Fixing semi-flexible solar panel

[ghostlymoron]

My only comment is what is a Bigfoot fitting?

 

[LittleSister]

My only comment is what is a Bigfoot fitting?

Oops! My error. I meant BigHead!

 

[scrambledegg]

None of us can know exactly the geometry/ properties/quality/flatness of the substrate that you hoping to attach your panel to,
but here's a few queries I would have.
* If you have good surface flatness on your roof I'm not sure that I can see the benefit of butyl sealant under the panel. There may be benefit in sticking the panel down for the reasons you say, but any thickness of sealant will allow the panel to depress under loading (foot, knee I mean). Must be pretty difficult to get an even layer of sealant
* It looks like a bighead fitting will sit proud of the roof a bit and therefore stress the panel at the places the panel passes over it.

 

[ithet]

I followed advice of previous threads and used 3M dual hook tape, really strong.

 

[LittleSister]

None of us can know exactly the geometry/ properties/quality/flatness of the substrate that you hoping to attach your panel to,
but here's a few queries I would have.
* If you have good surface flatness on your roof I'm not sure that I can see the benefit of butyl sealant under the panel. There may be benefit in sticking the panel down for the reasons you say, but any thickness of sealant will allow the panel to depress under loading (foot, knee I mean). Must be pretty difficult to get an even layer of sealant
* It looks like a bighead fitting will sit proud of the roof a bit and therefore stress the panel at the places the panel passes over it.

It is to be fixed to the of a gelcoat finished GRP wheelhouse roof, which curves gently in a single plane.

You make good points. I would hope to keep the sealant to only around 2mm thickness. The wider base of the Bighead fitting is perhaps not much more, and the slightly higher bracing of the stud on the fitting I would hope to accommodate within the fixing hole in the solar panel.

But I'm very much open to dissuasion/persuasion!

 

[Airscrew]

4 s/s small self tappers from B&Q, one at each corner.
Only 5mm into the (slightly curved) hatchcover is enough.
3 years and no movement.

Also, I chose to use a thick rubber washer to keep the panel AWAY from contact with the hatchcover.
Wind hasnt budged it, and zero green buildup.

 

[ghostlymoron]

How did you attach the tape to deck/panel?

I followed advice of previous threads and used 3M dual hook tape, really strong.

 

[ithet]

How did you attach the tape to deck/panel?

Use the tape type SJ3550 which has a very strong VHD type adhesive which is suitable for outdoor use. It bonds directly to the panel, GRP deck. The tape hooks to itself.
I fitted six 25mmx50mm pieces, to the corners and centre of the long edges of the panel, then hooked the mating pieces onto those, finally pressing the panel onto the deck (hatch garage). The area were the panel is mounted has a slight ribbing but the tape bonded down fine. Note that this method does leave a slight gap under the panel due to the thickness of the tape, but that might help cooling the panel.

This is what I ordered:
https://www.amazon.co.uk/gp/product/B004AQOBS2/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

 

[ghostlymoron]

Ah, so self adhesive Velcro. It must be better now as I used some to secure my settee berth cushions which came straight off again.

 

[ithet]

No No No, NOT Velcro. It is made by 3M and many times stronger, both in the hooking action and the adhesive. The type I linked to is suitable for exterior use.

Also talked about on this thread (amongst others):
http://www.ybw.com/forums/showthread.php?428596-Deck-mounting-semi-flexible-solar-panels-(again-)