Roller Bed Cover Might Be Leaving

Hunter

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As a retired general contractor, builder, and professional roofer, the more I think about this roll top cover idea for the CT bed, the more I think it's wrong. It breaks the first law of roofing:

1 - Overlap things mechanically.

Calking and fancy seals always fail and leak. Put upper layers over top of lower layers, and never the reverse.

How do you build this into the roll top cover for a truck bed? You don't. It's impossible. Therefore, any design of a roll top cover will eventually leak one way or another. The reason is because it breaks the first law of roofing. It's mechanical overlapped wrong.

Now add to this: wind blown rain, and you have a soggy, double leaking problem.

If there is wind, (like driving in rain at highway speeds), then the overlap needs to be more.

I fix roofs on a regular basis where the roofer broke the first law. To makeup for getting the layer order wrong, where they had put lower layers over top of upper layers, they then apply sealant of one sort or another. It works for awhile, then it fails. The roof has to be torn apart, and the positional order of the roofing materials corrected so that upper layers are applied over top of lower layers. It's usually a very expensive repair.

I don't want a leaky back-end on the CT! This really needs to be fixed, and in a really good way.

I have a nice aluminum work shell for my truck. For the most part it doesn't leak. In other words, in the roof and doors, for the most part, they built it so that it mechanically overlaps lower parts with upper parts to keep the wet out.

But still, it leaks at the side seals. They should have overlapped the bed with the shell a little bit.

Where they broke the first rule of roofing, and tried instead to rely on foam sealant, it leaks.

The only way is to design the CT back end, it so that it obeys the first law of roofing is to overlap things correctly.

If you can't do that, then leave it open.

 
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rr6013

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Optimistic is society manages to stumble along for at least another 50-100 years.

Pessimistic… I’m converting to solar/ off grid capable, live in a bunker-like concrete dome, and drive a truck I can self fuel and drive anywhere.

Either plan, I’ll still want our Kubota capable of diggin in the dirt.



1640547620674.jpeg


1640547673877.jpeg
Looks like the Tesuque NM place we had. 14” thick adobe walls would cycle ~8hrs holding temps comfortable @7000 feet elev.

A concrete dome; ceiling fan & a pellet stove would do .v. central air which ate propane $108/mo. in winter. Love the Kubota plan to dig your way out of jeopardy. Pack rats killed our back-to-Nature greenhouse. Man we dumped the bucks on nice plants for those rats!

D18B885F-87D1-4086-9015-1666E8830568.jpeg
 

HaulingAss

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As a retired general contractor, builder, and professional roofer, the more I think about this roll top cover idea for the CT bed, the more I think it's wrong. It breaks the first law of roofing:

1 - Overlap things mechanically.

Calking and fancy seals always fail and leak. Put upper layers over top of lower layers, and never the reverse.

How do you build this into the roll top cover for a truck bed? You don't. It's impossible. Therefore, any design of a roll top cover will eventually leak one way or another. The reason is because it breaks the first law of roofing. It's mechanical overlapped wrong.

Now add to this: wind blown rain, and you have a soggy, double leaking problem.

If there is wind, (like driving in rain at highway speeds), then the overlap needs to be more.

I fix roofs on a regular basis where the roofer broke the first law. To makeup for getting the layer order wrong, where they had put lower layers over top of upper layers, they then apply sealant of one sort or another. It works for awhile, then it fails. The roof has to be torn apart, and the positional order of the roofing materials corrected so that upper layers are applied over top of lower layers. It's usually a very expensive repair.

I don't want a leaky back-end on the CT! This really needs to be fixed, and in a really good way.

I have a nice aluminum work shell for my truck. For the most part it doesn't leak. In other words, in the roof and doors, for the most part, they built it so that it mechanically overlaps lower parts with upper parts to keep the wet out.

But still, it leaks at the side seals. They should have overlapped the bed with the shell a little bit.

Where they broke the first rule of roofing, and tried instead to rely on foam sealant, it leaks.

The only way is to design the CT back end, it so that it obeys the first law of roofing is to overlap things correctly.

If you can't do that, then leave it open.
If anyone can build a roll-top tonneau cover that doesn't leak, it would be Tesla. That said, all existing roll-top tonneau covers can leak a little seep under adverse conditions. In fact, most tonneau covers, roll-top or not, leak under adverse conditions. It might take a fire hose directed at just the right angle, but they will all leak. That is no reason not to have a cover. I live in a very wet, rainy climate and my tonneau cover is a lifesaver. Any leaking it does is minimal enough and seldom enough to be a non-issue. A real issue is the cab on the my 2010 F-150 which has leaked a small amount of water since it was brand new and not one dealer out of three has ever been able to find and seal the leak.

As to over-lapping edges correctly, that's true. But I'm not sure why you think the Tesla tonneau will not have proper overlaps. You may be a retired general contractor, builder, and professional roofer, but I bet you have never engineered a roll-top tonneau cover! Because you can't tell how much overlap was used by looking at photos. The overlap is often placed out of sight and the water is designed to run in channels just under the top surface where it can exit through front/rear drains that exit under the vehicle.

For example, look at the rain seals where your side windows enter the metal part of the door. There is a rain seal there but it doesn't overlap and water can leak right past it into the inside of the door. The point is, the water is managed and drained out the rear of the door without getting your stuff wet.
 

Ogre

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Most truck beds are designed to drain out the back.

I’m not sure what the big deal here is in general, it’s a truck bed. Truck beds are outside storage. You expect your load will be exposed to some weather. That’s the nature of truck beds. Your load will be 99.9% drier than if it was uncovered.
 

Friday

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The worst water damage I've seen to pickup truck beds was water getting under the plastic bed liner and staying wet for a long time due to lack of circulation to dry out. I've seen this even with a truck with a cap on it where sideways rainstorm blew water through side seals. Rust, rot, stink, carnage, and not uncommon.

All the modern pickups seem to have drain holes in the bed for water. Why wouldn't the CT?

Also, if moisture fear is an issue, there are leak detection systems that are readily available. I see wireless one's all over some of the manufacturing sites I have visited. Sensors would be easy to add in an electric truck, right?
 

jhogan2424

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As a retired general contractor, builder, and professional roofer, the more I think about this roll top cover idea for the CT bed, the more I think it's wrong. It breaks the first law of roofing:

1 - Overlap things mechanically.

Calking and fancy seals always fail and leak. Put upper layers over top of lower layers, and never the reverse.

How do you build this into the roll top cover for a truck bed? You don't. It's impossible. Therefore, any design of a roll top cover will eventually leak one way or another. The reason is because it breaks the first law of roofing. It's mechanical overlapped wrong.

Now add to this: wind blown rain, and you have a soggy, double leaking problem.

If there is wind, (like driving in rain at highway speeds), then the overlap needs to be more.

I fix roofs on a regular basis where the roofer broke the first law. To makeup for getting the layer order wrong, where they had put lower layers over top of upper layers, they then apply sealant of one sort or another. It works for awhile, then it fails. The roof has to be torn apart, and the positional order of the roofing materials corrected so that upper layers are applied over top of lower layers. It's usually a very expensive repair.

I don't want a leaky back-end on the CT! This really needs to be fixed, and in a really good way.

I have a nice aluminum work shell for my truck. For the most part it doesn't leak. In other words, in the roof and doors, for the most part, they built it so that it mechanically overlaps lower parts with upper parts to keep the wet out.

But still, it leaks at the side seals. They should have overlapped the bed with the shell a little bit.

Where they broke the first rule of roofing, and tried instead to rely on foam sealant, it leaks.

The only way is to design the CT back end, it so that it obeys the first law of roofing is to overlap things correctly.

If you can't do that, then leave it open.
I can’t believe this is still being debated. We have rain coming soon. I may just pull my truck out of the building so it can get rained on and take a picture of the dry bed and all the debris that is not clogging it up. There is waaaaaay too much thought going into this. The bed covers work. Why aren’t we discussing the tire compound or seat fabrics? Anything but this.
 

Luke42

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If the tonneau cover leaks, the vault becomes a water holding tank. Added feature for those wanting integrated holding tanks.
My pickup truck bed has drains. They're artfully hidden in the forward corners of the bed. The other drain point is through the gap in the tailgate.

 

 

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