Solar Panel Mounts

[SoonDockin]

I have an Arctic Fox 1140 with the round roof. I have some 200w panels that are 5ft by 26". I can use the simple z mounts and have the same issue if I ever want to remove them. So I have been considering using 2 4040 aluminum extruded rails mounted with L brackets so its somewhat level. I end up with only 8 8mm screws holding the entire assembly down. Will this be enough?

[Camper_Jeff___K]

People rave about this super adhesive tape. You have to remember this tape is purpose built for aircraft, designed to be applied to a well understood engineered surface. An RV roof is not a comparably well engineered surface. Sure the tape may stick to the visible surface, but what of the materials beneath that? The adhesive on the tape probably far out classes the adhesive on the roof if any. Your panels may cause the roof material to separate and start bouncing around and before long, the panels are hanging over the side of the RV being held as long as the MP4 connectors last. There is no replacement for brackets, SIKAFLEX or 5200 adhesive caulk and some stainless screws and brackets. I used L brackets with #12 ss screws that I mounted to the roof making sure to position them where I could feel a roof joist I could screw into. The L brackets have three SS screws going into the solar panel frames for a very good solid connection all set into very durable adhesive caulk as mentioned. The solar system with 4 panels is working beyond expectations. I have not needed to plug into shore power since installation. On another note some people miss about the DC to DC charger, You really need to get one if you are going to run lithium batteries. Lithium batteries will accept so much charge current, they will place enough demand on your alternator that it will start smoking and burn out. Also, if you have a 12 volt charge wire, disconnect from the RV because it will not be doing you any good. It will probably operate at a lower voltage than the DC to DC charger and back feed to your vehicle throwing off your vehicle computer engine management control readings. What you can do with that 12 volt charge wire is use it as the engine running trigger wire for the DC to DC controller, turning it on and off when the vehicle is running or not. Confirm the 12 volt charge wire is key controlled. There you have it, an honest 2 cents worth with inflation accounted for. If you're interested, here's the video I did showing off my solar setup, though it's not intended as a technical how to installation video, but just a show and tell. Take care...
Solar System Show and Tell

[deltabravo]

jdcellarmod wrote:
On my 2020 AF 865 I used the AM Solar L foot rocker foot mounts.

AM Solar has the best mounting system, I have ever seen for RV solar panels.

I used their panels and mounts on my AF811 as shown in this video

If I ever do another RV Solar project, I will not hesitate to user their mounts and panels again.

[memilanuk]

For me, it was a matter of having the rubber flange on the wrong side of the bracket (strut). I thought I could have it on the top side, and still be able to draw it down tight. When I did, it pulled the whole thing right through the hole.

Discarded that well nut, grabbed a new one, put it so that the flange was directly on top of the roof, with the strut channel on top of that, added washers, inserted the bolt, and snugged it down. Adding to the level of 'fun' was that I'd already put a bunch of Dicor around the flange / under the strut, so it was pretty messy the second time around. Took some doin' to get everything cleaned up.

That said, there's a point where the bolt head draws down flush, and then where it begins to snug up... which is usually the sign to *STOP TIGHTENING*. There really isn't a hard 'stop' feeling like with a metal-on-metal fastener... so I guess if you just kept turning and turning waiting for it to get tight and stop, yeah, you'd pull the threaded insert right out.

[Geewizard]

memilanuk wrote:

Geewizard wrote:
I tried well nuts for my solar panel mount (using Z mounts). They pulled right out.

Well, 17 years later it's obviously too late to argue about how exactly you did the install... but in my limited experience (putting several of them in last fall/winter), on the first attempt (or two) they *did* pull 'right out'. Turned out it was a mistake on *my* part, and when I went back and did it correctly, they held very solidly.


The metal version aka 'riv-nuts' should work at least as well, with the slight difference of not being inherently water-tight. Since most people are going to cover everything in sight with some kind of sealant, it's debatable whether that's worth it or whether it's better to go with some thing that is mechanically stronger like you did.

Either way works.

What was your mistake in putting in the well nuts and how did you do it correctly? I distinctly remember drilling the proper size hole, inserting the well nut, and tightening the screw. In my case, the brass insert in the rubber pulled out quite easily.

[jdcellarmod]

On my 2020 AF 865 I used the AM Solar L foot rocker foot mounts. I have 2 Zamp 170 watt panels at the rear and 1 70 watt panel in front of the refrigerator vent. The mounts make it easy to remove panels if needed. Their mounts have VHB tape on them. I used the tape along with #8 screws with Dicor all over the base of the mount after they were attached. Take a magnet and run it over the area where you want to place the panel mounts. Northwood places sheet metal in certain places for roof mounted items. I got a roof schematic from Northwood and it showed where all the sheet metal was. 9000 miles later the panels are still in place.

Jeff D

[memilanuk]

Geewizard wrote:
I tried well nuts for my solar panel mount (using Z mounts). They pulled right out.

Well, 17 years later it's obviously too late to argue about how exactly you did the install... but in my limited experience (putting several of them in last fall/winter), on the first attempt (or two) they *did* pull 'right out'. Turned out it was a mistake on *my* part, and when I went back and did it correctly, they held very solidly.


The metal version aka 'riv-nuts' should work at least as well, with the slight difference of not being inherently water-tight. Since most people are going to cover everything in sight with some kind of sealant, it's debatable whether that's worth it or whether it's better to go with some thing that is mechanically stronger like you did.

Either way works.

[3_tons]

deltabravo wrote:

HMS Beagle wrote:
Just VHB tape, on a solid roof, will be stronger than a few #8 screws.

VHB tape attached to rubber roof membrane, with the rubber roof membrane being glued to the underlayment of the roof is a horrible idea.

On any rubber roof RV, the panels need screwed down to the wood under the rubber roof.

Considering the relatively long life of PV panels, I can imagine the ‘lazy installers’ ezy-tape at some point failing (say overtime do to environmental reasons), and the panel projecting through some other distracted driver’s windshield…I’ve even seen Gorilla tape’s uber strong adhesive fail in such conditions…Some poor soul winning the Darwin Award seems fool’s game to me…

3 tons

[Geewizard]

memilanuk wrote:

SoonDockin wrote:
With the thin luan on the top of my RV it seems picking the best screw can be challenging.

Look up 'well nuts'. There is a rubber sleeve with a flange on it, and a metal (brass) insert. You drill a hole big enough for the sleeve to slip into, so it stops on the flange. Then when you screw the bolt in, the threaded insert pulls it towards the head, mushrooming the rubber body and sandwiching the thin wall material (luan, in your case) between the flange and the mushroom. Think of it like a rubber rivet.

Other uses include attaching glass windshields to motorcycles, or providing attachment points on the sides of water craft. They provide a fairly water-resistant connection to begin with, and when utilized underneath a mounting bracket or rail and then covered with additional sealant like Dicor or Sikaflex you shouldn't have any issues with UV degradation either.

I'd double check with the manufacturer (Arctic Fox) about the actual construction of the roof. Adventurer has their 'TCC' i.e. 'true composite core/construction' equivalent, but even that has aluminum frame members, and weirdly enough, three additional random wood cross members. That's in addition to the cheap/light white pine stuff they put around the roof openings for screw holding. I'd be shocked if AF doesn't have *some* kind of structural cross members in the roof.

I tried well nuts for my solar panel mount (using Z mounts). They pulled right out. I wouldn't trust them at all.

I used aluminum rivet nuts placed through the rubber roof/luan and into aluminum roof crossbeams. They have held up since 2005 without fail. A healthy coating of sealant was used.....of course.

Marson Ribbed Rivet NUT KIT

[SoonDockin]

memilanuk wrote:

I'd double check with the manufacturer (Arctic Fox) about the actual construction of the roof. Adventurer has their 'TCC' i.e. 'true composite core/construction' equivalent, but even that has aluminum frame members, and weirdly enough, three additional random wood cross members. That's in addition to the cheap/light white pine stuff they put around the roof openings for screw holding. I'd be shocked if AF doesn't have *some* kind of structural cross members in the roof.

I watched a factory tour done in 2019 by Taylor Dazeman. They show the roof is 100% structual foam with luan laminated on the surfaces. I have replaced two fans and pulled the antenna. Those area are just 4-6" of foam sandwiched with luan.

I might still send them an email as I plan to mount several more solar panels after my next trip.

[memilanuk]

SoonDockin wrote:
With the thin luan on the top of my RV it seems picking the best screw can be challenging.

Look up 'well nuts'. There is a rubber sleeve with a flange on it, and a metal (brass) insert. You drill a hole big enough for the sleeve to slip into, so it stops on the flange. Then when you screw the bolt in, the threaded insert pulls it towards the head, mushrooming the rubber body and sandwiching the thin wall material (luan, in your case) between the flange and the mushroom. Think of it like a rubber rivet.

Other uses include attaching glass windshields to motorcycles, or providing attachment points on the sides of water craft. They provide a fairly water-resistant connection to begin with, and when utilized underneath a mounting bracket or rail and then covered with additional sealant like Dicor or Sikaflex you shouldn't have any issues with UV degradation either.

I'd double check with the manufacturer (Arctic Fox) about the actual construction of the roof. Adventurer has their 'TCC' i.e. 'true composite core/construction' equivalent, but even that has aluminum frame members, and weirdly enough, three additional random wood cross members. That's in addition to the cheap/light white pine stuff they put around the roof openings for screw holding. I'd be shocked if AF doesn't have *some* kind of structural cross members in the roof.

[SoonDockin]

With the thin luan on the top of my RV it seems picking the best screw can be challenging. Self tapping screws seem bad as they remove material that can be compressed to hold the threads a bit more. I have considered using epoxy in the screw hole after removing to strengthen the fibers. Might be overthinking things but..... The antenna had 4 screws holding it along with dicor. It was solid and I know a few limbs hit it over time.

[HMS_Beagle]

deltabravo wrote:

HMS Beagle wrote:
Just VHB tape, on a solid roof, will be stronger than a few #8 screws.

VHB tape attached to rubber roof membrane, with the rubber roof membrane being glued to the underlayment of the roof is a horrible idea.

On any rubber roof RV, the panels need screwed down to the wood under the rubber roof.

I'd agree that on a rubber membrane roof VHB tape is a bad idea. In fact a rubber roof is a bad idea, but that's another subject. That's why I said "on a solid roof".

[SoonDockin]

The Arctic Fox has a membrane roof. Tape alone is not enough in my opinion. I also don't believe there are any structural members in the roof. I believe its just a big sip (foam bonded to plywood on each side) panel. So based on the size of screws they use to hold everything down, I feel the 8mm should hold. Time will tell.

[rwynkoop]

I have had to remove mine. I wondered that same thing you did. I used the z mounts, but instead of mounting the solar panel to then, I mounted a square aluminum bar across then, then mounted the panel to the aluminum bar. Every thing is higher off the roof, leaving access to the nuts that secure the panels to the square bars. Been running this way for about 6 years now.