Door skin question

[Grant4ever]

My series 7 has upper lexan window and lower non window door skins. I would like to replace with all lexan window skins. Can this be done with one piece or do I need to use two pieces?

I would like to avoid the very expensive bubble doors if possible.

Also, I probably need to keep the the old skins for templates. Can I re-attach the new lexan with less rivets? Sure looks like they get attached with less rivets in photos that I have seen.

Additionally, do the skins get drilled/riveted while the door is hung/latched in position?

Any thoughts and info on new door skins (windows) appreciated.

[HighWing]

Grant,
I Built a IV but think the door profile is pretty similar. I think without some significant heat forming which is very challenging with lexan it would be impossible to use a single sheet for upper and lower skins. In the IV kit, there was a piece of shaped fiberglass that served to cover the joint between upper and lower skins. I found it to be not quite the shape is needed to be and riveting it in place resulted in a scalloped sort of puckered edge.

Like you I wanted upper and lower lexan skins but with a more esthetic joint. On the internet, I found some H channel used in window framing and by filling the groove top and bottom at the bend area with thin aluminum strips, I was able to bend it with no distortion to the channel to fit the contour of the door. Trimming the lexan at the joint took some trial and error cuts, but it worked. I did the outside trim after I had fitted the joint area and clecoed the sheets in place. I suspect the technique would work on a SS door as well.

[shawnspeak]

Grant,

I'm just working through this process now on my series 5 which had lexan upper and fiberglass lower. I'm using a single sheet of 0.093" acrylic instead to avoid the fuel issues with lexan.

Here are the steps I followed:


Drilled out the rivets and carefully removed the old lexan/fiberglass skin.
Used the old skin as a template to rough cut the acrylic sheet. I left about 1/8" excess along the top of the door and 1/4" excess along the sides and bottom.
Installed rivnuts in some of the existing rivet holes to later secure the skin with #6 screws.
Used the old skin to drill the two holes in the acrylic for the hinges.
With the hinge holes drilled, I bolted the new acrylic onto the frame and drilled out the screw positions across the top of the door frame.
Sanded the top until I could get the frame/skin hung back on the plane.
Then, working from top to bottom, I trimmed/sanded the skin until it fit within the door recess. Drilled and installed screws as I went.
The acrylic will bend over the door, although there is quite a bit of stress there. So used a heat gun to slowly heat up the areas near the bends and remove the stress.
Final sanded everything till it fit evenly in the door recess.
Just like the bubble door installation, I used 3M 06382 Acrylic Attachment Tape to secure the acrylic to the frame in addition to the screws.

Few things I've learned about working with acrylic along the way:


Check out the EAA videos on Drilling acrylic http://www.eaavideo.org/video.aspx?v=1200008869001
Holes in acrylic should be ~10% bigger than needed to account for expansion.
Make sure to debur and smooth out all edges. The slightest nick in acrylic can leave a stress riser.

I'll be finishing this project tonight with the installation of some weather stripping and will take some pictures to post back here.

shawn b.

[KFfan]

Shawn,
EXCELLENT first post. Thanks!
Very well laid out point by point and easy to understand and follow. :cool:

[shawnspeak]

Here are a couple of pics just after I taped/screwed the skin on the frame

[bumsteer]

Lowell

I'm using "h" channel like you used in this earlier post. Wondering what you used in the channel for sealing the joint. Thanks.

Rick

[HighWing]

Rick,
I didn't put anything in the H channel. I guess I didn't think of it for a couple of reasons. The first being that with the original design with aluminum on the bottom - used on my first IV - and the Lexan on top there was nothing between the Lexan and the fiberglass closeout panel specified in the plans. And second in out climate we rarely have rain except during winter months and those are typically no fly days. Thinking about it, though, I wonder if some rubber U channel might be able to be trimmed so it doesn't extend above the H channel and provide a snug fit next to the acrylic or lexan.

[bumsteer]

Just ordered some narrow rubber u channel from ACS. Will see how it works. If it doesn't might try RV sealant.

Rick