Solar panel danger!

[serpa4]

I pulled my 150 watt panel and replace with two 435 watt panels.
I attached just like the factory one. The new panels do not extend beyond the search light on my C30.
Was going down the highway and both panel and the roof rack cross bars took off like a kit across the highway!!!
The cross bars have through screws in them, so I figured good to go. Well, those screws only hold the clamp itself together. It does not pass through the cross bars!!!
There is a tiny, non-pointed, set screw in the far side you cannot see that is the only thing holding the bars in place.

Check your set screws OR drill through the whole bar and secure with a bolt.
Only 4 tiny setscrews holding down the panels at highway speeds....lucky no one was behind me. They cleared the 4 lane highway and ended up on the other side!!!

 

[Pilotnavigator]

Get the tubes welded!

 

[Severum88]

Thanks for the tip! I will check mine as well. I now have two panels up there as well, but never checked how the bars are mounted and secured.

Severum

 

[scross]

Not sure if Cutwater or RT is still using them but my sports rack was fabricated by Bolton Stainless in Armstrong, BC. They have photos of their racks on a Cutwater at their web site.
https://www.boltonstainless.com/

 

[serpa4]

I'm not saying they are poorly built.
My boat did come with a 140 watt panel and I replaced with two 435 which are almost 4ft wide each.
I made a much larger wind scoop than the small factory one.
Perhaps the setscrews are fine as I have not heard of ANY stock boats with them blowing off.

 

[Severum88]

Thanks you for the tip! I checked the set-screws on my 2016 C26, and all but one were very loose. Suppose my whopping 14kt cruise rate on two panels weren't enough, but it would not have been long. Tighten up those set screws!

 

[serpa4]

Thanks you for the tip! I checked the set-screws on my 2016 C26, and all but one were very loose. Suppose my whopping 14kt cruise rate on two panels weren't enough, but it would not have been long. Tighten up those set screws!

I was going 60mph down the Highway and pushing a head wind.

 

[Osprey]

I have replaced most of the fitting setscrews with SS pop rivets. To drill the required hole in the tubing I used an Irwin bit designed for drilling hard metals. I learned this method from the person who installed the Bimini frame on my tug.

 

[BB marine]

I believe this was posted in a thread couple of years ago. When posted I checked the set screws on the pilot house roof rack and my Bimini top. Most of the set screws were tight a few were loose. I removed each set screw and used a I/8 titanium drill bit to drill a dimple in the the rail surface where the set screw anchors. This is a common practice in an industrial environment to insure a good surface contact for the set screw and helps eliminated the chance of them coming loose. I Also applied a small amount of locktite 242 ( blue ) to the threads. I have had no issues with the set screws coming loose that I did this to. Last summer we had a new cockpit enclosure made for our C26. The Canvas shop did a great job except for one item. Tightening the set screws that are used to attach the Frame work. We removed all the canvas and just had the frame work standing in place for road travel. Shortly after getting on the highway I looked back and saw what looked like the Bimini frame work hanging down on one side of the boat. My fear was It just scratched the side of the boat and it was about to be laying on the highway. I pulled over and found the rail hanging on because of a slight bind at the fitting connection. When I moved it to position it it fell completely off. There was no damage to the hull just the aggravation of installing the frame work on the highway. I did eventually dimple the rails and locktite the set screws.

 

[scross]

If you are going to replace the set screws by drilling through the tubes and then using SS rivets, I strongly suggest using 1/4” structural blind SS rivets. These are called CherryMax, Interlock® rivets, Kliklock® rivets, Ultragrips® rivets, and Magna-Lok® rivets. These structural blind rivets have a shear strength of 2,500 pounds and a tensile strength of 2,200 pounds. They are used in aircraft construction where strength is needed but access to back a solid rivet is not possible.
I am going the same rout as B. Brown with an added 45 degree 18” brace forward of the front sports bar. Will post photos when it’s completed.

 

[serpa4]

If you are going to replace the set screws by drilling through the tubes and then using SS rivets, I strongly suggest using 1/4” structural blind SS rivets. These are called CherryMax, Interlock® rivets, Kliklock® rivets, Ultragrips® rivets, and Magna-Lok® rivets. These structural blind rivets have a shear strength of 2,500 pounds and a tensile strength of 2,200 pounds. They are used in aircraft construction where strength is needed but access to back a solid rivet is not possible.
I am going the same rout as B. Brown with an added 45 degree 18” brace forward of the front sports bar. Will post photos when it’s completed.

If I rivet, will one be enough if I drill out the set screw? If I through bolt, it will have two sheer points vice one rivet.
But, rivets will be easier. If you rivet one side, then the bars can still be moved forward or backwards as the clam shells can still open. This is why I wanted to through bolt, so I can adjust if needed.

 

[scross]

If you riveted each leg of the sports rack with one SS structural rivet, it’s my opinion that it would be plenty strong enough given the strength of those structural rivets. But that’s my personal opinion based on my experience using them in airplane building. I am not an engineer.
I’m going with Brian’s idea and not riveting.
If you needed to move the racks and you used structural rivets, you could always just drill out the rivets.

 

[Osprey]

Removing the set screw and drilling one wall of the underlying tube is not difficult. This is what I have done. However, through bolting probably requires drilling a hole in the fitting wall. On another project I found that can be quite difficult. Been there, not going back. The single side, pop rivet method, has worked for me over a number of years of use - including divided highway towing speeds. Your experience may differ.

 

[scross]

Sports rack brace installed. Total parts cost about $100. Two hours work time. One foot of 1” railing with end attachments.

gallery2.php?g2_itemId=79376

Tubing partially drilled to provide more secure purchase for set screws. Original flat set screws on sports rack replaced with pointed SS set screws. Thread locker applied to all bolts and set screws.

gallery2.php?g2_itemId=79373

 

[serpa4]

Looks nice!
Mine cross poles are much shorter without a CB.

 

[scross]

Serpa4,
Thanks! I have a long and skinny (27” wide) 180 watt solar panel and Yakima cargo box on the sports rack now. But the brace was anticipating upgrading to a 42” wide 330 watt Panasonic HIT solar panel next season. With the wider panel I want to be sure it will stay put at highway speeds! I’m hoping the upgrade will move me from 52 Amp/Hrs per day currently to 95 Amp/Hrs day while still using my Victron 100/20 smart controller.

 

[Automaticman865]

I'm not sure of the set screws size. but I had built a ladder for my cw28 and did not like the set screws on the stainless brackets. I replaced them with 1/4-28 x 1/4 button socket cap screws. There is not no way I could strip out these unlike the tiny set screws. I also ground the outside edge of the threads giving it a slight point to dig in. Although they sit slightly above the bracket, they are rounded so that they look good and nothing snags on them.

Stuart