Main Blade Damage Tolerance

[Si Goodchild]

Gents,

Need your advice again. On practicing how not to crash when the engine quits (autos), I crashed. Bugger.

It was a pretty lame crash, more of a heavy landing with the usual shafts damaged. Unfortunately the BBT Maniac 603s took a hit in that one of them struck the boom and took a dent in the leading edge. I haven't got a photo for you yet but wondered whether there is any scope for a repair as one blade is untouched and the damaged item has struck the 3mm socket cap head fastener on the boom clamp and taken a very circular impact straight on the leading edge. The impact point is about 4 inches from the blade tip so in my mind that area's a lot less stressed than the root. Also, I'm thinking that the blades have a fair bit of strength throughout their structure and are not solely reliant on the leading edge.

What are your thought regarding a repair? Could I pack with epoxy and re-balance if necessary? I do have some access to a carbon fibre repair shop at work so could use their super-runny epoxy, apply some carbon strands and even vac-bag it whilst applying heat. That said, I'd sooner do an epoxy job in the garage at home unless you guys tell me I'm mad to take the risk for the sake of a new set of blades at £50.

I'm not doing any mad 3d, just sport flying. What's the consensus of this forum?

Si

[Andy from Sandy]

Near the tips of most blades is a lead weight. You may have damage to the blade that you cannot see.

Does the blade make any noises if you twist it?

Small nicks in the trailing edge I would think you can get away with.

Damage to the leading edge I wouldn't take a chance with.

[J-S-Q]

Personally I wouldn't take the chance on a 600 size heli -maybe on a 450 but not on something bigger. I'm sure some will say repair it but you will be taking a risk. Remember that if you buy a new set of the same blades you will still have one spare blade in case you have a similar incident in the future.

[GravityKills]

Usually I'm not with the fun police when it comes to blade damage. But in this case I'd be careful because of the lead weight, as was already mentioned.
One batch of Align CF blades reportedly had a similar problem even when they were new.

[Paulice]

Personally I wouldn't take the chance on a 600 size heli .

I agree ^ using any damaged blades is dangerous.

[Mikee]

I had a damaged blade delminate in mid air.. looked a pigeon that had been shot with a rifle.... straight down... don't chance it

Mike

[Downdraft]

Mmmmmm,
Me thinks £1000 heli versus a pair of £60 blades. It's a no brainer sling it in the bin and keep the good one for a spare, if it were to fail in mid flight chances are it's gonna cost you more than a pair of blades and a couple of spindles!

[SRH990]

I'm agreeing with everyone else, minor trailing edge damage, I'd consider it, leading edge damage it goes in the bin, a lot of the strength of the blade is in the leading edge area.

[Si Goodchild]

okay guys, thanks for the reality check.

[waveydavey]

Are the blades we buy balanced as a pair or as I suspect made as lefts and rights and then packed together. If this is the case we should surely between us have numerous pairs of blades if all of our singles were to come together. What do you reckon?

[Janek]

I think you made to correct choice.

But one point regarding Align blades, yes, they did have a problem with shedding their lead weights in flight, BUT, and its a big BUTT (sorry not talking about mine ! ), but.

I saw the results of a "funky chicken" on a set of new 700 Align blades, and the NEW design is to encase the leading edge lead weight in Epoxy, which is obviously super strength as the remnants of this crash was just the epoxy and the lead, the rest of the blade has disappeared (except for the very tip (about 2 inches). I'm not easily impressed, but when I saw that on the bench, I would definitely now recommend Align blades for safety.

[SRH990]

Are the blades we buy balanced as a pair or as I suspect made as lefts and rights and then packed together. If this is the case we should surely between us have numerous pairs of blades if all of our singles were to come together. What do you reckon?

Pretty sure they are matched for weight then balanced. A guy at our club has matched orphan blades a few times although balancing can become a chore if they aren't well matched to start with.