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Discussion Starter #1 (Edited)
I've been mooching information from you guys long enough, figured I'd give back with a bit of a guide on how we solved the need of mounting 2x 300W panels to the roof of our 159WB EXT.

Parts Required
  • 2x - 10 ft., Low-Profile, Slotted, Black Powder-Coated Steel Strut Channel ($38.08 / each) (Link)
  • 8x - Vantech® H45-46 - Top and Bottom Adapter Kit ($33.49 / each) (Link)
  • 8x - 3/8"-16 Strut Channel Nuts, Stainless Steel ($3.72 / each) (Link)
  • 8x - 3/8" Square Strut Channel Washers, Stainless Steel ($3.69 / each) (Link)
  • 8x - 3/8"-16, 1-1/4" Long Hex Head Screws, Stainless Steel ($7.27 / 25) (Link)
  • 8x - 3/8" SAE Washers, Stainless Steel ($10.07 / 50) (Link)
The idea here is you attach the Vantech adapters to the nubs already on the roof, bolt the roof rails to these adapters, then use strut channel hardware to mount the panels to the rails.

I measured center to center on the rails, then took that measurement to the solar panel frame. This required us to drill 8 new holes in each corner of the solar panel frame, but the holes landed in a very good spot between the outer edge of the frame and the first hole provided from the factory.

Hardware is tucked up inside the solar panel frame and goes like this, from top down:

  • Hex Head Screw
  • 2x - 3/8" Round Washers
  • Solar Panel Frame
  • Square Channel Washer (Sitting on TOP of the rail to help distribute the load.)
  • Strut Channel Nut
Using a ratcheting offset box wrench is best to get to the bolt since accessibility is limited. As you tighten, the strut channel nut will get pulled up against the inside of the rail, sandwiching all the hardware together and pulling the solar panel down against the square washer and flat against the roof rail. It feels VERY secure and allows for tight clearances. We fit ours between a Maxxfan AND a Mini Heki roof light that is centered above our bed area. We thought panels this large wouldn't fit in this spot but this got it done. We are super pleased.

Pics Below













GIFs
 

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Very nice and exceptionally clean looking install! I know the roof is a bit convex and I had to raise my panels up a bit to clear it. How much clearance does this mounting system leave between the panel rails and the roof?
 

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Discussion Starter #3
Very nice and exceptionally clean looking install! I know the roof is a bit convex and I had to raise my panels up a bit to clear it. How much clearance does this mounting system leave between the panel rails and the roof?
Thanks!

Yeah the roof has more of a curve that you'd expect! I don't have the van nearby to run and take a measurement but there is maybe about half an inch between the upper edge of a roof rib and the lower edge of the panel frame. Maybe less? The rails solved the issue of the roof curve perfectly and the panels are still lower than the fan and the skylight in their lowest positions, which is idea. They make no wind noise at all, surprisingly.

To elaborate on how we landed here: We initially bought the panels with 2 sets of Renogy brackets because it just seemed like the thing to do. We quickly realized that the brackets wouldn't lift the panels high enough to deal with the curve of the roof over such large panels. The brackets would also require drilling new holes in the panel frame (not really an issue), as well as drilling a lot of holes in the van roof (also not really an issue, but less ideal...) -- we didn't know how to deal with installing brackets in the middle between the two panels, and we didn't know what method we'd want to use for actually screwing the brackets into the roof. (Self-tapping screws only? VHB tape? Rivnuts?)

Ultimately it was important to me to be able to remove a panel for cleaning, replacement, other modifications to the roof, wiring, etc. so mounting the panels to "something else" (i.e. a rail) started to make the most sense, even though it was an expense I hadn't initially considered. My wife reminded me it's worth doing important things the right way. There are other places to save a buck.

All told it wasn't a bad investment because of how easy and painless the install is. We are planning to get a Thule awning down the road too, so now we have the ability to remove the panels if they interfere with our awning mounting solution. Great peace of mind. :)
 

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I like what you did here. The low profile Unistrut is a great idea.

I am thinking of doing the same thing but having a front and rear cross support too. I am thinking that if I did this I could maybe just use the bottom bracket portion of the Vantech roof adapters. This would sandwich the roof pin between the Vantech bottom bracket and the Unistrut. The side to side supports and switching which way each bracket slide on the pin would keep it from sliding apart (i.e. slide the Vantech bottom bracket in from the left on the forward pin, in from the right on the next one back and alternate each one from there). Is there really a reason I need the top cap of the Vantech bracket? Cost is less than $10 for just the Vantech bottom bracket and almost $35 for the set of the bottom bracket and the top cap.

Thx again for sharing your build.
 

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Scalawag, great post! Few questions for you:

Do you have any pictures of the solar panel frame, and the holes you drilled there?
Which solar panels are you using.
Did you have any issues with the spacing of the Unistrut holes (which I would assume is P4100T) and the Vantech bracket?
Do the roof rails have any play, or do they feel rock-solid?
Seconding ScottWood's question, the top bracket seems to be used just for load spreading across the rubber surface rather than all the weight going through the little roof pin.

Thanks
 

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Discussion Starter #6
I like what you did here. The low profile Unistrut is a great idea.

I am thinking of doing the same thing but having a front and rear cross support too. I am thinking that if I did this I could maybe just use the bottom bracket portion of the Vantech roof adapters. This would sandwich the roof pin between the Vantech bottom bracket and the Unistrut. The side to side supports and switching which way each bracket slide on the pin would keep it from sliding apart (i.e. slide the Vantech bottom bracket in from the left on the forward pin, in from the right on the next one back and alternate each one from there). Is there really a reason I need the top cap of the Vantech bracket? Cost is less than $10 for just the Vantech bottom bracket and almost $35 for the set of the bottom bracket and the top cap.
[TRIGGER_ATTACHMENT][/TRIGGER_ATTACHMENT]
Thx again for sharing your build.
These instructions may illustrate why that might not be the best idea. I'm not one to shy away from an intelligent alternative but I suspect that you don't want to be loading those top edges of the bottom piece without some additional load distribution - even if that comes in the form of a separate square washer or something similar.

57934
 

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Discussion Starter #7
Scalawag, great post! Few questions for you:

Do you have any pictures of the solar panel frame, and the holes you drilled there?
Which solar panels are you using.
Did you have any issues with the spacing of the Unistrut holes (which I would assume is P4100T) and the Vantech bracket?
Do the roof rails have any play, or do they feel rock-solid?
Seconding ScottWood's question, the top bracket seems to be used just for load spreading across the rubber surface rather than all the weight going through the little roof pin.

Thanks
1) Wish I had a better picture, but unfortunately I don't. This is a picture of the first hole we drilled (that we properly screwed up) — definitely want to match the factory alignment of the hole because you'll never be able to use a tool on the hardware if you put the hole too close to the interior of the panel frame. Lesson learned on this one. I cut down a large fender washer to help fudge the mistake. The rest were easy after figuring that out. This gives you a general sense of the holes position though.

2) No issues at all. Everything miraculously lined up in a logical way. There were enough slots in the rails that we were able to tuck the first adapter stud flush up against the edge of the first slot in the rail and just go from there. Even for studs that ended up in the middle of a slot, we used washers on all of them so it was inconsequential. Really can't stress that this wasn't a big deal at all. P4100T looks to be about the same spacing arrangement we had on ours.

3) They are super-duper rock solid. Yanking on them with all my strength caused the van to rock on its tires. We live in Philadelphia and frequently drive on horrible pot hole roads and cobble stones and nothing up there is moving at all.

4) I think you could probably get creative in finding another way to distribute the load from the rail across the |_| shape of the bottom part of the adapter, but with the upper part of the adapter you are spreading the load from the rail (and the compressive force of the fasteners) down all the way to the surface of the van roof. That's a lot more solid than putting say a washer on top of the bottom adapter piece or some other workaround. It likely could work, but it might not be where I'd save money - and I love saving money. :)

57935
57936
 

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Are you doing a 24v system?
I like this set up a lot but I'm not having any luck finding solar panels wide enough for the roof that are 12v and from a reliable brand.
 

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Discussion Starter #9
These are 2, 24V panels wired in series for a total of 48V. The solar charge controller steps the 48V down to 12V for use in the solar system.
 

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Nice Setup, I looked at doing this with strut but went with 8020 and associated parts etc from DIYvan in Hood River Oregon. Nice folks up there. His setup keeps the panels flush with the top of the 8020, for a super clean low profile install. It's on the pricy side, but I guess I like the look of 8020.

They also provided the vent spacers, floor insulation for my build etc.
 

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Hey guys,

For anyone doing this rack in Canada:
CariD has insane shipping costs for the VanTech mounts (see below)
The VanTech website doesn't ship to Canada.

However, if you call VanTech (631 486 9303) then they can ship to Canada at a very reasonable rate (I think my order was $180 + $25 shipping).

58165
 
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