Adding Solar to 21RBS

[nhlakes]

Have not actually noticed what stuff is secured with up top.  #2 SS self taping square head make sense.   I'll check out Amazon.  I'd seen those housings.  Will check them out. thanks

[nhlakes]

anyone know if what is typically used is #8 or #10 or ?

https://www.amazon.com/Stainless-Tapping-Drilling-Bolt-Dropper/dp/B076C4QRLM

[Jonathan]

The flexible panel is working out great, but I have decided I'm going to add a 100wt tiltable panel to the roof.  I'll be able to leave it tilted toward the south in the driveway and will not have to wonder about it being covered with snow/ice.  I'll still have the flexible panel to move about when I'm really trying to charge while camping.

Any suggestions on securing the panel mounts to the roof and/or running the wire? I may leave the wire running on the outside for now and deal with that in the spring.

Here are the small tilt mounts I'll use.
https://www.amazon.com/gp/product/B07CSKFWK7

What would be optimal is if you could fasten into the Cross beams if the spacing is right.  Uni-struts would allow you to hit the cross members but it also raises your profile and wind resistance.  Those mounts will all the "millions" of holes are nice but (I know this isn't your first rodeo)  when you install butyl tape or butyl sealant and fasten the screws through it, reminder to ensure you completely cover all the exposed butyl with another polymer sealant.  UV will eat up the butyl through all those those little holes.  I work in commercial single ply roofing and we use caulk tubes of butyl sealant.

Note that the mounts are listed for smaller than 100wt panels but appears many people apparently use these for the 100wt panel
https://www.amazon.com/Renogy-Monocrystalline-Solar-Compact-Design/dp/B07GF5JY35

[nhlakes]

What would be optimal is if you could fasten into the Cross beams if the spacing is right.  Uni-struts would allow you to hit the cross members but it also raises your profile and wind resistance.  Those mounts will all the "millions" of holes are nice but (I know this isn't your first rodeo)  when you install butyl tape or butyl sealant and fasten the screws through it, reminder to ensure you completely cover all the exposed butyl with another polymer sealant.  UV will eat up the butyl through all those those little holes.  I work in commercial single ply roofing and we use caulk tubes of butyl sealant.

Thanks. Panel placement will be dictated by available real estate, so yes I could install a bottom bracket (what you are calling a uni-lever) to pick up the roof frame cross-members and attach the mount to that.  Considered that, but the roof is pretty thick and there is not a lot of force on the mount, so was hoping that would not be necessary. 

Would love to hear from others who have screwed into the alum roofs.

Have not thought much or researched sealant yet.  Do I need to use butyl in addition to sealant?
Already have some of this: https://www.amazon.com/Dicor-501LSW-1-Self-Leveling-Sealant-10-3-Fluid_Ounces/dp/B000BRF7QE

[Merlin]

nhlakes, I've had the A/C off the roof to install a new seal. On my camper the roof is a thick aluminum and in my humble opinion will hold the panel to roof securely if you use several #8 screws on each side like those you linked to. Other things on the roof like the antenna, vents, and skylight are just screwed into the the Al. I like the idea of Jonathon's to seal with butyl tape, but make sure you can get the screws torqued well enough. Cover it all with the Dicor self-leveling caulk you linked to. It's good stuff and has held down my cell booster wiring on the roof really well for a few years and lots of miles.

Important edit: SAFETY NOTE. There is wiring in the roof, both 120VAC and 12VDC !!!!!!!!!!!!!!!

Edit #2; Use fresh caulk. I learned the hard way that even unopened caulk I had sitting around for contingencies wasn't up to the task after a couple of years. Oops.

[stu1965]

What would be optimal is if you could fasten into the Cross beams if the spacing is right.  Uni-struts would allow you to hit the cross members but it also raises your profile and wind resistance.  Those mounts will all the "millions" of holes are nice but (I know this isn't your first rodeo)  when you install butyl tape or butyl sealant and fasten the screws through it, reminder to ensure you completely cover all the exposed butyl with another polymer sealant.  UV will eat up the butyl through all those those little holes.  I work in commercial single ply roofing and we use caulk tubes of butyl sealant.

Thanks. Panel placement will be dictated by available real estate, so yes I could install a bottom bracket (what you are calling a uni-lever) to pick up the roof frame cross-members and attach the mount to that.  Considered that, but the roof is pretty thick and there is not a lot of force on the mount, so was hoping that would not be necessary. 

Would love to hear from others who have screwed into the alum roofs.

Have not thought much or researched sealant yet.  Do I need to use butyl in addition to sealant?
Already have some of this: https://www.amazon.com/Dicor-501LSW-1-Self-Leveling-Sealant-10-3-Fluid_Ounces/dp/B000BRF7QE

I've read rather than screwing into the roof, you can use VHB tape - https://www.mobile-solarpower.com/solar-panel-mounts.html

[Merlin]

On my roof, the curve is too much to use tape, except for maybe very small panels between the A/C unit and the side.

[Jonathan]

What would be optimal is if you could fasten into the Cross beams if the spacing is right.  Uni-struts would allow you to hit the cross members but it also raises your profile and wind resistance.  Those mounts will all the "millions" of holes are nice but (I know this isn't your first rodeo)  when you install butyl tape or butyl sealant and fasten the screws through it, reminder to ensure you completely cover all the exposed butyl with another polymer sealant.  UV will eat up the butyl through all those those little holes.  I work in commercial single ply roofing and we use caulk tubes of butyl sealant.

Thanks. Panel placement will be dictated by available real estate, so yes I could install a bottom bracket (what you are calling a uni-lever) to pick up the roof frame cross-members and attach the mount to that.  Considered that, but the roof is pretty thick and there is not a lot of force on the mount, so was hoping that would not be necessary. 

Would love to hear from others who have screwed into the alum roofs.

Have not thought much or researched sealant yet.  Do I need to use butyl in addition to sealant?
Already have some of this: https://www.amazon.com/Dicor-501LSW-1-Self-Leveling-Sealant-10-3-Fluid_Ounces/dp/B000BRF7QE

The butyl sealant is a critical component to the sealing.  The butyl never cures and stays flexible and pliable and will stay that way through the expansion and contraction of the metal and keep the penetrations watertight.  If you only use sealant there is a risk of disbonding  and allowing water to migrate into the penetrations.  Just ensure that the butyl is completely covered with sealant as butyl will breakdown when exposed to UV.

[nhlakes]

The butyl sealant is a critical component to the sealing.  The butyl never cures and stays flexible and pliable and will stay that way through the expansion and contraction of the metal and keep the penetrations watertight.  If you only use sealant there is a risk of disbonding  and allowing water to migrate into the penetrations.  Just ensure that the butyl is completely covered with sealant as butyl will breakdown when exposed to UV.

I had honestly forgotten what the butyl was. I was thinking it was something else. Once I googled it, it was like 'oh, THAT stuff'. Yes, will use that as well. I had some on hand but not the right size.  Right size stuff arriving today.   Thanks!

[nhlakes]

Went to install the fixed panel yesterday morning and could not settle on location to mount panel. Turns out the best place to mount the panels is up front.  But unfortunately the front of the campers is shaded by a tree much of the time.  That's where the trailer is parked 99% of the time.

Now considering just returning the fixed panel and securing the flex panel someplace accessible, efficient, and where the snow will not build up.  Will package up panel and mount and ponder for a bit before sending it back.

[DavidM]

If the shading is at a permanent parking space at home, what is the problem. You will need very little actual solar power just to keep the batteries up. Then when you go camping someplace else the front location is as good as any, right?

But if what you are describing is a seasonal site where you actually camp then yes, a portable panel would be better. If you haven't bought one yet, consider SunPower's 170 watt flexible panel: https://www.amazon.com/SunPower-Flexible-Efficiency-Solar-Panel/dp/B07MLT3J15/ref=sr_1_19?crid=16XELT9U1DR5D&dchild=1&keywords=200+watt+flexible+solar+panel&qid=1606502786&sprefix=200+watt+flexible+sola%2Caps%2C171&sr=8-19

It is a 24V nominal panel which means lower voltage drop to your controller.

David

[nhlakes]

Yes, just referring to the parking spot in driveway.  I do get your point on that it would likely get enough sun in the shaded spot to maintain it, but would hate to drill holes and discover otherwise.  I already have the Renogy 100wt flexible. 

No hurry so I think I'll hold off on the drilling any holes. This whole solar thing is just for the fun of it for me, to experiment with solar.  It's not like we really need it for anything.  My GC batteries hold us for a few days with careful use - and I have a pair of Hondas if/when I need to charge or to run everything off grid.  It would just be cool to be more energy independent with the camper.

[AZCamper1]

Hmmn, this is the method I'm going to use to mount a flexible 110W Sunpower panel on my roof.  No drilling into the roof!
https://www.rvwithtito.com/articles/install-flexible-solar-panel-rv/  He does a follow up video.  I'm using Stainless elevator bolts.
All I'm trying to do is keep my sole 12v batt charged because where I store no power is available.
Small 10A Renogy PWM controller going to mount on panel left of furnace.  I ran 6awg wires down corner of dry bath, then through furnace compartment. 4awg lines to go underneath from compartment next to furnace to batty up front.  With this wiring, I can always upgrade if I really want to add panels, more batts, etc.

We get plenty of sun in AZ!   

[Merlin]

Hmmn, this is the method I'm going to use to mount a flexible 110W Sunpower panel on my roof.  No drilling into the roof!
https://www.rvwithtito.com/articles/install-flexible-solar-panel-rv/  He does a follow up video.  I'm using Stainless elevator bolts.
All I'm trying to do is keep my sole 12v batt charged because where I store no power is available.
Small 10A Renogy PWM controller going to mount on panel left of furnace.  I ran 6awg wires down corner of dry bath, then through furnace compartment. 4awg lines to go underneath from compartment next to furnace to batty up front.  With this wiring, I can always upgrade if I really want to add panels, more batts, etc.

We get plenty of sun in AZ!   

Welcome to the forum! Looks like you have solar figured out. Good work.