Air-O-Lite Window Seal & Gasket Replacement

 

The final product

With all the water damage in the Boles when I got it I knew I'd have to seal everything up as best I could. 70 years can do in the best window seals and there was some obvious leakage around the windows.

The windows in a 1948 Boles Aero are a brand called Air-O-Lite. I've read they used this brand for a few years. There are two panes per window with each pane tipping out at the bottom to provide airflow while deflecting rain if they are open. The sash and frame are aluminum channel. Each pane is held in place buy a small spring/hinge arrangement. They are easy to remove: 1) open the window; 2) remove the cotter pin connecting the window opener to the pane; 3) push the pane to one side and use a screwdriver to pop the spring/hinge out of the retaining hole on the opposite side.

Spring/hinger hanger. Push towards the pane to pop it out of the hinge hole in the frame

Exterior of pane. Two panes per window.

Interior of pane. Note center brace and small weld/solder joint in lover right corner

I wish I could say the panes are easy to remove from the sash. They may be but most of mine weren't. The dried out seal can act like glue.

I don't know the proper procedure, so I was making it up as I went.

I removed the center brace (2 screws) and then removed a screw on each lower side of the sash that hold the sides to the bottom. The sides appear to be soldered or tack welded to the bottom on the backside of the mitered corner. You need to break the weld joint to pull the sides and or bottom sash pieces off. The weld is not strong but it does hold the pieces in close alignment so you'll need to address it during reassembly. I used Gorilla Weld epoxy and it seemed to do the trick. I chose it over JB Weld because the set time is much shorter (10 minutes vs 4 hours) and the strength is nearly the same.

After breaking the first pane with some aggressive pulling,  I sprayed the remainder of the seals with WD-40 and let it soak in. This seemed to loosen them up and work much better, but still not great. There was one window with newer seals and those came out easily with a WD-40 spritz. Another one came loose after I broke the pane, but I literally had to use a bench chisel to get the hardened seal out.

Note: the broken original glass was 3/32" thick. My local glass shop didn't carry it so I went with 1/8" thick plain glass which is readily available. It fit fine when I installed it.

Pane before disassembly

Partially disassembled

One all the pieces were apart, I cleaned them up before reassembly. 

After letting them dry I placed the bottom 3 sash pieces outside face down on a flat surface and got them properly squared up. I reinstalled the small screw in each corner bracket. I cleaned up the corners with some denatured alcohol in preparation for the epoxy. Then I mixed a small dab of Gorilla Weld epoxy and applied it to the inside mitered corner where there had been a solder joint of tack weld.

Reassembled sash with pane sporting new seals

Gorilla Weld epoxy in the mitered corner

While the epoxy set I cut the new seals. I got mine from VintageTrailerGaskets.com (search on Air-O-Lite). They sell a seal and gasket combo that replaces the original seal. You may be able to get the original at VintageTrailerSupply.com but they were out when I was ordering. I think the separate seal and gasket from VintageTrailerGasket.com is a little more flexible and useful because the integral gasket on the original design  is not useful between the two panes, however with a separate gasket you can locate it so that it seals the space between the panes when they are closed.

The seals are 45 degree miter in each corner. I slid the panes with seals in place into the sash. Here's an understatement: this is tricky and frustrated me immensely. This step will be impossible if you don't lubricate the seal-sash before attempting. I used a liberal application of DuPont Teflon Silicone Lubricant Aerosol Spray which seemed to work well.

Reassembled pane

After the pane with new seal was assembled I wiped it down with denatured alcohol and then cut and placed the gaskets in appropriate locations.

Gasket installed - this is an upper pane. A lower pane would have no use for the gasket at the top

I took the opportunity with the panes out to clean the window surround and scrub off the rust from the screws that had stained the aluminum. I replaced the rusted screws with stainless truss head screws. In my never ending attempt to keep water out, I dipped the point end of each screw in some Sikaflex sealant before treading them in.

Rust stains from screws

Much better

I chose not to pull the entire window frame after close inspection of the areas around the windows. The factory seal was holding strong and there was no evidence of past leakage so I decided not to disturb it.

A few updates:

• The box score on breakage was 8-5-1: I saved 8 panes, broke 5, and found one already broken in the corner. I'll call that last one a draw. The long ones from the front and back of the trailer were most difficult to save (I was 2-2 on those). 
• I suggest removing the sash in this order as it seemed to be slightly better at limiting breakage: long U-shaped top rail, one side rail, long bottom rail, final short side rail. Removing the long rail last nearly always led to a broken pane for a variety of reasons.
• The panes in my windows were 8"x22 3/4" and 8"x32 3/4". If you have the same you might want to get a couple from the glass shop before you start so you can complete your weekend project. They aren't expensive.
• I had one pane that had no rubber seals but was puttied into place and the putty was rock hard! I put it aside till last. I ended up following a window experts glum advise: chisel it out. Fortunately I have a set of "bench chisels" (ie used for all sorts of tasks) so I didn't have to sacrifice one of my nice wood working chisels. Interestingly this was a pane I didn't break, mostly because I had lots of experience since I'd saved it for last.