I got a message the other day from Ron Southard with a question about the windshield frames I'd used on NX1279. We decided this might be a good subject for the forum in case others were interested in the process.
The pictures shown below were taken several years ago during the restoration of a TravelAir and the windshields I used on my Hatz were just scaled down versions of this design.
Whatever curved shape you intend to use, first make a paper then aluminum pattern to develop the shape, roll and installed angle of your windshield. The ones I built for NX1279 are a little bit shorter than optimum for a wind free cockpit, particularly in the front. The trade offs are appearance, drag and cockpit access.
In any case, once you've developed your curved windshield pattern, you'll need to build a form that matches your curve to use when heating and drape forming the plexiglass. I'm pretty sure that process has been covered elsewhere in the forum so I won't get into it. I took my pattern to a local guy who has some expertise in plexiglass forming and he supplied the material and formed them for a reasonable cost.
Once you've got the formed plexiglass, you then start laying out the frame pattern using paper as shown below.
- 2.jpg (12.53 KiB) Viewed 6992 times
- 3.jpg (6.97 KiB) Viewed 6992 times
- 4.jpg (37.89 KiB) Viewed 6992 times
You have to make separate patterns for the inside and outside since the thickness of the windshield changes the radius.
To reinforce the frame, I formed a length of 3/16" aluminum rod to match the contour of the back edge, then made my frame pieces long enough to extend around the aluminum rod and meet on the centerline of the back edge. You can also use aluminum tubing. Tubing is easier to weld to, but doesn't offer as much reinforcement.
- 5.jpg (34.18 KiB) Viewed 6992 times
It's hard to make out the picture of the rod, but trust me it's in there.
Use a soft hammer to start forming the frame pieces around the rod.
- 6.jpg (19.87 KiB) Viewed 6992 times
I got a message the other day from Ron Southard with a question about the windshield frames I'd used on NX1279. We decided this might be a good subject for the forum in case others were interested in the process.
The pictures shown below were taken several years ago during the restoration of a TravelAir and the windshields I used on my Hatz were just scaled down versions of this design.
Whatever curved shape you intend to use, first make a paper then aluminum pattern to develop the shape, roll and installed angle of your windshield. The ones I built for NX1279 are a little bit shorter than optimum for a wind free cockpit, particularly in the front. The trade offs are appearance, drag and cockpit access.
In any case, once you've developed your curved windshield pattern, you'll need to build a form that matches your curve to use when heating and drape forming the plexiglass. I'm pretty sure that process has been covered elsewhere in the forum so I won't get into it. I took my pattern to a local guy who has some expertise in plexiglass forming and he supplied the material and formed them for a reasonable cost.
Once you've got the formed plexiglass, you then start laying out the frame pattern using paper as shown below.
[attachment=4]2.jpg[/attachment]
[attachment=3]3.jpg[/attachment]
[attachment=2]4.jpg[/attachment]
You have to make separate patterns for the inside and outside since the thickness of the windshield changes the radius.
To reinforce the frame, I formed a length of 3/16" aluminum rod to match the contour of the back edge, then made my frame pieces long enough to extend around the aluminum rod and meet on the centerline of the back edge. You can also use aluminum tubing. Tubing is easier to weld to, but doesn't offer as much reinforcement.
[attachment=1]5.jpg[/attachment]
It's hard to make out the picture of the rod, but trust me it's in there.
Use a soft hammer to start forming the frame pieces around the rod.
[attachment=0]6.jpg[/attachment]