Glue the wing back onto my C-172?

AuntPeggy

AuntPeggy

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My son gave me a mahogany model C-172. It had an uncontrolled flight into terrain from the top of the computer onto the floor and one wing broke off. Can you suggest a good way to glue it back on so that the repair is invisible?
 

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Use either cyanoacrylate (Super Glue) or hide glue. The latter is used to repair fine wood musical instruments. Also, I think hide glue will make the most invisible glue joint.

Do you have a plan for how to keep the parts in alignment while the glue cures?

EDIT: If you truly want an invisible joint, don't rush the job. It would be helpful to have a picture of where the wing broke and a close up of the break.
 
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Has the NTSB investigated yet? What about a lawsuit against the manufacturer, is that a possibility? :D
 
As richard said, hide glue. CA can remain on the surface and will be shiny and easily seen. hide glue will soak in and can be washed off the outside of the joint when still wet. Adding water to CA will turn it hard and opaque white instantly. So it cannot be washed off.
 
SA is ok, but I'd stick with real wood glue as it gives you better working time and cleanup. The Urethanes aka Gorilla glue are pretty good for wood. Of course if you want to keep it airworthy, you'd be better off with Resorcinol :-)
 
I've successfully made repairs of this type using CA. But it is messy stuff and requires patience and tactile exactitude to the level of a jeweler (if you want a precise and invisible joint). Hide is a strong joint and less exacting. You have to know how much is enough/how much is too much. Practice helps but it should be a project in itself.

Since Elizabeth won't need that much hide glue I suggest she go to a fine furniture restorer. Besides, he'll have the shop ability to hold the pieces exactly for the cure time. Or maybe visit a retired modeler.

I'd charge $10 if anything. Or a 6 pack of Dr Pepper and her looks would suffice.:)
 
AuntPeggy said:
My son gave me a mahogany model C-172. It had an uncontrolled flight into terrain from the top of the computer onto the floor and one wing broke off. Can you suggest a good way to glue it back on so that the repair is invisible?
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Clean break along an existing joint or jagged wood?

The first is easy. Even some plain old ordinary white glue (elmers) or yellow glue (titebond) will probably do if you are careful not to apply too much. Scrape off the old glue first.

Broken wood is much harder to get the bits back together without a visible seam.
 
Why not drill matching holes at one or two places and insert steel pins to give it strength while you're at it.
 
1 tiny drop of Gorilla glue.
 
lancefisher said:
Why not drill matching holes at one or two places and insert steel pins to give it strength while you're at it.
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I use wooden tooth picks with the sharp ends nipped off.

Several problems here:

--the holes need to line up exactly. Across the chord shouldn't be difficult but across the wing thickness it would be difficult without a jig.

--the dowel would have to be a tight fit therefore increasing the requirement for accuracy in alignment. An alternate is to drill several sizes larger than the dowel and fill will epoxy or glue. Now it's becoming a project.

--lacking that precision, the repair would stick out like a sore thumb.
 
Richard said:
I use wooden tooth picks with the sharp ends nipped off.
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I don't think a wood "pin" would add any strength. Steel is much stronger for a given diameter.


Several problems here:

--the holes need to line up exactly. Across the chord shouldn't be difficult but across the wing thickness it would be difficult without a jig.

--the dowel would have to be a tight fit therefore increasing the requirement for accuracy in alignment. An alternate is to drill several sizes larger than the dowel and fill will epoxy or glue. Now it's becoming a project.

--lacking that precision, the repair would stick out like a sore thumb.
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You're alternate is exactly what I had in mind. Make a tight fit in the wing and then drill/ream a loose hole in the fuselage that allows the wing to be arranged correctly. Then fill the large hole nearly full with epoxy. The result would probably be stronger than the original. You could also apply a think coating of glue to the abutting surfaces of the break for added strength and to fill any voids at the surface.
 
biscuit joiner! and a new excuse to buy a new tool!!! :-)
 
lancefisher said:
I don't think a wood "pin" would add any strength. Steel is much stronger for a given diameter.




You're alternate is exactly what I had in mind. Make a tight fit in the wing and then drill/ream a loose hole in the fuselage that allows the wing to be arranged correctly. Then fill the large hole nearly full with epoxy. The result would probably be stronger than the original. You could also apply a think coating of glue to the abutting surfaces of the break for added strength and to fill any voids at the surface.
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The "pin" does add strength but mostly I use it for alignment. I only use this method as needed which is rare.

But here's the catch; we don't know where the break is. I think you're assuming it's at the fuselage. It would be a clean break at that location (easier to fix) but without further info from E, we don't know.

AFA "gap filling" with the glue, I doubt that would be desired due to the expressed desire to have an invisible repair plus the it would contrast to the existing finish. I assume any gaps after the regluing could be filled with clear varnish or even clear nail polish in order to match the finish. Even aliphatic wood glue dries to a matte finish and is slightly opaque...ie, noticeable.
 
gkainz said:
biscuit joiner! and a new excuse to buy a new tool!!! :-)
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Do they make biscuits small enough? Aw, who cares...more tools is goood!!!!

BTW: I've used the tip of tongue depressers for this purpose. We're talking of modeling.
 
When I went to photograph the airplane and its various parts, it was gone, so I suppose Hubby has beat us all to the job. I'm waiting now for the chance to review the work.

BTW, you guys realize its only about a foot tall (with the stand) and less than 1-1/2 foot in length, right?
 
O gee...it was stuck in my head that it was Elizabeth who started this. Sorry, Peg.

So if hubby did tackle the job you shouuld expect receipts for new tools?
 
Well, the C-172 is back flying high over the computers. I don't remember which wing broke off, but it seems adequately repaired. I'm sure there is an AI signoff somewhere around here.
 

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Remember to log the flight time.
 
AuntPeggy said:
Well, the C-172 is back flying high over the computers. I don't remember which wing broke off, but it seems adequately repaired. I'm sure there is an AI signoff somewhere around here.
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I'd hold off on any high-G maneuvers until you get some time on the repair.
 
AuntPeggy said:
Well, the C-172 is back flying high over the computers. I don't remember which wing broke off, but it seems adequately repaired. I'm sure there is an AI signoff somewhere around here.
Click to expand...

TRAFFIC ALERT! Cessna IMMEDIATE DESCEND, RIGHT TURN. Your traffic is an acro biplane climbing on your right!

:D

-Skip
 
There is an STC available for your make and model to keep the wings from falling off. It's an easy process and not too heavy in the pocket book. contact me for further information. Be prepared to provide bank account information.
 
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