Putting two solar panels on my RV, but it has a slight crown in the roof

[rockwind1]

In case you’re wondering, the rest of the roof is full with other solar panels that I was able to mount parallel to the crown so I just used regular Z brackets. Obviously the problem that I see is that the four mounting holes on each side of the long side of the solar panel are all going to be at different heights, has anybody dealt with this problem? I was gonna wire two of these panels together and run it into that charge controller.

 

[Rednecktek]

I've run into that before. I was using T-channel track to hold bolts upright through the bottom of the Z-brackets. I just had to use slightly longer bolts on one side and put a few washers under the Z-bracket as spacers to get it straight. Pretty easy solve.

 

[0truck0]

aluminum L-angle.

Get aluminum L-angle iron that is tall so you can make up for the slope. Get one piece that is not tall for the crown, and one that is tall for the edge. You drill a hole as needed on the angle iron to achieve height and drill into the aluminum solar panel frame without hitting the glass and that will be good. You might put rubber washers between the two so that helps with the pieces not fitting together flushly due to the roof angle.

different roof, but same concept
These are not bolts, just self tappers, self drillers, but I drill holes in angle iron, then let the screw drill n tap into the panel. Much easier than dealing with nuts n bolts and over 4-5 vehicles like this have never come loose, and yes, that is plenty contact to hold a panel in all conditions.

 

[rockwind1]

aluminum L-angle.

Get aluminum L-angle iron that is tall so you can make up for the slope. Get one piece that is not tall for the crown, and one that is tall for the edge. You drill a hole as needed on the angle iron to achieve height and drill into the aluminum solar panel frame without hitting the glass and that will be good. You might put rubber washers between the two so that helps with the pieces not fitting together flushly due to the roof angle.

View attachment 285547different roof, but same concept
These are not bolts, just self tappers, self drillers, but I drill holes in angle iron, then let the screw drill n tap into the panel. Much easier than dealing with nuts n bolts and over 4-5 vehicles like this have never come loose, and yes, that is plenty contact to hold a panel in all conditions.

not a bad thought but I think i am going a different route, i wanted to use the stock holes on the bottom, i don't trust self tappers when panels are on a rv roof.

 

[grizzzman]

not a bad thought but I think i am going a different route, i wanted to use the stock holes on the bottom, i don't trust self tappers when panels are on a rv roof.

Use two pieces of angle on every connection using the original panel holes. In this way if for any reason the panel needs to be removed it's no biggie.

 

[HRTKD]

Those panels are big enough that they should be supported with six brackets.

An alternative configuration is to turn the panels 90°, with one on each side of the trailer, closer to the edge of the roof. You may not have room to do this if you have a narrow camper. Mine is 102" wide with a 6" crown, so I (mostly) had room. The downside of this configuration is that the panels are now pointing in different directions and they should be wired in parallel, not series. As long as you have a 12 or 24 volt system, that's OK. It would not work for a 48 volt system because the Voc of the panels is well below 60 volts.

All my attachment points at the solar panel use stainless steel bolts and lock nuts. I don't trust screws.

 

[Aussieguy]

I used 3 x 370w panels similar size to yours

PUT them lengthwise along the roof side by side
trailer is 8 foot wide... gives me a bit of a walkway between panels at the roof crown

used 4 brackets down each side of the panel
followed the ROOF curve/crown so panels are at small angle (not dead flat) water and dirt do not accumilate....
Have not needed to wash them 12months .... as the rain removes all the crud

 

[0truck0]

The only time I have ever seen self tappers (the ones that drill itself then screw into that drilled hole, aka tech screws) is if they break. We use these at work and are liable for millions if they fail and they never have. Breakage is usually over-tighten to the point it breaks and I cant think of one breaking while in service. They NEVER come unscrewed never ever, at work or on the roof holding panels, never and never been an issue. I worry more about nut and bolt unscrewing than a tapper. Tapper is the safest way to go and also the easiest, and dont let people panic you into thinking panel mounts need to be built like fort knox, they do no, the most basic metal you get will likely be overkill. I have examples of what looks insanely scary too little of a mount and yet drive 10,000 miles in horrible winds and off road and never have to worry. You are going to over-build it, that is an almost certain, and now you are going to spend over budget for little to no, or even worse, safety

 

[HRTKD]

They NEVER come unscrewed never ever

My project this weekend on my RV will be replacing the self tapping screws. A number of them have come loose. One was flat out missing. This is on the aluminum skirt of my RV. I suspect that the vibration from the wind going down the road shook them loose. They'll be replaced with stainless steel bolts, rubber washers, stainless steel washers and stainless steel lock nuts.

 

[dktool]

I did this on mine;

 

[0truck0]

My project this weekend on my RV will be replacing the self tapping screws. A number of them have come loose. One was flat out missing. This is on the aluminum skirt of my RV. I suspect that the vibration from the wind going down the road shook them loose. They'll be replaced with stainless steel bolts, rubber washers, stainless steel washers and stainless steel lock nuts.

A bolt on my rocking chair broke, so what's your point. Let's keep discussion to solar panels, that we are talking about, and not your skirts. Yea, things break. I think you are looking for the skirt forum, not solar panels topics. All you silly people trying to scare people into hiding under their beds or something. Show me a broken tapper on your solar panel install please. I can show you a dozen that have not broken and are still as tight as the day installed and have driven 100,000 miles with little bitty pieces of VHB tape holding them to the roof. Please.
The only broken tapper I have ever seen, regarding solar installs, not skirts, is one that was over-torqued with an impact driver.

 

[HRTKD]

Let's keep discussion to solar panels, that we are talking about, and not your skirts.

Putting on my moderator hat...

The topic of fasteners was started by you in post #3. @rockwind1 said in post #4 that he didn't like self tappers for panels on a roof. In post #5 I added that I also don't trust screws. The topic of fasteners is relevant to the topic of this thread and will continue whether you like it or not. If you choose to argue with me on this point there will be consequences.

Moderator had off...

Fasteners for solar panels on the roof of an RV are, in my opinion, a safety item. Insufficiently securing the panels to the roof of an RV can result in a panel flying off while on the road, which puts other drivers in danger.

 

[0truck0]

Putting on my moderator hat...

The topic of fasteners was started by you in post #3. @rockwind1 said in post #4 that he didn't like self tappers for panels on a roof. In post #5 I added that I also don't trust screws. The topic of fasteners is relevant to the topic of this thread and will continue whether you like it or not. If you choose to argue with me on this point there will be consequences.

Moderator had off...

Fasteners for solar panels on the roof of an RV are, in my opinion, a safety item. Insufficiently securing the panels to the roof of an RV can result in a panel flying off while on the road, which puts other drivers in danger.

thanks, you can take the hat off now. I disagree with you on all points and feel you have not used tappers or always somehow use them incorrectly. Talking about skirts breaking has nothing to do with the topic and really does not translate over to heavy gauge metal and professionally installed fasteners. I advise you to personally have someone else do all the work for you, but for others I feel they can decide for themselves if proven and safe fasteners are something they can tackle. Feel free to have your own opinion but if you want to disagree please come with better evidence than skirts. Skirts I assume are some flimsy junk you put on incorrectly that flapped constantly 24/7 and tore as would be expected. If you have examples of tapers breaking off when used on real metal, the kind being discussed then we would like to see where the fail was.

 

[Backyard]

I don't know why something like this wouldn't work

 

[HRTKD]

I don't know why something like this wouldn't work

View attachment 286816

That's fine. The only thing I would change is to use a lock nut. For fastening solar panels I use lock nuts not lock washers.

In that picture, frame #1, it looks like the lock washer is on the head end of the bolt. The lock washer should be on the nut end. Frame #2 looks like the lock washer is on the nut end. Kind of odd that the two frames don't appear to agree.

 

[Backyard]

That's fine. The only thing I would change is to use a lock nut. For fastening solar panels I use lock nuts not lock washers.

In that picture, frame #1, it looks like the lock washer is on the head end of the bolt. The lock washer should be on the nut end. Frame #2 looks like the lock washer is on the nut end. Kind of odd that the two frames don't appear to agree.

I was referring more to the bracket. But good points none the less

 

[Supervstech]

thanks, you can take the hat off now. I disagree with you on all points and feel you have not used tappers or always somehow use them incorrectly. Talking about skirts breaking has nothing to do with the topic and really does not translate over to heavy gauge metal and professionally installed fasteners. I advise you to personally have someone else do all the work for you, but for others I feel they can decide for themselves if proven and safe fasteners are something they can tackle. Feel free to have your own opinion but if you want to disagree please come with better evidence than skirts. Skirts I assume are some flimsy junk you put on incorrectly that flapped constantly 24/7 and tore as would be expected. If you have examples of tapers breaking off when used on real metal, the kind being discussed then we would like to see where the fail was.

I am not following your logic.

You state you NEVER have ANY tapper screws come out on your projects, i believeyou state MILLIONS in liabilities if they were to fail.

Odd...

Self tappers or self drilling, i assume you are talking about, since we are discussing metals...
Shall not be used anyplace BOTH sides are accessible, as a nut and bolt is superior.

In other words, ya should only use bit tip, or self tapping screws in blind locations.

Just going by the use cases listed for the screws.

Now, anybody can use whatever they feel like, and likely consequences be damned...

But if, someone doesnt feel tappers should ve used... why argue the point?

Why argue what someone ELSE should or should not use?

 

[Backyard]

Let's get our terminology correct guys

 

[Aussieguy]

and use lots of good self leveling sealant

I attached my Z barckets to panels in the garage where is nice and cool
put them up on the roof and then in position
pre-drilled a small pilot hole and then LIFTED the panel up a bit ............. using a block of wood to hold it UP as I put gobs and gobs of the sealant under the bracket then put the panel back down.

that sealant got all over the tools , but sure did a great job of making sure no water is getting in my roof
USED hand tools only.................. so I was sure not to over tighten and strip out the holes
( very easy to strip a hole if you use power tools)

once all screws were in place more sealant over the top of the hex head
and some well place dollops also keeps the wires neat and tidy ... glued down onto the roof


PS don't install panels in Florida on a good sunny day.... Damnnn they get scorching hot real fast!

 

[littleharbor2]

and use lots of good self leveling sealant

I attached my Z barckets to panels in the garage where is nice and cool
put them up on the roof and then in position
pre-drilled a small pilot hole and then LIFTED the panel up a bit ............. using a block of wood to hold it UP as I put gobs and gobs of the sealant under the bracket then put the panel back down.

I would definitely use something like or equivalent to 3M 5200 urethane adhesive sealant. That stuff is so strong you can take the screws out and it won't come off with just the sealant, alone holding it. It's amazingly strong.

 

[0truck0]

"self-tapper" is a catch all because they all self tap, whether they self drill or not has no significance at all other than you know the drill hole is the right size and that the person installing does not have to use a separate drill bit to install, which means your drill bit never goes dull n needs replacing. I have even used tappers to drill a hole because they are super cheap compared to drill bits and you dont have to climb back down the ladder to get a drill bit either.
Industry guys will call everything self-tappers because who cares... You can use tappers whenever you want, not just for blind work. They are great because they work and they work good and are quick and cheap. Failure is common with new guys who do not know when to release the trigger on the impact driver, they snap the head off. When the bit stops turning you stop driving!
You also have to have the right self-driller if the metal is thicker than the drill bit portion of the screw because the hole needs to be drilled before the threads come into contact and start aggressively pulling the screw in. Too short a drill section and you will break every screw every time.

They guy with the skirt wanted to argue that because his project went wrong that it must be the fault of the fasteners, not his own fault. That was the bad logic. You dont have to use nuts/bolts because a flimsy skirt ripped apart. We are talking about metal frames, not sheet metal, so forget everything about skirts.

The only bad part is that if you do snap one then you have to start a new hole because, unlike a bolt, it will not fall out when broken, and it is not worth it to try to drill the hardened fastener out. You will be able to hear the impact driver's sound change when it is time to stop. Practice on metal if you are new before doing your project. I have driven thousands of these so is easy by now...

If you have access behind then using nut/bolts is perfectly fine. I advise using two nuts so you can lock them from coming loose.

The stresses on solar panels on a roof are next to nothing.

 

[Supervstech]

"self-tapper" is a catch all because they all self tap, whether they self drill or not has no significance at all other than you know the drill hole is the right size and that the person installing does not have to use a separate drill bit to install, which means your drill bit never goes dull n needs replacing. I have even used tappers to drill a hole because they are super cheap compared to drill bits and you dont have to climb back down the ladder to get a drill bit either.
Industry guys will call everything self-tappers because who cares... You can use tappers whenever you want, not just for blind work. They are great because they work and they work good and are quick and cheap. Failure is common with new guys who do not know when to release the trigger on the impact driver, they snap the head off. When the bit stops turning you stop driving!
You also have to have the right self-driller if the metal is thicker than the drill bit portion of the screw because the hole needs to be drilled before the threads come into contact and start aggressively pulling the screw in. Too short a drill section and you will break every screw every time.

They guy with the skirt wanted to argue that because his project went wrong that it must be the fault of the fasteners, not his own fault. That was the bad logic. You dont have to use nuts/bolts because a flimsy skirt ripped apart. We are talking about metal frames, not sheet metal, so forget everything about skirts.

The only bad part is that if you do snap one then you have to start a new hole because, unlike a bolt, it will not fall out when broken, and it is not worth it to try to drill the hardened fastener out. You will be able to hear the impact driver's sound change when it is time to stop. Practice on metal if you are new before doing your project. I have driven thousands of these so is easy by now...

If you have access behind then using nut/bolts is perfectly fine. I advise using two nuts so you can lock them from coming loose.

The stresses on solar panels on a roof are next to nothing.

Translation:
Screws work with practice and in his opinion work fine for panels.
If a nut and bolt are possible, double up the nuts for best security.

 

[Supervstech]

The stresses on solar panels on a roof are next to nothing.

The stress on ANYTHING IN A MOBILE ENVIRONMENT is constantly changing.

 

[Dagoth Ur Does Solar]

I did this on mine;

How do you guys resist not covering every inch of the roof in panels?

 

[Rednecktek]

How do you guys resist not covering every inch of the roof in panels?

Stupid things like vents and air conditioners get in the way, plus panel sizes never exactly match up to roof sizes. Otherwise we pretty much do.