SonexBuilders.net

Hi guys,

I am working on my windscreen and want to know how you guys did yours. Did you install the bow and then match the windscreen to the bow? Did you set the bow to the 17 + inches on the plans and then match the windscreen to it?

I have a pre-cut screen and it is high and needs to be cut down. I need to cut about a half inch of each side in the front and don't know if I should carry that cut the full length of the side or if I should angle it.

Thanks for any help.

Peter

Hi Peter,

Trim the windscreen at the front carefully to fit the front flange.
Do not trim off the rear sides the same amount, so angle your cuts along the side.
You want maximum material across the rear bow.
You set the bow to the windscreen arch.
This avoids a dished look for the windscreen to canopy transition.

Following the above here is how mine came out...

I thought I'd mount the windshield one day and decided to get the best looking lines I would need to do other things first. I mounted the engine so I could fit the cowling. Then I used a straight edge or string along the top of the cowl to set the windshield bow to the height of that extended straight line of the top of the cowl. Then you can work the canopy to fit the remaining opening. That should give you that sleek Sonex shape.
Happy Landings
John
N50NX

When installing mine, pushed the bow up to make full use of the supplied Lexan sheet. Bow was about out with about 3/4" higher than plan for extra head room and forward visibility, and nice clean line with both the original Sonex canopy and the current Todd's canopy. Also glued a double later of black felt on the bow strap before installing wind shield which makes a bit of a seal to canopy.

David A.

As others have mentioned, use the full amount of windshield material at the bow and only trim the firewall section. You want maximum bow to avoid the porpoise nose look.

I followed the radius's on the plans. Viewed from the side there is a smooth transition from the windscreen to the canopy and no dolphin nose. Viewed from the front though, there is some dolphin nose lower down the sides. I doubt it is possible to eliminate the dolphin nose totally with a flat wrap windscreen.

Caution with the plans. The canopy radius is drawn outside radius, the windscreen bow, drawn inside diameter. Not noticing and making an error here places the windscreen bow real low and is possibly the main reason for dolphin nose. Sonex may or may not have altered the drawing since?

Steve
Sonex 892

Thank you gentlemen for you responses they have been very helpful.

Peter

Hey Guys, I have already done my rear windscreen bow to the plans and drilled it.
Have I made a mistake? Should I lay the canopy down to see if the lines will be good?
I notice some builders prefer to place the rear bow up some utilizing all of the material in
the blank windscreen sheet at the rear. I have just finished my motor to the point of doing the rear mount
and ignition stuff. I wanted to go ahead and get this done so I can get going on the cowling. I would have installed the windscreen
assuming it would look fine to the canopy. Should I look further down the road to have this all blend in?
Thanks, Mark

Have you cut the windshield? If you find the bow is too short, you can aways just put a new bow in. If you've cut the windshield, then you really are committed to the shape. It might be fine. And the porpoise nose look isn't bad, it just doesn't have a clean flow from cowl to turtle deck.

No, I have not trimmed the windscreen yet. But I do not want somebody saying Hey look at the porpoise nose on that...
That nose should come with a bowl of soup...Oh, it looks good on your plane though.
I was not aware of adjusting this area for optimun appearance. I know I spent a couple hrs fine tuning the bow to get a nice curve.
I got it from sonex cause I thought it might be better shaped than I might have done, but it kinda looked like it was just
formed around a tree. As I recall it also has a particular little bend at the bottoms where it transitions to the fuselage.
I am glad I caught this thread, now I know to look at the shape before I trim the windscreen.