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Having difficulty getting canopy to fully latch closed. It can be done (from both inside and outside the plane) but is extremely hard to do. Anybody else experience the same problem and if so what did you do to rectify.

Tom Jones
Onex # 133
Tri gear
Engine TBD
Van Wert, Ohio

Can't you just file down the "dogs" on the latch a bit?

Here's a picture of my latch, which is not stock or Onex, just to illustrate the latches. Take a flat file and remove some material on the flat surface that engages the phenolic plate. File a little, test the latch, repeat until it's good, then rub it down with a scotchbrite pad.

I've done some filing but am beginning to wonder if the nylon washers called out in the plans are a help or a hindrance. Has anyone tried conventional washers over and under the slide versus the nylon ones?

Ryan has a great description of what to do - I just did this last week and it only took a few tries to get it right. Removed a bit of material at a time, reinstalled and tested it.

thomasjones42 wrote:I've done some filing but am beginning to wonder if the nylon washers called out in the plans are a help or a hindrance. Has anyone tried conventional washers over and under the slide versus the nylon ones?

I'm not that familiar with the onex stock setup, but if the aluminum slide has any motion against a conventional (steel) washer, that washer will eventually grind away at the softer aluminum.

I spent a LOT of time filing down my latches to get them to latch well when fabricating them, then I installed the canopy, and then again had to do a lot of filing to get it to latch properly. I think I spent more time filing those latches than any other single part on my plane. Unless you're really concerned about not being enough material left on the latch (for strength), just keep filing away.

My latches were so tight that I did not install the plastic pads under the longeron. I have also added some foam stick on door sealer to stop the drafts where I did a bad job of matching the windshield bow. And I added another 1/2 inch square foam door sealer to the bulkhead under the rear edge of the canopy. That cut down the cold air in the winter so my manifold heater could keep the cockpit decent. Oh, I also closed up the bulkhead behind the seat and added a door to the upper opening. The profile of the canopy causes negative pressure in the cockpit and cold air is sucked in from the openings in the tail. After 70 hours the canopy latch is loosening up. I may have to add the fiber pads. Something else that helped the slide. I found some 1/2 inch wide silicone tape and applied it to the contact points of the slide. Aluminum sliding on aluminum doesn't work well.

File two notches on longer tabs. One for taxi for cooling and one for secure "take off" mode. Tom Flagg N179ES AeroVee