When fitting mounting brackets to the solar panel frame, is it better to use a metal screw or bolt and nut? Looking at ease of removal if necessary for any reason. Also what size screw or bolt/nut. As the frames are aluminium should the fasteners be aluminium as I hear s/s corrodes aluminium??? TIA for all and any help.
Bas
Peter_n_Margaret said
09:40 AM May 26, 2018
The brackets are best attached to the roof via Sikaflex.
To secure the panels to the brackets I avoid screws because they fall out on corrugations. :(
Even with nuts and bolts I would always use nyloc nuts for security.
For convenience for removal, using some form of captive nut (or bolt) can sometimes be useful. For one installation I used hinges along one side of the panels and small over centre latches on the other side.
I have not had any issue with mixing s/s and aluminium.
Cheers,
Peter
Bas + Eve said
11:02 AM May 26, 2018
Thanks Peter
T1 Terry said
01:32 PM May 26, 2018
We used rivet-nuts and stainless 4mm bolts. Aluminium rivet-nuts in aluminium and steel in steel or where we need the added thread strength of steel so they can tighten extra tight. Self threading screws are only tight in their threads on a single use, once removed the same screw can not be reused nor can the same hole be used because the thread has been distorted on the original tightening process, that is how they stay done up. Once that distorted screw thread is pulled back through the aluminium the originally cut thread will be stretched and distorted and can not offer the same holding power as it did in the original application.
T1 Terry
-- Edited by T1 Terry on Saturday 26th of May 2018 01:34:19 PM
Peter_n_Margaret said
04:22 PM May 26, 2018
T1 Terry wrote:
We used rivet-nuts and stainless 4mm bolts.
Yep, good solution, that is one of the "captive" solutions I referred to, but I would add a locking washer under the bolt head...... and I use M6 nuts (in aluminium or steel) because that is what I have.....
Cheers,
Peter
Bas + Eve said
05:11 PM May 26, 2018
Would rivnuts be suitable if I choose to use the ABS solar mountings? IE will the ABS be strong enough to hold the rivnut? Ie the ABS solar mount will affix to the aluminium panel frame with 5 rivnuts. I am looking at the 680mm which mount on each end of the panel. Hope I have not confused you.
Bas + Eve said
05:38 PM May 26, 2018
Please ignore last post. After much thought I asume the rivnut would go into the panel frame and the bolt and washer through the ABS and into the rivnut.....
T1 Terry said
01:46 PM May 27, 2018
Peter_n_Margaret wrote:
T1 Terry wrote:
We used rivet-nuts and stainless 4mm bolts.
Yep, good solution, that is one of the "captive" solutions I referred to, but I would add a locking washer under the bolt head...... and I use M6 nuts (in aluminium or steel) because that is what I have.....
Cheers,
Peter
Seems you can't always edit a post to fix a stuff up.
Peter is correct regarding the 6mm stainless bolts and using flat washers and spring washers or a pair of the ratchet type lock washers. I thought my second edit had fixed the mistakes but I did neglect to read through it makes sure it read 6mm and not 4mm.
Aus-Kiwi said
10:05 PM Jun 3, 2018
Ours has rubber lining over 7 ply . We used stainless screws with plenty of Siko in, under and over screws and bracket.. The L alloy section is Siko and pop riveted to solar panel.. I also Siko and riveted a < strong plastic section on front outside so any tree branches or low elect, Telstra Arial cable wont get caught ..
Reed said
03:27 AM Aug 25, 2018
We place a 75 to 100 cm long x 2 cm thick aluminum stripping on the inside of the frame, drill through frame and stripping before we bolt each bracket to the frame. This prevents the bolt ripping through the thin aluminum frame with high wind stress.
Our 315 W panel was ripped off by high cross winds while transitting the Isthmus of Tehuantapec (the narrow waist of Mexico). These winds are world famous and the Isthmus seems to contain most of the wind farms in Mexico. The year before 5 semis had been rolled on one day by these winds near the aptly named town of Las Ventos. Winds have been clocked at 200 kmh. The highest point is about 200 m with mountain ranges that are 3 km or high on either side. So a high pressure in either Pacific or Caribbean with a low pressure on the other creates the winds.
Tied and taped the panel to rear of Roadtrek (we have a 6 m Roadtrek and an 11 m 5th wheel - Roadtrek can handle colonial Mexican towns). We got comments at Mexican gas stations along the lines of "how is that solar panel working back there?" since much of Mexico uses solar. My canned answer was "should work great going north but not that well headed south!" as we were headed to Yucatan.
To secure the panels to the brackets I avoid screws because they fall out on corrugations. :(
Even with nuts and bolts I would always use nyloc nuts for security.
For convenience for removal, using some form of captive nut (or bolt) can sometimes be useful. For one installation I used hinges along one side of the panels and small over centre latches on the other side.
I have not had any issue with mixing s/s and aluminium.
Cheers,
Peter
We used rivet-nuts and stainless 4mm bolts. Aluminium rivet-nuts in aluminium and steel in steel or where we need the added thread strength of steel so they can tighten extra tight. Self threading screws are only tight in their threads on a single use, once removed the same screw can not be reused nor can the same hole be used because the thread has been distorted on the original tightening process, that is how they stay done up. Once that distorted screw thread is pulled back through the aluminium the originally cut thread will be stretched and distorted and can not offer the same holding power as it did in the original application.
T1 Terry
-- Edited by T1 Terry on Saturday 26th of May 2018 01:34:19 PM
Yep, good solution, that is one of the "captive" solutions I referred to, but I would add a locking washer under the bolt head...... and I use M6 nuts (in aluminium or steel) because that is what I have.....
Cheers,
Peter
Seems you can't always edit a post to fix a stuff up.
Peter is correct regarding the 6mm stainless bolts and using flat washers and spring washers or a pair of the ratchet type lock washers. I thought my second edit had fixed the mistakes but I did neglect to read through it makes sure it read 6mm and not 4mm.
Our 315 W panel was ripped off by high cross winds while transitting the Isthmus of Tehuantapec (the narrow waist of Mexico). These winds are world famous and the Isthmus seems to contain most of the wind farms in Mexico. The year before 5 semis had been rolled on one day by these winds near the aptly named town of Las Ventos. Winds have been clocked at 200 kmh. The highest point is about 200 m with mountain ranges that are 3 km or high on either side. So a high pressure in either Pacific or Caribbean with a low pressure on the other creates the winds.
Tied and taped the panel to rear of Roadtrek (we have a 6 m Roadtrek and an 11 m 5th wheel - Roadtrek can handle colonial Mexican towns). We got comments at Mexican gas stations along the lines of "how is that solar panel working back there?" since much of Mexico uses solar. My canned answer was "should work great going north but not that well headed south!" as we were headed to Yucatan.
Reed and Elaine