Possible to fix prop blade from screw hit in flight?

DavePA11

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Hi,

Took a flight in a Magni M24, and when putting it back in the hanger noticed one of the screws for the side panel was missing.

Different gyro, but can see where the screw is located with the yellow.

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Didn't find any issues with the leading edge of the prop, but after more inspection it potentially hit the prop.

Can the prop be fixed somehow or must the blade be replaced? Can it just be sanded down to a smooth surface?


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Does Magni use or recommend use of Loctite on these screws?
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Last edited:
Dave, That looks cosmetic, can you compress it with your thumb? Is the prop hollow carbon with a Rohacel core?
I would find out what the paint is (If there is any) and if it doesn't have noticeable compressive damage, Scotchbrite it, touch up the paint
and color sand it like you would on a car repair.
I would check with Magni to see what they used on the surface and the blade construction before doing anything.
If the core is damaged, it can still be fixed.
 
If It is deep enough to require a patch. Take the propeller off and lay it so the section requiring a patch is flat.

Fill the area with baking soda. Get some liquid super glue. Not the gel type. Get the baking soda wet with the super glue. Add more baking soda and apply more super glue if needed.

After its dry. File it flat to conform go the curvature of the blade. It files and sands like wood. Paint and you're ready to go.

Note! When you apply the super glue it ill give off fumes. Do not breath the fumes. Very bad for you.
 
If It is deep enough to require a patch. Take the propeller off and lay it so the section requiring a patch is flat.

Fill the area with baking soda. Get some liquid super glue. Not the gel type. Get the baking soda wet with the super glue. Add more baking soda and apply more super glue if needed.

After its dry. File it flat to conform go the curvature of the blade. It files and sands like wood. Paint and you're ready to go.

Note! When you apply the super glue it ill give off fumes. Do not breath the fumes. Very bad for you.
I've repaired my prop this way. I heard that they also used this method on Huey helicopter rotors.
 
That method is good for filling nicks, but if there is any delamination, or spongy substrate, you should really only use a suitable epoxy such as RL Systems.
Especially if it is epoxy carbon to begin with. The epoxies will have un-reacted amines that interfere with CA glue adhesion.
It all depends on how critical the repair is. If tossing the patch won't effect the aircraft, then CA is fine.
I used RL epoxy, cabosil and chopped carbon fibers to repair the big dings in the prop on my air command the PO had used crap 5 min epoxy, or CA and I flicked those out with a knife blade.
If the ding goes into the core, the loose skin should be cut away, the edges scarfed/tapered at least 5 to 1, the divot filled with epoxy and micro balloons, and new carbon fiber cloth should be laid on the repair. It can be held firm with packing tape, then shaved flush after curing with a
Polish Mill/Aluminum file.
If it is a very small localized delam., you can get away with injecting epoxy/micro balloon mix under the skin and cover with tape until cured..
 
Thanks for all the feedback. The owner decided to buy a new blade. Maybe he can work on fixing this one as a spare. It’s carbon construction. I’ll have to get the model of it.
 
I have an even worse dent in the metallic leading edge of my Flash 2 Duc Prop Blade. Is it a reasonable option to purchase a single blade? Are they all so uniform as to be interchangable?
 
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