Ken Bryant

My Feedback: (10)

Yesterday I shortened my 23X8 Mejzlik prop on one tip. I have cleaned it up and took an equal amount off the opposite side. The prop now balances fine. I am going to coat the tips with some 30min epoxy to seal it and then rebalance.

Should this be a good repair on this or should I just give up?

FWIW, it's now a 22X8

spinner11

My Feedback: (37)

I would go with it. If your on a budget like me these props cost a fortune. Not to state the obvious, but just make sure there are no cracks in it. If it balances fine and the blades are equal length than let er rip!

Nogyro

My Feedback: (10)

If you shortened a Mejzlik prop with a prop strike, you might want to check your crank for run out. Those are tough props!

Aerohead

My Feedback: (37)

The carbon fiber props may be very expensive, but I don't think I'd risk my entire investment (and possible injury) on a repaired one. If you decide to do it, please make sure there are no bystanders to the side or in front of the prop. If it shatters at speed it could make a real mess.

Mike3579

My Feedback: (56)

I would NOT use this prop there could be damage to the prop that you cannot see from the impact!! You could be putting yourself and others at risk.

Tired Old Man

My Feedback: (1)

First, I agree that a damaged C/F prop should not be repaired, but it HAS been done. Not just by us ametuers, but by people that work professionally with composites in scientific locations.

C/F loves ca type adhesives, using some thin to bind the fibers together at the tips works, and some of the "rubberized" ca will seal the tips quite well.

I would have concerns about stress fractures that may be invisible to the eye elsewhere in the prop, tho.

famousdave

My Feedback: (61)

Unless you are sure you have no interlayer cracks or delaminations don't re-use it. The only way to really tell is with ultrasound or x-ray. I saw a video of a repaired CF prop explode in flight, the entire plane was a pile of rubble before it even hit the ground. There are all kinds of hidden damage a CF prop takes when hit.. its not as forgiving like wood.

Also - as someone else mentioned, check your crank for runout or twist, it is quite possible you have both if you hit. Runout will create vibration and could lead to catastrophic crank failure.


I don't want to scare you, but it does not take much to visualize what could happen if a prop or crank let go while you were running it up WOT on the ground...

DP

Ken Bryant

My Feedback: (10)

I don't think I did any damage to my engine. I had just tipped the prop on one end. The engine was still running till I got it to the pits and shut her down, that's when I noticed the prop damage. As for the Prop, I do have access to an NDI lab, I think I might have them ultrasound it to see if there is anything else I need to look at. They owe me a favor anyway

I really think things are fine, I took the 1/2" off both ends to make sure there were no damaged pieces remaining and it balanced fine. I'f anything I might just use it for a backup prop.

famousdave

My Feedback: (61)

if you can ultrasound it, that's the ticket. If the engine was still running, you're right - your engine is probably fine. I have tipped a prop before too and no harm was done, other than to my wallet for the new prop. I tried repairing it, but it got way too noisy for me.


DP