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Cracked canopy glass during magneto troubleshooting, can’t catch a break :(

S

SwimmingDragonfly96

Well Known Member
Seems like the mechanic accidentally slammed my canopy shut and caused a huge crack at the edge of it. It’s starting to get overwhelming dealing with all these issues, but it is what it is. Any advice on what I can do to fix this as much as possible? Builder recommended I stop drill it and add an aluminum fairing. I bought some canopy guides and lagged on installing them. Painful mistake.

PS, they couldn’t figure my ignition issue.
 

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Is this that same mechanic?
And he's standing behind damage that happened at his shop... NOT?
Insurance claim?
 
blaplante said:
Is this that same mechanic?
And he's standing behind damage that happened at his shop... NOT?
Insurance claim?
Click to expand...

No this is the on field mechanic in Carlsbad. He said he’d stop drill it and make it right if it continues being an issue. Not sure what he means by make it right.
 
Close to the edge

It appears to be within 3/4” of the aft edge of the canopy. That will be a big chunk to lose. Heat expansion may cause it to crack anyway.

A new canopy is easily $2,000 and about 200 hours of labor. I would start having that conversation with him right now. If he cracked someone’s Cirrus windscreen he would be replacing it.
 
Synergy?

Synergy is located in Eugene and they are a build assistance center. They may be willing to take on this kind of repair. If so they might be able to give you an idea of the time requirements and cost.

It is not just take the old one off; there will be adjustments to get it to fit, fiberglass work on the forward edge, paint. It will take awhile.

Sorry. I don’t mean to add to the problem.
 
sahrens said:
Synergy is located in Eugene and they are a build assistance center. They may be willing to take on this kind of repair. If so they might be able to give you an idea of the time requirements and cost.

It is not just take the old one off; there will be adjustments to get it to fit, fiberglass work on the forward edge, paint. It will take awhile.

Sorry. I don’t mean to add to the problem.
Click to expand...

Do you think it's bad enough to get the whole thing replaced?
 
First sorry to hear of incident, broken canopy is heartbreaking.

Replacing canopy is not an easy job and you will have to paint and match paint which might not be as easy.
Your other option is to use Weldon 3 first and then stop drill it to keep it from growing. Then you can create a faring from fiberglass or carbon fiber which is much easier than aluminum to cover the crack. There are many RV with such fairing. The FG or CF fairning will give the broken part some added strength that hopefully will last a life time. My RV7A had a such fairing not because it was cracked but because I liked the looks of it.
 
That crack should have already been drill stopped. How many other little hairline cracks are there you can't see. Yes it should be replaced, yes the mechanic should make it right by covering the costs of the replacement and repairs and yes it should be replaced because you are going to see that ugly crack every time you go flying and it it is just going to cause you to get upset again.
 
SwimmingDragonfly96 said:
Seems like the mechanic accidentally slammed my canopy shut and caused a huge crack at the edge of it.

PS, they couldn’t figure my ignition issue.
Click to expand...

Well that sucks. I'm really sorry to hear that. Does anyone have any idea about the engine problem?

I agree, that if you were paying the mechanic to repair your aircraft, he needs to cover the damage.

-Marc
 
Norman CYYJ said:
That crack should have already been drill stopped. How many other little hairline cracks are there you can't see. Yes it should be replaced, yes the mechanic should make it right by covering the costs of the replacement and repairs and yes it should be replaced because you are going to see that ugly crack every time you go flying and it it is just going to cause you to get upset again.
Click to expand...

This **** sucks, and yes, I am borderline heartbroken by it. That being said, I am willing to accept a functional, lifelong fix if it's possible to avoid the downtime and anxiety involved with replacing the canopy itself. I get it, the dude f'd up, but I'm stuck between a rock and a hard place and can look past a crack out of eyes view and on the passenger side. I just don't want it to get worse, and can accept it for what it is in its current condition.
 
Plummit said:
Well that sucks. I'm really sorry to hear that. Does anyone have any idea about the engine problem?

I agree, that if you were paying the mechanic to repair your aircraft, he needs to cover the damage.

-Marc
Click to expand...

Hey Marc,

No, nobody has any idea about the engine problem, neither the mechanic nor Savvy. They tested the p-leads, looked at the wiring at the switch, and checked mag timing, and were unable to recreate the issue. One was at 23 the other at 20, when they should have both been at 23. No one believes that was the source of the issue, so they timed it to 23 and recommended I keep flying unless I wanted to throw parts at it.

Covering the damage is kind of tricky, being that covering the damage means giving me an entirely new canopy, which, obviously isn't an off-the-shelf type of thing. I'll ask him if he can create a functional, permanent fix, and see where we can get with that.

Appreciate you man,

Amir
 
****! Its everyone's worst nightmare and really feel for you.

I would certainly stop-drill the primary crack and maybe you might get away with the secondary crack at the top, but either way it would be worth buying some of that perspex cement and trying to save that piece before it breaks off and disappears. You need to bevel the edge of the crack then apply the cement and give it plenty of time to dry. You will be able to sand and polish the cemented surface to the point it is barely visible although to do all this you will certainly need to remove a couple of screws on the canopy skirt.

That damage to the rear skin is pretty easy to fix. I'd release those screws and straighten the skin, then use either a double-sided tape or a bonding sealant to help keep it tight to the perspex.

It's not an impossible task but it will take time and effort.

To prevent it getting pinged a second time, maybe it might be a good idea to put in those nylon guide blocks on the rollover bar?

Good luck
 
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Canopy crack

I had the exact same crack on a 7 that I owned only the piece broke completely out. Lew Gallagher in Greenville, SC fixed it and it was almost invisible. Lew has fixed many RV canopies and I don't think there's been a single incident of a repaired canopy failing. PM me and I can give you his contact. I realize you're on the opposite coast but Lew is very generous in sharing how to do these repairs. Cheer up, things will be better!
 
I'd sure give repair a try before I'd even consider replacing it, even if it's paid for. I could open up a can of worms. Canopies are broadly considered the most difficult job in building an RV.

Be sure whoever stop drills it knows to not used standard drill bits. That part will crack off completely if one does. There are special bits for plexi. Then perhaps a small fairing of aluminum artfully done to cover that up, glued on with Sikoflex.

Do not put duct tape or similar over it - the chemicals in many tape adhesives will craze the plexi. Maybe someone here can recommend a safe tape as a temporary fix until the final fix is done.
 
Many RV's have the canopy crack in the same place because of the flex in the canopy structure. I even cracked mine some years ago!!!!!

Anyway, some of the attitudes I hear being voiced about the mechanic are rather ugly IMO.

This is a known issue/vulnerability on RV's, but everyone is jumping on the bandwagon ready to throw the mechanic under the bus.
Makes me want to find another line of work.
 
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SwimmingDragonfly96 said:
Do you think it's bad enough to get the whole thing replaced?
Click to expand...

Not in my opinion. Take steps to stop the crack from propagating and drill another hole or two with a screw or rivet to reinforce the now un-supported area, if possible. Got get some vynal and make a 2 or 3" targa strip over the end of the canopy. In the end, it looks like a cosmetic upgrade vs an eye sore, as you will no longer see the canopy frame through the acrylic or the crack. There are some acrylic guys out there that can make a repair to that crack that will be unnoticeable from more than 2 feet away also. The optical clarity through the repair is poor, but no issue in this location.

Need to be careful with some opinions out there. Some people put a tiny dent in a part and have to order a new one, as they are prefectionists (the rest of us just put in a bit of filler before paint). If that is you, then yes, you must order another. If you just want a safe and nice looking plane, see above. I also agree with Walt, accidents happen. Sounds like the mechanic said he would make it right, so don't see the need to bash the guy.

Larry
 
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planenutz said:
To prevent it getting pinged a second time, maybe it might be a good idea to put in those nylon guide blocks on the rollover bar?
Click to expand...
I think he said he had guides on order so that's probably happening anyway. Not that the guides are a solution here, the solution is only lowering the canopy by hand, carefully, every time you walk away from it.

It's likely the gas struts are the stock size which are "okay" new but can let the canopy drop if you move the plane around with the canopy open without thinking about it. I've done it twice, and been lucky not to get a crack when the canopy fell.

I've since replaced the older struts with the next size up in holding strength... The canopy is very solidly held in the raised position now. I am still careful not to walk away from it when it's open, but I'm less worried about a wind gust closing it unexpectedly now. Search on here for "gas strut replacement" or something like that and you'll find a thread discussing the sizes. New ones are only $30 or so for a set from Amazon, well worth the piece of mind.
 
Norman CYYJ said:
That crack should have already been drill stopped. How many other little hairline cracks are there you can't see. Yes it should be replaced, yes the mechanic should make it right by covering the costs of the replacement and repairs and yes it should be replaced because you are going to see that ugly crack every time you go flying and it it is just going to cause you to get upset again.
Click to expand...

Hairline cracks in these canopies are insanely rare. Due to their size and pre-stress from forming, even the slightest weakness of any sort results in a very obvious crack of significant length. Just ask anybody the created a crack while drilling a hole. It immediately creates a long crack as soon as you breath on it.

Lets ease off the fear mongering here. The poor OP is already stressed enough from his string of issues with a new plane.
 
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Walt said:
Many RV's have the canopy crack in the same place because of the flex in the canopy structure. I even cracked mine some years ago!!!!!

Anyway, some of the attitudes I hear being voiced about the mechanic are rather ugly IMO.

This is a known issue/vulnerability on RV's, but everyone is jumping on the bandwagon ready to throw the mechanic under the bus.
Makes me want to find another line of work.
Click to expand...

I was thinking the same.... if it's a common issue, design problem, etc..
it stinks for sure...the guy screwed up when he wasn't as careful as he should be...no doubt....
but we all make mistakes...and none of us know about every potential design flaw, etc....

As I've been dwelling on the idea of building an RV, it seems that I've seen a fair lot of mention of cracked canopies. Really seems like a weak-link for RV's. I wonder...what percentage of canopies crack? and if it's a high number, why I have I not read of anyone making a thicker/stronger canopy or a better design?
maybe the answer to the second question points to the first being a relatively low number(?)
 
Getting taken care of

I appreciate the empathetic turn this post took this morning. I went and met with the mechanic and he was very apologetic about the situation. He’s going to properly repair the crack and build either a targa strip or a carbon fiber piece to cover it. He even offered to push it through insurance if I wanted the whole thing rebuilt, but I’m happy with the repair plan. I will be reaching out to those who recommended Lew so he can chat with my mechanic about the best plan of action with this.

Thanks again, I’m feeling very relieved.
 
Walt said:
Many RV's have the canopy crack in the same place because of the flex in the canopy structure. I even cracked mine some years ago!!!!!

Anyway, some of the attitudes I hear being voiced about the mechanic are rather ugly IMO.

This is a known issue/vulnerability on RV's, but everyone is jumping on the bandwagon ready to throw the mechanic under the bus.
Makes me want to find another line of work.
Click to expand...

I agree, Sh!t happens and when it does it's all about how the problem is dealt with. Sounds like in this case the shop is steeping up and doing the right thing with all the info they have been provide. Shout out to shops like this, we need more of them, but it seems they are going away as time passes.
 
Walt said:
Many RV's have the canopy crack in the same place because of the flex in the canopy structure. I even cracked mine some years ago!!!!!

Anyway, some of the attitudes I hear being voiced about the mechanic are rather ugly IMO.

This is a known issue/vulnerability on RV's, but everyone is jumping on the bandwagon ready to throw the mechanic under the bus.
Makes me want to find another line of work.
Click to expand...
While I don't agree with some of the strong language used, I do agree if a damage is caused by the mechanic/shop, they are responsible and have an obligation to make it right and satisfactory.
 
Canopy Cracks

I have a slider. IMO it is less likely to suffer cracks. Still can because I feel the plans 'pop rivet' attachment doesn't provide proper expansion/contraction freedom. About to start a canopy replacement on another a/c (not even flying yet) which suffered a huge crack right on top.

The tip-ups on the other hand... Friend and I working on his 6 tip up, *in his hangar*, gust of wind came by and slammed the tip-up canopy down. New cracks (about the same place as yours) and twisted the whole structure.

Clearly from notes above the struts need to be upgraded.
 
Snowflake said:
I think he said he had guides on order so that's probably happening anyway. Not that the guides are a solution here, the solution is only lowering the canopy by hand, carefully.

It's likely the gas struts are the stock size which are "okay" new but can let the canopy drop if you move the plane around with the canopy open without thinking about it. .
Click to expand...

I agree that the guides are not a total solution but they do help a little. As you say, the struts play a big part in this and it has always surprised me that more people haven't given this subject more thought. Back in the 1990's when gas strust first became a thing, everyone followed one persons idea on how to install them and the geometry is not as good as it cood be with this now "standard" sertup. Once the top of the strut goes over-centre there is no support.

The way we position them down here provides support to the canopy most of the way down. I can open my canopy 3 or 4 inches and it will remain there, fully supported by the struts. The chances of it slamming closed is very small.
 
Pretty much any airplane with a canopy can have issues. I've flown every model of two seat RV and don't find them to be any more fragile in that department than Pitts, Extras, or other airplanes that I've flown.

Speaking of which, ever priced an Extra canopy? You can buy a whole RV for the cost of an EA300 canopy replacement!

--Ron
 
Time for a Targa strip. And welcome to the club....

....cracked mine in the same spot 15 years ago.

You can see the targa strip which covers it HERE. I'll get you a better picture the next time I'm out at the hangar. Can also see it HERE. Pretty easy cover to make, and it strengthened the area considerably. A long list of dings and scrapes.... Proof of use.

And sorry about the crack. I thought about painting my crack-hiding targa strip 15 years ago, but kinda like it now in raw alum.

v/r,dr
 
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Attach the targa strip with Sikaflex. If the crack is stop drilled it shouldn’t travel past the Sika.
 
My vinyl gut made me a targa out of vinyl. Looks great...
 

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Weak Link? Not exactly.

Blw2 said:
I was thinking the same.... if it's a common issue, design problem, etc..
it stinks for sure...the guy screwed up when he wasn't as careful as he should
Click to expand...

This is a warning for all -7x tip up owners. This is a build solvable item, but not noted in the plans (or missed).

There is a hidden area under the little bent skin tab. The roll bar intersects the side rail and attaches with a large piece of angle. The slot where the canopy goes under that skin hides the edge of the angle, the same thickness as the canopy. In the building stage, after reading about broken corners, I noticed this issue one day and cut the canopy up 1/4". Inspect yours - don't allow the canopy to become the hard stop.

Someone one must have been whispering my my ear to do this because less than a week later I stupidly closed the garage door and it hit the open canopy allowing it to slam down, albeit w/o damage. I also have hard rubber stops on the canopy rail that set a fixed gap against the fuse side rail. Canopy closure guides are also needed to prevent the twist from allowing the plexiglass to scrape the roll bar as in the OP photo. Usually when it falls on its own weight it is straight.

Amir, I would get a known, qualified RV person to replace that canopy now. It will break off. IMO the labor to replace is not as high as one might think. Scott McDaniels has described it here before, sorry no link.

Canopy Corner Gap.png
 
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I know this is a bummer for sure but there is a bright side. It's not in a place like in front of your eyes. I would take a conservative approach. Super glue it and stop drill. If seeing it bothers you too much then like the builder suggested, maybe a strip to cover it. Let me add something. I've not suffered a crack like this but over the years, I have noticed a few tiny stress cracks. All I ever did was super glue them and they've never changed.

Regarding what others have mentioned about this being an inherent flaw of RV's... I agree. As much as I love the wide open view in my tip up 7, I wish the canopy wasn't such a single big piece. I would be happy(ier) if it was perhaps a three piece with strips connecting each. I'm sure there are all kinds of internal stresses in the canopy of our RV's. I really worry about cold weather too.
 
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Here's a pic of my repair, been there for quite a while...
Barely noticeable really.

i-7tMppNM-X2.jpg
 
I have read each post in this thread and now introduce a different perspective.

I have not searched the forum or builder's logs at this point.

I picked up on a possible point of interest from the first photo in the first post. The flush screws attaching the canopy to the frame.

The Thorp TT-18 was the first homebuilt to utilize a "large" moveable canopy (comparatively). John Thorp had a lot of experience in canopy installations in his numerous designs. The installation detail for the T-18 also uses flush screws but specifies for holes much larger than the screw heads (from visual memory 7/16"- 1/2") and the canopy is attached using large flush washers.

The reason was the differential in the coefficient of expansion between the metal structure and the canopy plastic. This is compounded by the length of the edges.

I don't have much more to offer because I'm away from my computer archive and only have a sketchy recollection of discussing with John the approach of canopy attachment using Sikaflex alone, which was when he mentioned his concerns regarding the coefficient of expansion.

But I do feel it is worth considering if it hasn't been addressed before.

FWIW
 
Marc Bourget said:
I have read each post in this thread and now introduce a different perspective.

I have not searched the forum or builder's logs at this point.

I picked up on a possible point of interest from the first photo in the first post. The flush screws attaching the canopy to the frame.

The Thorp TT-18 was the first homebuilt to utilize a "large" moveable canopy (comparatively). John Thorp had a lot of experience in canopy installations in his numerous designs. The installation detail for the T-18 also uses flush screws but specifies for holes much larger than the screw heads (from visual memory 7/16"- 1/2") and the canopy is attached using large flush washers.

The reason was the differential in the coefficient of expansion between the metal structure and the canopy plastic. This is compounded by the length of the edges.

I don't have much more to offer because I'm away from my computer archive and only have a sketchy recollection of discussing with John the approach of canopy attachment using Sikaflex alone, which was when he mentioned his concerns regarding the coefficient of expansion.

But I do feel it is worth considering if it hasn't been addressed before.

FWIW
Click to expand...
If you look at my photo above that is exactly what you see, Tinnerman washers which basically float in oversized screw holes. Even the repair double was made the same way, dimpled doubler in OS holes and screws are just snug enough to hold the plexi on without applying any pressure in tension.
 
Marc Bourget said:
I have read each post in this thread and now introduce a different perspective.

I have not searched the forum or builder's logs at this point.

I picked up on a possible point of interest from the first photo in the first post. The flush screws attaching the canopy to the frame.

The Thorp TT-18 was the first homebuilt to utilize a "large" moveable canopy (comparatively). John Thorp had a lot of experience in canopy installations in his numerous designs. The installation detail for the T-18 also uses flush screws but specifies for holes much larger than the screw heads (from visual memory 7/16"- 1/2") and the canopy is attached using large flush washers.

The reason was the differential in the coefficient of expansion between the metal structure and the canopy plastic. This is compounded by the length of the edges.

I don't have much more to offer because I'm away from my computer archive and only have a sketchy recollection of discussing with John the approach of canopy attachment using Sikaflex alone, which was when he mentioned his concerns regarding the coefficient of expansion.

But I do feel it is worth considering if it hasn't been addressed before.

FWIW
Click to expand...

It is not uncommon to upsize the hole slightly*larger than the screw precisely for the reason of different expansion rate which will help for those in a real cold climate.* A 5/32" hole for a #6 screw or 3/16" for #8 screw is often used and won't require a tinnerman washer.
However, this type of crack probably won't be prevented by a larger size hole.
 
Bavafa said:
It is not uncommon to upsize the hole slightly*larger than the screw precisely for the reason of different expansion rate which will help for those in a real cold climate.* A 5/32" hole for a #6 screw or 3/16" for #8 screw is often used and won't require a tinnerman washer.
However, this type of crack probably won't be prevented by a larger size hole.
Click to expand...
The tinnerman is used so the there is no force being applied to the plexi in the CS part of the hole, the force to hold the canopy is strictly on the flat side of the washer outside the CS (washer floats in the hole). The trouble with a CS screw or rivets directly in the plexi is it's going to try to 'split' or expand the hole sort to speak.
 
the T-18 design provides for a spacer (from small alu tubing) between the structure and the tinnerman - "trapping" the plexiglass and permitting some shift during expansion.

Humidity can also increase expansion.
 
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