Nasty nipples

[CaptainJon]

It's been a struggle to get the tailwire nipples (A986) and inserts (A4002) apart on Terri's project. Soaking in WD40 for a day, then several hours in lacquor thinner and finally, with much effort, one pair was separated only to find the nipples looked nasty with rust. This plane must have been sitting outside in the coastal Maryland conditions for years, if not decades.......Light surface rust is one thing, but this is to the point that the shoulder on the nipple is diminished severely. So, I shuffle through my spare parts bins and come up with a suitable replacement for the first couple of the sets. Then I check out the parts catalog and see the note "when replacing nipples, inserts must be replaced due to the different size (from original)......"

I have yet to see any different size nipples, or inserts. So when were they changed? That parts catalog note is in both the Alliance catalog and the Lock Haven one. Anyone know what's happening here?

Speaking of inserts, when did the factory go to the "full barrel" style inserts as Terri came with? was this a Conway, PA thing or did Dorothy continue with that style when the F19 came out?



Anybody know if Wag Aero's set of wires, straps, inserts, and nipples is all stainless or just SS wires?

Note the 8-36 threads on the wires and nipples......... trying a 32 tpi die to cleanup a burr on one wire did not work well. Shop trick......... cut an 8-36 nut to the center with a hacksaw and use it as a mini die for a one time cleanup of a bad thread. Works a treat!


Poor man's tap and die set.............


Cheers,

I

[Hank Jarrett]

I have made many a farmers tap and die over the years. They DO work great! I notice you also know how to store them! ;-)

For getting parts apart try KROIL Oil. EXPENSIVE, but works great. Also for rusted parts Oil of Wintergreen works well and makes for really nice smelling parts.

Hank

[Scott]

The originals are rolled threads, the aftermarket stainless versions are cut threads and the two are not interchangeable.

I believe there is a company in the UK that can supply the original thread and there is a post about it on here somewhere.

[Hank Jarrett]

I think Scott is right, but I was told i didn't know what I was talking about years ago when this discussion came up. When I looked at my old tail wires they ALL looked like rolled threads to me. It is all that I will use, but I gave up trying to convince those who were making their own from cut thread stock. You DO NOT want to chase rolled threads with a die! It creates stress risers in the base of the threads that start cracks.
Those who "know better" will do as they please, but I won't use cut threads in place of rolled. Kind of like rib stitching stamped ribs. The discussions seem to always turn into arguments. If your mind is already made up, just scroll on.

Hank

[astjp2]

Yep, the ones from Scotland are about $200 each, Burls aircraft can supply stainless ones if you send him the nipples and the lengths you want.

[CaptainJon]

the two are not interchangeable.

OK, I haven't been through this discussion............ how are they incompatable? My new stainless wires from Wag Aero do fit the old nipples beautifully after cleaning them up with the 8-36 tap............ Are Wag's nipples made differently? I get the cut (V shaped bottoms of the threads) vs rolled (U shaped bottoms) thread thing on the wires, but is there a difference in the tap operation too necessitating a special tap to make the nipples match the rolled threads??

Cheers,

[CaptainJon]

And does anybody else have those "full barrel" inserts on their ship?

[Hank Jarrett]

DO NOT RUN TAPS OR DIES ON ROLLED THREADS!!!!!!!!! When you "clean up" a rolled thread by cutting them with a tap or die you are cutting the metal grain and setting up for cracks! I don't want to get into this whole argument again with people who think they know better but someone is going to get KILLED when one of the tail wires breaks. DO NOT USE TAPS AND DIES ON ROLLED THREADS!!!!!

I am NOT going to get into an argument again on this but if you run a tap into a nipple or a die on the wires you are SUICIDAL! DO NOT DO IT!!! And i don't care HOW many years you have been flying with wires you did it to!

Hank

[3Dreaming]

Hank, with the nipples being an internal thread, are they cut or rolled?

[astjp2]

DO NOT RUN TAPS OR DIES ON ROLLED THREADS!!!!!!!!! When you "clean up" a rolled thread by cutting them with a tap or die you are cutting the metal grain and setting up for cracks! I don't want to get into this whole argument again with people who think they know better but someone is going to get KILLED when one of the tail wires breaks. DO NOT USE TAPS AND DIES ON ROLLED THREADS!!!!!

I am NOT going to get into an argument again on this but if you run a tap into a nipple or a die on the wires you are SUICIDAL! DO NOT DO IT!!! And i don't care HOW many years you have been flying with wires you did it to!

Hank

Hank, someone needs to tell piper that then

[Robert Lees]

Hank, with the nipples being an internal thread, are they cut or rolled?

The internal are cut. You can't roll an internal thread (to my knowledge!).

Bruntons (Scotland) are the company who took over streamline wires from Macwhyte wire company; every streamlined wire in the world comes from Bruntons now. Maybe round wires come from others, but I doubt it.

[Hank Jarrett]

I think you are right about that part. I don't know of any way to roll internal threads. There ARE internal thread taps to fit rolled threads.

[Woody]

It's pretty easy to tell if the wires have cut or rolled threads. Rolling extrudes the metal and the threads are larger in diameter than the base wire.

[Scott]

OK, I haven't been through this discussion............ how are they incompatable? My new stainless wires from Wag Aero do fit the old nipples beautifully after cleaning them up with the 8-36 tap............ Are Wag's nipples made differently? I get the cut (V shaped bottoms of the threads) vs rolled (U shaped bottoms) thread thing on the wires, but is there a difference in the tap operation too necessitating a special tap to make the nipples match the rolled threads??

Cheers,

I bought a set of stainless nipples from aircraft spruce. My original wires were fine, but nipples were suffering from surface corrosion.

I actually had the tail feathers in place for final assembly but the stainless nipples jambed a couple of turns in on the stock wires. I did a quick media blast of the original nipples and installed them without problem.

This year I dismantled the wires to try again. Threads are simply not compatible. I ended up cleaning up the original nipples again and electroless nickle plated them. Happy with the result.

Ps if anyone needs a set of stainless nipples.....

[Guest]

Perhaps the threads on the wire and the threads on the nipples were different classes?

I have seen where mixing classes does not work out well.