Aluminium extrusion for solar mounting

[California Dreamin]

We have been using a 100w flexible panel with a victron MPPT for some years. The panel is not as good now as it was a few years ago and I have replaced it with two 100w panels which will be used in series to double the voltage and make it easier to create the 5v difference between the battery and the panels needed for charging to start each day. Until now I have just propped the panel up at 45 degrees against the bumper to catch the sun when we are camping and left it on the inside of the windscreen when we are home. This has worked well but with two shiny new panels it feels a bit precarious. I am therefore considering roof mounting them. I know solar solutions have a kit - but we don't need this as we have 90 percent of whats needed already.

Any tips for roof mounting (on a beech) from anyone who has done it themselves already. Soecifics like what size penny washers to fit in the roof rails, what size unequal aluminium extrusion is ideal and good places to source it? Any tips or words of wisdom?

 

[yossarian]

Any tips for roof mounting

I've replaced my corroded scs hardware with these: https://www.ebay.co.uk/itm/114122262791?var=414380955751 I used M8 but M6 might be preferable.

https://www.ebay.co.uk/itm/314304014335?var=612945484263 (10mm M8s)

Bent sheet aluminium plates are popular with our Continental cousins. See https://shop.automobile-hess.ch/category/solar-blech-ohne-solarzellen-und-elektronik-vw-t5-i

I'm not sure of the logistics of having these made here especially as these are bent to match the contour of the roof.

 

[California Dreamin]

I've replaced my corroded scs hardware with these: https://www.ebay.co.uk/itm/114122262791?var=414380955751 I used M8 but M6 might be preferable.

https://www.ebay.co.uk/itm/314304014335?var=612945484263 (10mm M8s)

Bent sheet aluminium plates are popular with our Continental cousins. See https://shop.automobile-hess.ch/category/solar-blech-ohne-solarzellen-und-elektronik-vw-t5-i

I'm not sure of the logistics of having these made here especially as these are bent to match the contour of the roof.

Thank you so much. I didn't realise that unistrut fixings were the right size - that's ideal. I agree - M6 will be plenty. I like the euro curved panels but want to finish the job for under £100 from here in so looking for. decent supplier of anodised black unequal angle. Guessing that 25x12 would probably be a reasonable size and low profile enough to allow a bend but avoid catching the wind too much.

 

[yossarian]

I had to discard one spring and could only find 316 Stainless with the long spring. But I'm happy with the result.

 

[California Dreamin]

I had to discard one spring and could only find 316 Stainless with the long spring. But I'm happy with the result.

Is the long spring not needed then - i.e. could get away with short? How about these: https://www.orbitalfasteners.co.uk/...annel-nut-stainless-steel-unistrut-compatible

or the short: https://www.orbitalfasteners.co.uk/...ible?queryID=a3cfb94fc5a40c3e725db1bfff3f1498

 

[yossarian]

I'd go for the short spring (but haven't tried it). Removing the spring if necessary is child's play. The springs did make the job slightly easier except where I wanted to route a cable.

A flanged screw might work better too.