Online Community of Zenith Builders and Flyers
It is not a "spar" but a tube. See drawing C75-FA-9. There would be no way to put nuts on the bolts plus there would be poor airflow over the bolt heads.
Rivets can be used That is what I did. 10 years, 950 hrs, still holding up fine.
Jimmy what I was trying to ask it appears the screws at the front edge of the top window go thru the bracket but do not hit the tube going across. I wonder why not use a screw with a nut on the end thru the Lexan?
If you could post a photo of what you are talking about it will help. The only fasteners I am aware of go thru the windshield and skylight & straight into the cabin frame tubes. I think I recall the plans show self-tapping screws furnished with the kit. That is where I elected to go with rivets. My thinking was, the odds of ever having to remove the windshield or skylight are low, and even if that need were to come up, drilling out rivets is no big deal anyway.
To answer your question, I would go with weight. The screws are plenty adequate to hold the windscreen securely, I've never heard of a windscreen departing a high-wing Zenith in flight. They go directly into the cross tube, first through the trim piece, then through slightly oversized holes in the Lexan to allow for a plastic bush sleeve so the metal screw does not directly contact the Lexan. Add a small bead of sealant across the top before you do the final install or it will leak rain badly- if you fly in rain- I don't :)
Jim I tried to post a photo but my internet is so slow was going to take 20 minutes I know there is a way to reduce the size but don’t know how
Jim the screws in the top of the trim piece going into the top window will not reach the cross tube the asngle is wrong!!
Jim I don’t think the screws or rivets from the sky;light/top window will reach the carry thru tube the angle is wrong will try to load as picture
In photo, you have the top window trim piece wrong side out. See drawing C75-FA-9, exploded view on left side of drawing about 2/3 of the way down. The crease in the trim piece goes towards the inside of the cabin not outward like shown in photo.
Yup, flip that channel over Louie! And note the drawing, one side is wider than the other for a reason.
Jim I noticed that after i send the picture. What I wanted to ask what do the screws at the top of the trim piece go into. Do they just screw into the trim piece and then screwed into the Lexan doesn't seem you would get a secure connection that way?
Here is a couple photos how I did it. Used 4-40 stainless screws.