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Slider Canopy Frame Screw Up

grayforge

Well Known Member
Arrggghhhh!

I was attempting to bend the slider canopy frame lower rail (the box section) to conform to the shape of my fuselage. I guess I shouldn't have clamped one end in a vise between a couple boards and pried on the other end... I ended up kinking the section. See the attached photos.

So what's my best bet? Should I swap the canopy frame out for a whole new one? If replacing the whole frame is overkill, what's the best fix for this?

I also sent an email to Russ McCutcheon, who fabricates these...

Thanks,
Russ

DSC03639.jpg


DSC03637.jpg
 
Thanks for posting? very timely, one side of mine is 1/4 off where the pin goes into the block and I was trying to figure out how to get that bend.
 
The options I see are

1. Cut it out and weld in a new section of stock
2. Take a strip of steel, and have it welded over on all sides like a bridge to help stiffen it back up.
3. Fill it and build on (not sure how much the strength of it is compromised)
4. Replace it

If it were me, I'd probably go with option 4. 1 and 2 will be more effort and probably cost than replacing. 3 may compromise the structural integrity.
 
I replaced the frame after kinking the front bow. The C.O.D.shipping cost more than the frame. I suggest a repair if possible.
 
Sorry to see your problem
been there done something similar! Payed way to much for shipping. Don't know if I would try for a repair. Mostly I would order a new frame but make sure Vans uses the LEAST costly shipping. Not much fun in making a $400 - $500 error and ending up with close to $1k mistake. My error was chasing a lower gap at the roll bar. Suggest working with what you have no trying to make biggish changes to the frame.

Bottom line shipping cost is a killer if your tracking the total cost of your RV smile.
 
Hello Russ,

Can’t tell if you’ve kinked the frame or just dented the inside face of the box there ? That inside face will be covered by the C-791. Might give the C-791 a test fit and see what you think ? If it is just a cosmetic dent rather than a true structural kink, you might be good to go.

pk
 
An idea

Since it appears that is it is an expensive part with an expensive shipping cost associated with it, I would recommend trying a repair.

Here is my idea:

Drill a hole in the center of the ding. Hole diameter should be sized to accept a number 8 sheet metal screw threaded into the steel. With the head of the screw protruding above the box tubing of the frame, attempt to cry the screw out of the hole using a pair of diagonal cutting pliers or any other arrangements that gives you leverage. Hopefully since I believe the box tubing wall thickness is rather thin, you might be able to pull the ding out further. It will not be perfect and the whole can be welded up. The paint will be damaged during the welding process and we'll have to be touched up. If successful this will be for cheaper then total replacement including shipping charges.
 
DON'T DRILL A HOLE YET!!

Yes you will have to pull that dimple out, but go to a body shop and get their stud welder and put some studs on there and use a slide hammer to (try) pull that "dent" out. Being high strength, it may not work without being quite hot. Having used the drill/screw/hammer/pliers method, I like the stud welder much better. Several studs can be combined to cover larger area too.

Disclaimer, this may not work at all due to high material strength, but may be less messy than drilling puckering and welding up the holes. You can weld, pull, cut grind, then put another stud close to the last one in the process.

Good Luck, I welded up several predrilled holes in my tip up canopy frame that did not match the skin.
 
I had a series of these dents on both sides of my canopy frame in the RV-9A. This was required to get the shape required to fit my fuselage.

They get covered up later on in the process. Don't panic, build on.
 
Last edited:
An idea

Since it appears that is it is an expensive part with an expensive shipping cost associated with it, I would recommend trying a repair.

Here is my idea:

Drill a hole in the center of the ding. Hole diameter should be sized to accept a number 8 sheet metal screw threaded into the steel. With the head of the screw protruding above the box tubing of the frame, attempt to cry the screw out of the hole using a pair of diagonal cutting pliers or any other arrangements that gives you leverage. Hopefully since I believe the box tubing wall thickness is rather thin, you might be able to pull the ding out further. It will not be perfect and the whole can be welded up. The paint will be damaged during the welding process and we'll have to be touched up. If successful this will be for cheaper then total replacement including shipping charges.
 
Thanks for the ideas guys. After taking another look this morning with fresh eyes, I don't think it's as bad as I first thought. I decided to try to bend it back a bit to see how it went. This time, I put the bar across a couple 4x4s and used a dead blow hammer to work it. Ended up with right about the amount of bend originally intended.

The bar is quite strong, even with the ding in it. I figure the existing strength, plus a few layers of aluminum sheet and plexi and it'll be perfectly fine.

The rest of the bending process nearly drove me crazy. The canopy frame really does have a mind of its own. Bend one spot and another area randomly shifts. I prefer assembly where the parts fit right off the bat. But it's shaped properly now. I guess 8 hours of work isn't bad.

Here's what the kink looks like now:
DSC03642.jpg
 
Thanks for the ideas guys. After taking another look this morning with fresh eyes, I don't think it's as bad as I first thought. I decided to try to bend it back a bit to see how it went. This time, I put the bar across a couple 4x4s and used a dead blow hammer to work it. Ended up with right about the amount of bend originally intended.

The bar is quite strong, even with the ding in it. I figure the existing strength, plus a few layers of aluminum sheet and plexi and it'll be perfectly fine.

The rest of the bending process nearly drove me crazy. The canopy frame really does have a mind of its own. Bend one spot and another area randomly shifts. I prefer assembly where the parts fit right off the bat. But it's shaped properly now. I guess 8 hours of work isn't bad.

Here's what the kink looks like now:
DSC03642.jpg

Good job Russ!
 
I had a series of these dents on both sides of my canopy frame in the RV-9A. This was required to get the shape required to fit my fuselage.

They get covered up later on in the process. Don't panic, build on.

Good point, the canopy skirt brace will cover this.
 
Van's has come a long ways with this frame. I bought my finish kit in January, just finished the canopy, guess what, I did not have to do any manipulation of the canopy frame!
 
Van's has come a long ways with this frame. I bought my finish kit in January, just finished the canopy, guess what, I did not have to do any manipulation of the canopy frame!

Russ M, can you chime in with any changes you've made to welding the canopy frames? IE, Jig or process changes? I'm wondering if there was a change that made the latest frames fit better or if Bret just got lucky. :)

I'm guessing the latter since there can be a large variation in fuselage dimensions.

Thanks!
Russ
 
Russ M, can you chime in with any changes you've made to welding the canopy frames? IE, Jig or process changes? I'm wondering if there was a change that made the latest frames fit better or if Bret just got lucky. :)

I'm guessing the latter since there can be a large variation in fuselage dimensions.

Thanks!
Russ

There has been lots of changes over the years trying to get these more consistent but still no two are exactly the same, so yes luck could play a part in how it fits out of the box.
 
The only place where i can see a difference in fuse to fuse is the longerons. I bought the Dies to form the curves and it matched the curve in the bottom box section of the frame, the top curve front and rear were perfect also. I took some shots of the alignment on my build site if you care to look. :D
 
The longeron shape can differ as well as how far apart they are. The QuickBuild kits seem to come wider than standard. Mine is.

The width differing might then change the shape of the upper aft skin. Everything's related :)
 
The longeron shape can differ as well as how far apart they are. The QuickBuild kits seem to come wider than standard. Mine is.

The width differing might then change the shape of the upper aft skin. Everything's related :)

I did a survey of aircraft a few years ago and found up to 1" variation in fuselage width at the roll bar station.

Those with narrower fuselages had to bend the roll bars, but the canopy frame fit well. With wider fuselages, the roll bar was easier, but the canopy frame usually had to be cut and welded.

I spoke with Gus about this and I recommended that the QB fuselages be jigged at the roll bar station. I don't know if this has been fixed or not, but if reports are that the canopy is fitting well are true, things are looking up.
 
I'm definitely in the "Roll Bar Fit Out Of The Box", but "Canopy Frame Needed Lots Of Tweaking" camp.
 
Kinky frame

When I was building my 6a I too slightly kinked the frame when bending. I decided it was not a big deal tried best to slightly straighten it and went on!
 
Ask Van's. I slightly kinked mine (bow) just before a Sun 'n Fun. At the show I asked Van about it. Van: "no crack?" Me: "Nope." Van: "Bondo is a wonderful thing!" Bottom line is that it was not a structural issue, cosmetic only.
I suspect you will get the same answer, but send them the photos and let them advise.
 
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