Safety Wiring my prop

[Flying Canuck]

I had my Whirlwind 200RV prop away for tear down and reinstalled it this afternoon. Managed to get it on and torqued without too much trouble. I then tried to safety wire the bolts and got the first bolt wired but then I couldn't get the 0.032 wire to feed through the hole in the bolt head. It's the welded nut style bolt head with short tubes connecting to the hole in the bolt shank. I was able to get 0.025 into the hole in the middle, but not the required 0.032.

Are there any proper ways to deal with this? I was thinking of finding a 0.040" drill bit and reaming a path through, is this appropriate? I can't replace the bolts since they are factory inserted.

I'll call Whirlwind tomorrow, but just thought someone here may have encountered this and worked through it (sorry, pun intended I guess).

[schristo@mac.com]

Mark the position when torqued then back it off as needed to get the safety wire through, then tighten back to the mark.

[Taltruda]

Sounds like the roll pins that Hartzell props use, and they specify .032 safety wire though the roll pins. I wouldn’t drill the roll pins for .040.. you’ll probably break the drill bits trying it.

[scsmith]

DO NOT try to drill the holes.

You can back the nut off, feed safety wire through, and then re-torque, or re-tighten to a mark.

Quitely under our breath, I can admit that lots of people believe it or not do not safety-wire their props. But with the technique described above, it is not too hard, and personally I can't image not doing it.

[Taltruda]

Another trick for feeding the safety wire is to make a loop of wire and use it like a snare tool and place the loop under the roll pin. Then you feed a straight piece though the bolt, and pressing the straight piece, you pull the snare and it brings the wire with it.

[erich weaver]

Love my WW prop, but boy do I hate safety wiring the prop bolts.

I asked WW if I could use Nordlock washers as an alternative but they do not recommend it for the 200RV prop. Not sure what the reasoning was.

[Flying Canuck]

Thanks for the quick feedback, drilling seemed too brute force to me, glad to see that there's a way to do it right. I too can't imagine not safety wiring the prop. It's a shame that it's difficult, but it's got a very important job.

[rv8ch]

Originally Posted by erich weaver

Love my WW prop, but boy do I hate safety wiring the prop bolts.

I asked WW if I could use Nordlock washers as an alternative but they do not recommend it for the 200RV prop. Not sure what the reasoning was.

I think one of the advantages of Nord-Lock washers and one of the disadvantages of safety wire is that it's very easy to check to make sure a bolt is still torqued properly with the Nord-Lock.

I've seen bolts that have not moved, but became loose over time due to compression of the materials. But what a hassle to remove safety wire just to find out all the nuts/bolts are still tight!

My plan is to switch to Nord-Lock wherever not disapproved, so I took out a second mortgage on my house and bought an assortment of sizes from ACS.

[maxmirot]

Nord-lock with Torque seal should cover inspection concerns.

[Walt]

Originally Posted by scsmith

Quitely under our breath, I can admit that lots of people believe it or not do not safety-wire their props. But with the technique described above, it is not too hard, and personally I can't image not doing it.

Put me in that “believe it or not” camp, waste of time IMO. Put a torque wrench on them at CI if you’re worried about it.
I’ve seen sheared bolts that would visually appear fine, until you put a wrench on them.