I finally got around to installing one of the two vents I bought on Ebay for my Hunter Shadow Teardrop. The vents I bought were 9"x9" and can be seen here.
The first job was to cut a hole in the top of the Teardrop. I started by locating the cross beams of the roof and aligning the vent so the front holes could be drilled into a cross beam. The side and back holes would need wood braces installed in order to have something to screw into. When cutting the vent hole (I used a jig saw) make sure of three things:
1) Your jig saw blades (metal blade for the top, wood blade for the interior) must be short enough not to bang into the other surface. I put the blades in a vice and tapped them with a hammer to break off any unwanted length.
2) Be sure not to cut through the electrical wires that run right down the center of the trailer and feed the hatch and license plate lights.
3) Use masking tape or newspaper to protect surfaces from being scratched by the jig saw.
I cut the top hole first (metal blade for aluminum) and used that hole to drill holes through the interior wood, and cut that hole second (wood blade). Be sure to line your cuts on the wood with masking tape to prevent unwanted splintering. Here's what the top hole looked like:
The insulation went all the way across, so I removed the square so you could see the wires. One reason the Hunter Teardrops get so hot in summer is because they were made for hunters in the Rocky Mountains and were therefore thoroughly insulated to stay warm in fall and winter. Needless to say, I pulled out all the insulation from the compartment I was working on. I have also consider taking the hatch apart and removing all the insulation from it as well.
Here's a picture after cutting the interior hole (through wood), and installing the gasket. It wasn't quite the type gasket I was looking for, but I made do with an inexpensive door gasket from Lowes. I figured I was going to seal it with silicon sealant anyhow - besides, the gasket had adhesive on one side which made it very easy to work with. I rubbed silicon gel on the gasket after placement. (NOTE: the vent directions say to use "putty tape" for the gasket, but I knew that would dry out and crack very quickly, so I went with the rubber door gasket).
Note also I had to splice the wires and add some length in order to re-route them around the vent hole.
You may not be able to see from the picture, but I had to install braces on both sides of the vent in order to have something to drill into. These pieces had to line up with the holes, and I didn't want them moving when I drilled the holes, so I attached them to the crossbeams with wood glue. The wood glue will probably dry out some day and give way, but once all the screws are in, the vent will be solid. The toothpicks were just to check drill hole alignment before actually installing the vent.
Here's what the inside of the vent looks like after adding the garnish plate:
This picture also shows off the LED strip I use instead of the old style light bulb that came with the Teardrop (and uses >100x the power for half the light intensity).
And finally, here is what the vent looks like from the outside before and after the silicon sealant was applied:
I could have done a better job sealing the screw heads, but it is what it is and I doubt seriously this guy is going to leak for at least 5 years.
I've decided to only install one of the two vents I bought, for a couple reasons:
1) I think one vent will be sufficient to significantly cool off the interior.
2) Unless you can build a platform to work on, this job can be very hard on your knees (at least it was mine). Standing on a small ladder and bending over to make precise cuts and drilling holes was tough on my knees.
3) I have a backup vent just in case some misfortune were to come to this one.
One last hint: when it comes time to seal the vent with your caulk gun, do the back or sides first - just to get the hang of it. The front seal is probably the most important (i.e. doing 80 mph in the rain), and I did it first before I had my shit together. Have some water and paper towels handy. Also, make a small cut in the caulking tube nozzle - it doesn't take much of a bead to seal the vent.
So that's it. Hopefully it will not only cool me off, but vent my exhalations while sleeping. I find myself in bear territory often and sometimes I am just not comfortable leaving the doors open. Now, I have a nice topside vent to pull air through the windows! Who-hooo!
Lastly, I finally made a very stable pod for my sealed lead acid (SLA) battery. I ended up using plumbers tape - flexible yet very rigid. The battery is held securely in the wood frame by three velcro straps. So, the battery is very easy to remove, yet is very secure even on bumpy backwoods roads.
If you have any questions, just leave a comment.