Anyone have experience mounting Solar Panels using "T" tracks

[Re-Pete]

I'm still looking for a good, safe way to mount 8, 100W solar panels to my roof. I was considering the VHB tape method, but I learned that 3M does not recommend it, nor have they ever tested adhering it to Bus Kote. In November I painted the center roof panel with a Bus Kote system (Aqua Prime, BusKote and Flexi Clear). Even though the Bus Kote appears to adhere very well to the aluminum skin Hy-Tech could not answer my VHB tape adherence questions nor have I found any personal testimonials. I have decided not to disturb the Bus Kote and to mechanically fasten my panels to the roof. To that end I'd appreciate some feed back as to using "T" tracks as a way of mounting my solar panels or PV Modules as some properly call them. I thinking of using a combination of VHB tape and solid "buck" rivets to fasten down the "T" tracks and then coating the side seams with a lap sealant such as Dicor. Then I could attach my panel mounts to the "T" tracks with some SS "T" bolts. All in all, my hope is to use fewer rivets (fewer holes) this way and disperse the load along larger portions of the roof. I'd love to here from anyone who has some personal knowledge and experience with this type of installation. I'd also Like to hear what type of "T" track you used, recommendations and the like, as I have no experience with it. Thanks.

[wulfraat]

My panels are going on 3 years with 3MVHB and Silkaflex 221. No problems. Solid.

That being said I wouldn’t use t-tracks. You’ll likely end up putting same or more more holes in the roof to mount the tracks vs just riveting the individual feet… and I think it would be harder to seal t-track mounting points water tight.

If you want to use mechanical fasteners I’d use silka flex over the individual feet, which you could mount to the roof using both 3M VHB and a single rivet for additional security.

Just my $0.02.

You can always add rivets after the fact (start with 3M VHB tape + silkaflex and then add rivets later if they are not rock solid…

[uncle_bob]

Hi

If the BusKote is the issue, just remove it in the area right at the foot. Then use the VHB. Way easier than riveting in a bunch of this and that. You will do some coating over the area either way.

Bob

[Re-Pete]

Originally Posted by wulfraat

My panels are going on 3 years with 3MVHB and Silkaflex 221. No problems. Solid.

That being said I wouldn’t use t-tracks. You’ll likely end up putting same or more more holes in the roof to mount the tracks vs just riveting the individual feet… and I think it would be harder to seal t-track mounting points water tight.

If you want to use mechanical fasteners I’d use silka flex over the individual feet, which you could mount to the roof using both 3M VHB and a single rivet for additional security.

Just my $0.02.

You can always add rivets after the fact (start with 3M VHB tape + silkaflex and then add rivets later if they are not rock solid…

Originally Posted by uncle_bob

Hi

If the BusKote is the issue, just remove it in the area right at the foot. Then use the VHB. Way easier than riveting in a bunch of this and that. You will do some coating over the area either way.

Bob

Thanks for sharing your personal experience and your advice. I'm still trying to figure out what's best for me. I'm curious though. What type of VHB Tape did you or AM Solar use? I called 3M and I asked about the VHB 4950 tape (one that I've seen recommended by others as the tape to use) and was told it was not rated for exterior use and definitely not recommended for mounting solar panels on an RV. I know they make several types of VHB. Maybe I was asking the wrong questions. Maybe I should have asked what VHB Tape is? Any additional info you guys can offer would be appreciated.

[wulfraat]

3M 4950. Designated for metal on metal fastening.

140lbs / sq inch straight pull adhesion and 25lb peel adhesion property.

4950 adhesion durability report:

https://static1.squarespace.com/stat...Durability.pdf

Data sheet:
https://3m.citrination.com/pif/000337?locale=en-US

Am solar page (1000s of installs with 4950)
https://amsolar.com/rv-mounting-accessories/91m-vhb

It is not exposed to the elements when you come over stop with silkaflex which both adds additional adhesion and very important waterproofing.

Do not use Dicor lap sealant over the feet, it can be good for water proofing but does not have the adhesion power of silkaflex.

As I mentioned if you want the full Monty use 3M tape and then drive a single rivet through the foot. Come over the top with silkaflex to seal off the tape and the hole you’ve just made in your roof.

5952 is an alternative 3M product that some use. This may be advantageous for bus kote roofing paint. You’d need to review the specs.

[Re-Pete]

Originally Posted by wulfraat

3M 4950. Designated for metal on metal fastening.

140lbs / sq inch straight pull adhesion and 25lb peel adhesion property.

4950 adhesion durability report:

https://static1.squarespace.com/stat...Durability.pdf

Data sheet:
https://3m.citrination.com/pif/000337?locale=en-US

Am solar page (1000s of installs with 4950)
https://amsolar.com/rv-mounting-accessories/91m-vhb

It is not exposed to the elements when you come over stop with silkaflex which both adds additional adhesion and very important waterproofing.

Do not use Dicor lap sealant over the feet, it can be good for water proofing but does not have the adhesion power of silkaflex.

As I mentioned if you want the full Monty use 3M tape and then drive a single rivet through the foot. Come over the top with silkaflex to seal off the tape and the hole you’ve just made in your roof.

5952 is an alternative 3M product that some use. This may be advantageous for bus kote roofing paint. You’d need to review the specs.

I can't tell you how helpful all of this is. I've actually already independently looked up and reviewed the tech bulletin and datasheet you were kind enough to link to and even though it was mostly over my head overall I was feeling pretty good about 4950, but I was worried at that point about it sticking it to BUS Kote. I did finally get the feed back from HY-Tech (makers of Bus Kote) today that I had called them about last week. They said, bus Kote will not come off and that if the VHB tape sticks to it I should have no worries. Yay!



I'm beginning to think my first mistake was calling 3M. Hahaha Seriously they scared me. Before that and since that I've had some significant testimonials from a number of RV owners several of whom are Streamers. I've also had several folks with no experience tell me that VHB tape was a terrible idea. In just the past few days I've had this very helpful and confirming information from you and another streamer who has already done almost the exact application I'm into. He also applied what I'm calling the Bus Kote system, (because it includes 3 products) and adhered solar panels using aluminum mounts and VHB covered with Sikaflex on the mount edges and covered all that with Eternabond tape. From everything I've read about the 4950 it will have no issue sticking firmly to the Flexi Clear (elatomeric) Coating over the also elastomeric Bus Kote.



So, I hear you that Sikaflex 221 is a better adhesive than Dicor. I've not used Sikaflex. My go to's have been Dicor as a lap sealant and Trempro 635 as an adhesive sealant, parbond as as a seam sealant, etc. Naturally the Trempro 635 is not self leveling. Is the Sikaflex 221 self leveling or are you suggesting both Sikaflex and Dicor?

[wulfraat]

Originally Posted by Re-Pete;

Is the Sikaflex 221 self leveling or are you suggesting both Sikaflex and Dicor?

Sikaflex is not self-leveling, but it's not hard to work with either. Mask the area around each foot before applying to get nice square lines. Do not use both products (dicor+sikaflex) - just use sikaflex 221 in white.

Sounds like Bus note forms a strong bond to the aluminum it is applied to. That was my only knowledge gap - have not worked with bus kote before so didn't want to assuming anything regarding it's bonding properties.

I've got allota panels and $$ up top. 3M tape so far so good!

[uncle_bob]

Originally Posted by wulfraat

......

I've got allota panels and $$ up top. 3M tape so far so good!

Hi

You and probably 99% of the rest of the folks with solar panels are depending on the 3M tape.

Bob

[Mollysdad]

GMFL has a lot of solar instals, so he'd be a good source.

[tjdonahoe]

Originally Posted by Re-Pete

I'm still looking for a good, safe way to mount 8, 100W solar panels to my roof. I was considering the VHB tape method, but I learned that 3M does not recommend it, nor have they ever tested adhering it to Bus Kote. In November I painted the center roof panel with a Bus Kote system (Aqua Prime, BusKote and Flexi Clear). Even though the Bus Kote appears to adhere very well to the aluminum skin Hy-Tech could not answer my VHB tape adherence questions nor have I found any personal testimonials. I have decided not to disturb the Bus Kote and to mechanically fasten my panels to the roof. To that end I'd appreciate some feed back as to using "T" tracks as a way of mounting my solar panels or PV Modules as some properly call them. I thinking of using a combination of VHB tape and solid "buck" rivets to fasten down the "T" tracks and then coating the side seams with a lap sealant such as Dicor. Then I could attach my panel mounts to the "T" tracks with some SS "T" bolts. All in all, my hope is to use fewer rivets (fewer holes) this way and disperse the load along larger portions of the roof. I'd love to here from anyone who has some personal knowledge and experience with this type of installation. I'd also Like to hear what type of "T" track you used, recommendations and the like, as I have no experience with it. Thanks.

.many use 3 m. ..and it works…I am not drilling any holes

[Re-Pete]

Originally Posted by wulfraat

Sikaflex is not self-leveling, but it's not hard to work with either. Mask the area around each foot before applying to get nice square lines. Do not use both products (dicor+sikaflex) - just use sikaflex 221 in white.

Sounds like Bus note forms a strong bond to the aluminum it is applied to. That was my only knowledge gap - have not worked with bus kote before so didn't want to assuming anything regarding it's bonding properties.

I've got allota panels and $$ up top. 3M tape so far so good!

Thanks, I appreciate the info, the hand holding and the encouragement.

[Malia20]

I have the 3M-Silkaflex solution as recommended by AMSolar. No problems with the feet-to-roof attachment. But I will say there was a recent thread from someone who lost a panel off the roof. The conclusion was the bolt (or plastic wing-screw) that attaches the panel to the foot was lost and caused the lost panel. I have checked mine several times and found they do loosen up. Since I do not think I will be tilting the panels I have replaced the plastic wing-screw with machine screws with nylock nuts added to the end. Those are not coming off. There is always a weak point...
Safe travels.
Fred