Strip across the top of a tip up canopy

Can anyone tell me what the name of the strip of aluminum or fiberglass that people put across the back side of a tip up canopy. It covers the area that closed on the roll bar? Also, does anyone have instructions to make one? Unfortunately I was unaware that the tip up cannot be left partially open on startup and I snapped a piece off at the tip I will use "weld on 3 " to reinstall it but would like to have the strap on to insure that it stays there. Thanks.

Lots of folks call it a "Targa" after the similar item on the Porsche 911



Actually a really old word meaning "shield"

I leave my tip-up partially open on start-up with no ill effects, other than an annoying rattle.

I always close and latch my tip up before starting or shutting down. My I0-360 shakes like a wet dog! I will taxi with it partially open though.

I did a 4 layer layup of fiberglass for my targa strip. Just rough up the plexi good where you want it to stick and wax where you don't. Some people run the screws through the targa strip too but I couldn't come up with an easy way since my plexi was already machine countersunk.

How do people seal any gap left under the Targa strip when the canopy is closed? My -6 tip-up doesn't have a targa strip but the plexi from the tip-up portion overhangs the roll bar and sits very close to it when closed and locked. Unfortunately, not close enough to avoid air leaks, and an annoying whistle that starts around 170mph...

I made a targa strip with the help of a friend who is talented in fiberglass work. It actually was very easy. Here are pictures of the operation. Most important was the ability to raise the temp in my hangar to at least 75F for curing. It was done in January.
We covered the area with duct tape first, then did the layup over the duct tape and removed it for trimming and sanding. I spotted 6 of the mounting holes for #6 ctsk screws. Later we roughed up the plexiglass, applied resin with flox and clecoed the strip in place for curing. Screws with nuts were added last and screw heads painted white.
Hope these pictures work and help.

http://s1115.photobucket.com/user/kens9/slideshow/RV-9 Targa Strip

Snowflake said:

How do people seal any gap left under the Targa strip when the canopy is closed? My -6 tip-up doesn't have a targa strip but the plexi from the tip-up portion overhangs the roll bar and sits very close to it when closed and locked. Unfortunately, not close enough to avoid air leaks, and an annoying whistle that starts around 170mph...

Click to expand...

In your case, you could apply a very thin weather-strip to the roll bar to close the gap. Most people lay a targa strip up directly onto the closed canopy and rear canopy. The layup is prevented from sticking to the rear canopy with packing tape and/or wax or release agent. The resulting layup conforms exactly to the rear canopy and, at least in my installation, no air whistles through.

I did a slider, but it should be pretty easy to make the strip out of metal.
It would be similar to the metal strip I put over the front of my sliding canopy or over the windscreen/roll bar.
I started with the holes pre-drilled through the plexi and canopy frame. I laid some heavier weight packing paper over the canopy where I wanted my fairing to be and stuck clecos through the paper/plexi/canopy frame to hold the paper in place.
I measured a set distance fore and aft (width I wanted the fairing to be) from each cleco and made a dot. I connected the dots with a slightly flexible ruler/ freehand and I had a half moon shaped pattern to transfer to some aluminum sheet. I used .032 for most of it and .040 above the windscreen, .032 was easier to conform to the bends.
After cutting the aluminum to the pattern shape I drilled one hole in the top (I used 2 seperate pieces to save on material) and clecoed it to the canopy assembly. Using hand pressure and duck tape positioned the fairing where I wanted it and used a hole finder to drill the holes working from the top to the bottom.
If you search my build log some of this is in there, good luck!

http://www.vansairforce.com/community/showthread.php?t=94648

flion said:

In your case, you could apply a very thin weather-strip to the roll bar to close the gap. Most people lay a targa strip up directly onto the closed canopy and rear canopy. The layup is prevented from sticking to the rear canopy with packing tape and/or wax or release agent. The resulting layup conforms exactly to the rear canopy and, at least in my installation, no air whistles through.

Click to expand...

Mine had a piece of 1/16" to 1/8" adhesive-backed foam weather stripping on it when I bought it... It seemed to fit fine across the top, but on the vertical sides the sliding action as the canopy opens/closes just destroys the weather stripping, leaving you with exposed double-sided tape... And that's just annoying.

I was thinking about filling the back of the "C" channel on the canopy with 1" thick soft (spongy?) foam... It could then seal against the front face of the roll bar when closed. The trick will be to find the right thickness so that the foam maintains enough pressure with the roll bar to maintain a seal, but doesn't stick out so far that it gets ripped off when opening/closing the canopy...

Thankfully we go through a lot of large pieces of packing foam like this at work, so finding a scrap piece big enough to make a one-piece insert for my canopy might not be that hard.

boom3 said:

I always close and latch my tip up before starting or shutting down. My I0-360 shakes like a wet dog! I will taxi with it partially open though.

I did a 4 layer layup of fiberglass for my targa strip. Just rough up the plexi good where you want it to stick and wax where you don't. Some people run the screws through the targa strip too but I couldn't come up with an easy way since my plexi was already machine countersunk.

Click to expand...

I did exactly as Jeff, only rough up the plexi really good as my first attempt did not adhere too well. Fortunately I was still during construction phase and had not painted it. My lay up was offset by about 1/8? to avoid the lip. This has been working really good to keep the rain and a bit of wind out since it overlaps the back side.

Templates

I have templates for the tip up. Glass will work fine but I think metal is a little more durable. I made mine from .032 and Sika'd them onto the glass. The lower portion was blended to the side skirts with fiberglass.

There is some air leakage that can be reduced with thin weather stripping or filling the gap with silicon sealer after the painting is done.

My fiberglass targa strip made the canopy much stiffer and most of the whistling noise has been eliminated. I don't think an aluminum strip would add any stiffness. One of the major advantages is that rain does not flow in any more.

Targa

Thanks for all of the great advice. Now it's a matter of doing it.

Sika

How difficult would it be to layup a targa that integrates into the side skirts, that first releases, then I could come back with SikaFlex to get an even better bond? I've heard of epoxy letting go in some cases over time. Building in the spacing for the Sika seems it could be a slight challenge without making this piece too bulky.