We used the old wooden dash (what was left of it) to make the template and the defroster holes.

Re: Dash Replacement - Why the hell would they use WOOD?

Reply #2 – July 27, 2016, 06:31:31 pm

Instead of using the WOOD that was GLUED to the fiberglass as a support mount,
we made some brackets out of some 2X2" aluminum angle bracket.
(Check to see if there is a "Metal Supermarket" nearby, they have everything!)
These brackets had to be spread out a bit to match the angle.
Now, here is the thing, you will need to drill through the fiberglass and add bolts through the nose to securely mount these.
You might want to also add epoxy or silicone to them as well.
You can use round head carriage bolts, or screws with washers. We ended up making our own aluminum decorative brackets.
(pictures of those coming soon)

Re: Dash Replacement - Why the hell would they use WOOD?

Reply #3 – July 27, 2016, 06:35:38 pm

Now, this aluminum plate fits in there perfectly. It will be held in by screws and then we will silicone caulk the entire perimeter.
For decorative purposes, we will make another template out of wood that will be covered in vinyl, (we are going to color change it to black, like it should have been in the damned first place!)
It will be screwed down into the aluminum plate to hold it in place.

I will update this thread with photos as we do more additions and answer questions if anyone has any.

Re: Dash Replacement - Why the hell would they use WOOD?

Reply #4 – July 27, 2016, 06:45:41 pm

Post as many photos as you can of your dash area reconstruction. There will be a lot of interest here in your hard work and the results. Problems similar to what you have encountered are (unfortunately) well documented on the Forum. I don't recall anyone else using aluminum in the rebuild, so you may be blazing a fresh trail. Good luck!

Re: Dash Replacement - Why the hell would they use WOOD?

Reply #5 – July 27, 2016, 06:48:19 pm

Foretravel's method of attaching the dash area to the front cap is plenty strong... as long as water isn't intruding. Molding fiberglass to wooden bulkheads is very common in the boat building industry. Leaking windshield gaskets was likely the first cause of your issue. Others have experienced delamination in that area that wasn't caused by water intrusion, but apparently not common. I just had our dash apart, and the substructure of the dash is still firmly attached to the front cap with no rot.

I applaud your decision to use a non-porous alternative for your repair. I had rotten plywood in the basement floor which I replaced with 3/16" aluminum plates. Only issue I can see with your approach is bonding the aluminum to the front cap. I will be following your progress with interest.
Don

Re: Dash Replacement - Why the hell would they use WOOD?

Reply #6 – July 27, 2016, 07:25:21 pm

I found is amazing when you consider that the bottom side of that dash was exposed to the external elements of the world, with wind and rain coming from the bottom.
I suppose if it was coated with fiberglass from the other side it might have helped, but here is why it is a bad idea.

I own, and work on Delorean sports cars.
The outer skins are made of stamped stainless steel that are bolted to a totally fiberglass underbody that sits on a STEEL frame.
To protect the frame, the dipped it in a thick epoxy coating.
Sounds like like it's indestructible right?
Here is where they screwed up.... the steel flexes, the epoxy cracks, water gets inside the cracks and rusts out the metal inside.
When you inspect the car by just looking at it, it looks fine but little do you realize the metal is like shredded wheat inside.
May Delorean frames had to be replaced because of this.

So, I tell that story because when you use a porous organic material like wood and then try to "protect" it,
it is still possible for moisture to creep inside and eat it up.

This is why I am using aluminum. It doesn't rust. It doesn't rot. It will make the front of this thing rigid and solve this issue
and it only cots me $50 in materials.

Re: Dash Replacement - Why the hell would they use WOOD?

Reply #7 – July 27, 2016, 08:31:05 pm

I see... On the Unicoach models at least, the plywood dash structure is inside the body of the coach. There is no easy path for moisture to get to it, except through a leaky windshield. I would have preferred that Foretravel Glass the whole plywood dash structure rather than just the first few inches of the top and bottom where it attaches to the front cap, but on ours at least, no sign of water having been in contact with it. I still wonder how you are going to attach the front cap to the aluminum, but my guess is that you will use mechanical attachment. Perhaps snap fasteners with screws attached to some angle stock riveted to the underside of the dash?
Edit: Never mind, I see now that you answered that above.
Good luck with the project!
Don

Quote from: videobob – July 27, 2016, 07:25:21 pm

I found is amazing when you consider that the bottom side of that dash was exposed to the external elements of the world, with wind and rain coming from the bottom.

Re: Dash Replacement - Why would they use WOOD?

Reply #8 – July 27, 2016, 08:39:59 pm

The water is not from the outside, it's condensate from the interior that runs down the glass and pools up on top of the plywood. Drilling several "weep holes" to allow water to drain down seems to help, along with using Dri-Z-Air.

Re: Dash Replacement - Why would they use WOOD?

Reply #9 – July 27, 2016, 08:48:10 pm

One of the big culprits are the running lights above the windshield---- that is usually where the water intrusion starts. The glues that were used were not waterproof, so delamination followed. I had the problem with my 96' U320. I replaced the damaged dash with marine plywood and used 3M 5200 to seal it to the front cap. Works great.

Re: Dash Replacement - Why would they use WOOD?

Reply #10 – July 27, 2016, 10:56:26 pm

For me, the water came from two places, the center rubber strip between the glass would leak at the top and the bottom and pool there in the center. Not only that, the bottom side of that wood is exposed to the outside via the front grills and the road below.
There is basically nothing between that and the road.
In a heavy rain, water would literally blow up into the cab through the front of the dash!!!

Re: Dash Replacement - Why would they use WOOD?

Reply #11 – July 27, 2016, 10:57:57 pm

"This is why I am using aluminum. It doesn't rust. It doesn't rot."

I can assure you that unprotected or improperly protected aluminum will corrode. We replace aircraft structures routinely due to corrosion. I highly recommend you treat your new pieces with Alodine and a quality epoxy primer. They will then likely outlast most of us.

Re: Dash Replacement - Why would they use WOOD?

Reply #12 – July 27, 2016, 11:00:43 pm

Here are the exterior custom brackets we made to hold on the inside mounting points.
This was slightly more attractive than just using washers but also adds strength.
Remember, the link made between this aluminum dash binds the front of the nose to the inside structure of the coach,
the weight of the windshield and the fiberglass is resting on this.
When you get behind a tractor trailer and begin to draft him, the suction can move the front nose cap by a full inch
back and forth! This will give it rigidity and needs to be sturdy enough that the screws won't pull through the fiberglass.

Re: Dash Replacement - Why would they use WOOD?

Reply #13 – July 27, 2016, 11:03:15 pm

This is the wood cap that will be wrapped in vinyl and then glued/screwed to the aluminum plate.
Because the old plastic defroster bezels are toast and brittle, we decided to get creative.
We made the openings extra wide and will install an expanded metal mesh in-between, while wrapping the vinyl
underneath them for a clean look.
This is the best we can do on short notice.
I have a 5000 mile trip to this weekend!!!

Re: Dash Replacement - Why would they use WOOD?

Reply #14 – July 28, 2016, 01:04:41 am

There is a lot of flex in the unihome structure.

I took these off road in serious off camber areas and used the manual leveling levers to correct the body roll.

I have both broken and twisted windshields out of the gasket.

Was very fun to be able to use a quality Rv in places that no one thought you could get a coach into.

The reenginering you are doing should work out well.

Most would not ever do what I and my customers did with your coach long ago.

Worked ok. A few windshields type stuff.

You are changing the basic design.

Who knows what may show up if pushed?

Cm an pe ray are not around to ask anymore.

Should be an interesting test.

Odds are its a better idea.

Odds are odds.

The coach flexes a lot.

The unicoach flexes hardly at all.

Re: Dash Replacement - Why would they use WOOD?

Reply #15 – July 28, 2016, 03:13:00 am

Thanks for that, I was wondering what I would do with mine, The flex in the front cap has been horrendous, it floats about an inch either way,
But mine is due to the right hand drive conversion, They have cut the dash and swapped it over, So now it floats sideways,
I want to fix it all up before I put my two new windscreens back in, as it does crack the windscreens,
I was going to brace it across under the dash, as the dash is in sections and not connected to any thing,
Then I was going to stiffen up the angles under the dash from the chassis and diagonal brace it,
So it would be rigid, and not flex,

Re: Dash Replacement - Why would they use WOOD?

Reply #16 – July 28, 2016, 06:20:51 am

Quote from: Don & Tys (AKA acousticart) – July 27, 2016, 08:31:05 pm

I see... On the Unicoach models at least, the plywood dash structure is inside the body of the coach. There is no easy path for moisture to get to it, except through a leaky windshield.
.....
Don

I hate to differ with one of our experts but...
Many chilly mornings (obviously not while we are home in Texas) we have awakened to significant condensation on the inside of the windshields. Particularly if we had to use the furnace(s).
We had FOT recover our dash area and they had to completely replace the underlying plywood.
HTH

Re: Dash Replacement - Why would they use WOOD?

Reply #17 – July 28, 2016, 07:07:50 pm

This is the aluminum replacement screwed and caulked into place with the defroster vents glued in from the backside.
This should be wind and water proof.

Re: Dash Replacement - Why would they use WOOD?

Reply #18 – July 28, 2016, 07:26:48 pm

Today was a scary day.
I had some glass guys come out to "adjust" the windshield.
They took it completely out and put it back in.
I learned a lot about what a bad design our windshields are and what YOU should do if you are ever faced with this issue yourself in the future and what you should prepare for...

Here is one of the main issues, the top of the nose cap flexes tremendously when the couch is twisted when it "levels".
If you are going to work on the windshield make sure it is sitting level with the air-bags or level jacks down.
You don't want any un-even pressure, it can push the glass out by as much as an inch in any direction once you remove
the lock -strip from the rubber gasket.

Here is where Foretravel screwed up... between the two windshields is basically NOTHING, there is a 1/8" gap that is generally filled with caulk and they glue a rubber strip over it.
What SHOULD be there would be a large "H" gasket, you will want to get some 1/4" double sided H gasket, the larger the better,
2" is perfect.
In my opinion, what would be a perfect solution would be to mount an angle bracket to the top and bottom of the center with a long double threaded rod that can be tightened in the center to pinch the top cap down and pull it together to keep a tight seal.

Anyway, the way they put the window in is that they take the gasket (preferably a new one) is that they glue it into place with urethane and want to let it sit overnight to cure before they put the glass back in.
When they do put the glass back in, they will then use the caulk to fill in the gaps and seal it into place.
Because of this method, you will want to pay attention to certain corners in the window frames that will need to be filled with a
flexible silicone filler. I say FLEXIBLE because it will move while the coach twists in travel.
You will need to periodically remove it and refill it, at least yearly.

Bottom line is that the slant nose design was dropped because of this issue.
It was discovered that the only way to keep this from happening was to have one large windshield that is GLUED in totally vertically and make the front nose cap as small as possible.
So unfortunately this is going to be a problem as long as you continue to drive the coach.
If it is a stationary full time live in and sitting level it will be fine, but every time you pull in and out of a sloped driveway at an angle or level the coach when it is sitting on a slope the nose cap will continue to flex and flex the windshield.

If you plan to own one of these for a long time, you might be smart to go ahead and buy a pair of windshield glass and put them in storage.... just saying.

Re: Dash Replacement - Why would they use WOOD?

Reply #19 – July 28, 2016, 07:46:20 pm

Then I defer to your experience! It depends then upon where and when the coach is... I have only seen condensation once on the inside of our windshield since we have had it, and I don't plan to ever be anyplace that cold again! Also, I guess we are lucky in that respect, since our coach must have been used in a likewise fashion, having no sign of water intrusion in the plywood. My point however, was that the underside of the plywood is not exposed to the elements on the Unicoach. I can confidently state that definitely, having just had the dash completely apart.

Don

Quote from: TheBrays – July 28, 2016, 06:20:51 am

I hate to differ with one of our experts but...
Many chilly mornings (obviously not while we are home in Texas) we have awakened to significant condensation on the inside of the windshields. Particularly if we had to use the furnace(s).
We had FOT recover our dash area and they had to completely replace the underlying plywood.
HTH

Re: Dash Replacement - Why would they use WOOD?

Reply #20 – July 28, 2016, 08:17:42 pm

Was told by someone at the factory that every windshield job gets a new 1-1/2" gasket. Our water problem is from the inside, at times we run the cooling fans and the ac unit with the heat strip on, that's how Oregon winters are.

Re: Dash Replacement - Why would they use WOOD?

Reply #21 – July 28, 2016, 08:45:42 pm

Indeed, rotting of the dash wood can happen, but is pretty rare.

Two primary causes:
Condensation on the inside of the windshield is the main one. When condition produce this much moisture on the inside, open a vent/window to let in some outside air. Exhaust fan on when showering or cooking. Worse case, use a towel to dry the windshield.

Leaking (for a long time) windshield gasket is the other one.

Very rare for enough water to come from the front to rot the wood-- at least I have never seen it in the many, many coach inspections I have done.

Said another way, if there is rot, my observation is that it is always worse on the top (see two causes above) than on the bottom.

Re: Dash Replacement - Why would they use WOOD?

Reply #22 – July 28, 2016, 08:47:09 pm

Looking at the outside of the front as shown in pictures that body work is not in the greatest of conditions, looks like it is in lousy weather all the while and not looked after with polishes and possible needed as needed at times. Yes there is movement in that GV style windscreen but rotting is something that we have to be very carefull of keeping things clean and dry, as in many construction issues. My feeling is that coach has sat for ages without anyone checking on what was going on ie condensation and leaks etc. If all issues are not looked after they will bite hard sooner or later, be it body or mechanical.
I doubt(in my opinion) that this issue changed the design of the coach's as I am sure it was more a point of the "Bus" style front end coming into fashion as the slanted front does date it, but having said that a lot of us love the GV styling and quality.
FWIW
JohnH

Re: Dash Replacement - Why would they use WOOD?

Reply #23 – July 28, 2016, 09:04:29 pm

On our '89 GV the windshield gasket, on the passenger side--bottom center--where the ends met--had separated almost an inch due to shrinkage/age. When it rained water would pour in!! So I filled the gap with a liquid rubber and the water intrusion stopped. I keep a close eye on the "joint" and do renew the sealer every couple years.
Without that maintenance I think folks here would be reading about my rotted/damaged dash wood.

Re: Dash Replacement - Why would they use WOOD?

Reply #24 – July 28, 2016, 09:15:43 pm

All of us that own GV's need to be really careful about jacking and de-jacking, do both fronts together and front and rear sides together, don't twist or you will loose your glass.

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