On our bus, built light angle iron frames and riveted and glued them down. A mate who has a caravan, used aluminum angle, welded them together before fixing them to the roof with rivets and epoxy glue. He tried sikaflex and wasn't happy with the results after a year or so as they started to come off, the same as we weren't happy when we used it on our motorsailer to cork her. Would have used aluminum for our frames, but not didn't want the outlay to get gas to weld them, so used very light angle iron and its been there for years. Caravans I reckon would be better to use aluminum.
I have 2x 120 Watt panels that are pop rivited together and i used 25mm aluminium that was pop rivited to the roof of my caravan. Cable run through the roof and in to the solar controler that was mounted in the cupboard and onto the house battery. Pop rivits every 100mm.
Hard part was drilling the hole for the cable in the roof. Contacted the manufacture to find out were the wireing is in the roof.
4 x 200 what panels on sort of roof racks gives about 70 ml air gap to help keep them cool the mounts come down the side of the van about 100 ml with 2 bolts holding each side .
I just installed an additional 80w solar panel (all up now 200w) using 50mm x 50mm aluminium angle.
This gives a good air space between the panel & the roof as well as a good area for a good coverage of sikaflex to hold the angle to the roof.
NO rivets at all. No rivets = no holes to leak.
The 2 solar panels that had been pre installed were glued only. They have been there for several years & seen some rough country in strong winds & are still very secure.
Good luck.
Many vans have a floating roof sheath in that the aluminium is fixed only to the outer edges of the van and at penetration points such as hatches etc.
If you simply glue or pop rivet your panels to that floating aluminium, then you have a good chance that movement will cause the sheeting to fatigue and tear.
The main problem with those individual panel corner mounts is that you are unlikely to get good fixing to the under structure should you need to do so.
Better to use sign channel or similar to bridge between solid fixing points thus ensuring that the panels don't cause damage to the roof membrane.
HI SNOW T WE USED AS PER EBAY 2 SETS CNRS AND SIDE MOULDS , GOOD SET UP BUT REALLY GOOD ALLY ANGLE AND GOOP , ETC PROBALLY JUST AS GOOD ,WE GOOPED AND SCREWED OURS DOWN JUST TO BE SURE
When I installed 2x80Watt panels on my old Millard, which had a curved roof line, I used 2x75mm aluminium channel strips down each edge of van then 2x75mm lengths going across van to raise above roof bow. I then mounted panels to them. Cross members screwed to van edges. Used an 240VAC electrical/through wall connector to feed cables through roof. Did over 10,000km around Central Qld. and no problems.
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Cheers Peter and Sue
"If I agree with you we'll both be wrong"
No, I'm not busy, I did it right the first time.
Self-powered wheelie walker, soon a power chair (ex. Nomad)