I purchased two Kyocera KD185GX solar panels a while ago not thinking it would have taken me as long as it did to get to this stage in the build. In the interim they have just been sitting around getting dusty while the prices for solar panels have been dropping. D'Oh.
The panels are each 52-3/4" x 39". There are four mounting holes on each long side for 5/16" bolts. According to the installation instructions these are the only holes to be used for bolting down the panels. If I was to run bolts straight through those holes into the penthouse top they would penetrate into the living space. That raises the possibility of a leak inside the van. Have to think of something else.
I've read that Sportsmobile installs their solar panels by using 3M VHB tape to stick the panels to the roof. I gave that some thought but decided against it. One person has already posted about how their panels flew off the roof while traveling on the interstate when the VHB tape failed.
So I'll have to come up with some way to bolt them to the roof but outside of the canvas penthouse. This is the view with the penthouse raised. You're looking up underneath penthouse top with the canvas on the left.
Here's a closer view. Notice the ridge to the right of where the canvas meets the penthouse top. This marks the edge of the wood reinforcement that's embedded inside the fiberglass when the penthouse top was constructed.
If I'm going to run any bolts through the penthouse top they will have to be aligned so that they are outside the canvas but penetrate the wood reinforcement for strength. That gives me about 1-1/2" to work with on each side of the top.
I'll insert a warning
disclaimer here. From what I've read the different Sportsmobile franchises use different types of penthouse tops. Also the tops have changed over the years. So everything I'm writing here only applies to my top
. Yours might be totally different.
Measured the penthouse on top and it's about 56" across but it's edges are not straight so the width varies. With the panels mounted cross-wise that leaves about a 1-1/2" for a custom made bracket to extend beyond the edge of the solar panel. This way the panel is bolted to the bracket and the bracket is bolted through the penthouse top.
Make the brackets out of 1" square steel tube. Two of the brackets will be shared between two panels so I'll need six total. Made them 14" long which allows me to cover both mounting holes but still have extra room for moving them back and forth for the final fit.
The panels will be bolted through the square tube but I'll add a piece of 2" angle iron to the end for the bolt through the top. Here I'm eyeballing the angle iron along with a 5/16" bolt trying to guess what would be the best width. Settled on 1-1/2"
The six brackets with the angle iron welded to the ends. You can't see it in this picture but the angle iron is positioned so that the bottom edge of the square tube will be raised above the level of the roof. This is to provide clearance for the bolt heads that will extend through the tube.
With the brackets made I had a better idea of the dimensions involved. Double checked my figures then did the deed. Drilled through the roof from underneath.
Took my time. This drill bit has a sharp point. When the point started to protrude I stopped drilling from underneath.
Finished drilling the hole from above. Did this as a precaution to prevent splitting on the fiberglass top.
No backing out now.
Measured the thickness of the top at the hole. Thought the info might come in handy later. It did.
Using the distance from the front edge of the top as a guide I drilled a corresponding hole on the opposite side of the top. Now to get the distance between them. Put a bolt thought each hole and measured.
Transpose that measurement to the brackets on the solar panel. It should be 55-9/16" to the outside edge of the bolts.
Use clamps to hold the brackets tight to the solar panels. Reach in under the lip of the panel and use a sharp screw to etch the outline of the mounting holes onto the bracket.
Drill two holes in the bracket. Use them to bolt the bracket to the panel.
Check the measurements again. Etch the other bracket and drill it.
Bolt both brackets to the solar panel and hoist it to the top of the penthouse to check my measurements.
Well I'll be. The holes line up.
At this point it was getting late and it was supposed to rain the next day. So before quitting I got the remaining epoxy bought for waterproofing the greywater tank.
Mixed up a small batch and used that to coat the inside of the bolt holes. If water should get into the wooden core of the penthouse top it could cause problems. Hopefully this will prevent it. Did this three times for each hole I put through the top. Allowed the epoxy to fully set up between applications.
Covered the two holes with duck tape.