WD-716 'forward rib flanges'

Since this appears to be one of the most challenging parts of the build, I figured I'd better get this cleared up before touching anything

The manual says something like "When the forward ribs of the WD-716 canopy frame assembly are manufactured, the flanges are not 90 degrees. Use a file to remove some material from the aft edge of the upper flange so it is 90 degrees when checked with a square..."

Is this what they are referring to?



Thanks!

Thats what I did. Used a vixen file on the area between the hinge points and beyond about 4 inches each side.

You can also do some fluting on those flanges. The material is pretty thick there, but anything you can do to get the correct shape will pay dividends when you try to get the skin to lay flat. The fore and aft braces that are welded to the tubing need to be filed down flat.

Taildrgr said:

Thats what I did. Used a vixen file on the area between the hinge points and beyond about 4 inches each side.

Click to expand...

What was throwing me off is that those flanges are almost exactly 90 degrees as-is (you can sort of see the square laying pretty much perfectly on the rib). This is why I thought maybe they meant some other part.

I followed Bruce's suggestion to do a little fluting and those holes line up perfectly with the skin. Now the aft hole alignment with the tube centerline...that's going to need some work!

Luis

Here's what I did.

If you place a straight edge on the top of the WD-716 frame assembly between the forward channel and aft round tube you see what I saw.



The skin is not going to lay flat on the forward upper channel flange?

I used my belt sander as seen in image 2 and 3. The aft round tube is elevated flush with the height of the belt. Then, just slide the frame side to side to remove material from the aft edge of the upper flange, just like the plans say to do.





As a result of removing a bit of material from the Wd-716 upper flange, aft edge, we now have a flange that's in the same plane as the aft round tube. The Canopy skin will now fit nice and flush on the flange.

Use caution and read ahead on this portion. I read then followed instructions, but most documentation only finds and corrects the issues later. One for me was issue that the instructions says to put the forward skin and tip skin on and pull down tight in order to locate the center patch/splice. (Notice that the previous poster had some cleco clamps along the bottom rail. That is not the best location.) Then pulling down the skins tight it depresses the center of the canopy frame and allows the leading edge of the skin to deflect upward. Be sure to align the skins with a long straight edge when you perform this step as the natural result would be about .030" low in the center. It is a result of a poor contour match with the forward portion. Further, it will cause portion outboard of the hinge to pucker up causing further issues. Others call them "wings"

PM me as you go and I will share my experience if you wish. I am not an expert, but have had to address a lot of issues, may of which could have been avoided. Happy building!

Related to what Bill Lane is saying.

Clamping the Splice Plate flange to the canopy frame lower channel flange resulted in an altered and undesirable fit of the canopy frame. The frame would bow outward and be to wide.



Ultimately I clamped the splice plate as seen below. This makes adjusting the canopy frame width easier.