Pre-war welded aileron hinge fittings

[Hank Jarrett]

The hinge fitting thread was mixed in with the 41 deluxe wheel center thread and I will try and put the info on the hinges here. The Deluxe Banjo wheel thread is at ( http://vb.taylorcraft.org/showthread...1-Deluxe-yokes )


As it stands now the following people want welded hinges if we make them. No commitment yet since we don't have a solid price yet, but if you are interested in welded fittings instead of the cast Mag ones (a loose collection of cracks tied together by corrosion and hope) and you aren't on the list, comment here. Let me know any mistakes here.

Hank

People already interested in welded hinges (set would include 4 hinges and two (R & L) bellcrank fittings (no crank, the one from the cast will fit).

Hank Jarrett 2 sets
Jim Hanson 1 set
Tim Popp 1 set
Niri Tawä 1 set
Bernard Dunn 2 welded sets and 2 sets just tack welded
Jake Ring 1 set

[N96337]

Re: Pre-war welded aileron hinge fittings

I'm interested, Hank. Full set for each wing.
John Hanson

[Helicopter D]

Re: Pre-war welded aileron hinge fittings

I would take a set of (4) hinges if possible I have the welded bellcranks in the center but still have magnesium hinges.
Dustin Blevens

[perryv1]

Re: Pre-war welded aileron hinge fittings

Count me in,
a set for each wing please
PV

[Bird]

Re: Pre-war welded aileron hinge fittings

Just want to make sure on this, my plane is prewar and I don't see any magnesium fitting on it including the bell crank, am I correct on this?

[NC36061]

Re: Pre-war welded aileron hinge fittings

Bird,

Magnesium fittings were a post-war development to simplify production and reduce manufacturing expenses. They are interchangeable with welded fittings, after 70+ years there are pre-war wings with magnesium fittings and post-war wings with welded fittings. If you have welded fittings, that's good, the magnesium fittings are garbage. It's a wonder there was never an AD on them to be replaced with the original welded type.

Dave

[Robert Lees]

Re: Pre-war welded aileron hinge fittings

... It's a wonder there was never an AD on them to be replaced with the original welded type.Dave

I guess because there was never a catastrophic failure that brought about an AD. Looking forward, a sensible TC holder would offer new steel ones as a suitable replacement at next re-cover. The TC holder would make money; sensible owners would buy them; the aircraft would be safer, no AD required.

It's good that sensible owners are offering a sensible route for replacement.

Am I missing something?

Rob

[Guest]

Re: Pre-war welded aileron hinge fittings

I don't think you are missing anything Rob.

I suspect though that the cracked ones are a result of a crash or an airplane blowing over and were not found during post incident inspection.

The corroded ones are due IMHO to running fabric right up to the hinge and fastening it there and creating a place to hold moisture rather than cutting the fabric back to match the hole in the aluminum and proving ventilation. Kind of like that strut fitting scenario that rusted out the attach fitting.

Even the steel ones will rust thru if there is not ventilation but they probably will not crack.

Having good replacements is a plus for sure and all the things I mentioned will require replacements.

Dave

[Robert Lees]

Re: Pre-war welded aileron hinge fittings

I got new (NOS) magnesium ones from Harry Ingram. My original magnesium ones were corroded where the steel end fittings attached and also where the aileron cove attaches (the hole towards the right of the photo).



Rob

[N96337]

Re: Pre-war welded aileron hinge fittings

My magnesium ones were corroded almost completely through where the cove attaches. I think the air flow is part of it Dave, but I think a big part is a well meaning owner or mechanic at some point putting a stainless screw through there for the attaches...at least that's what mine had. Between the magnesium, aluminum, and stainless, all you need is a drop of water and you've got a great battery! Goodbye fitting!!
John

[PA1195]

Re: Pre-war welded aileron hinge fittings

How about installing non-critical sacrificial zinc hardware if corrosion is a problem with these brackets? Magnesium is more active but maybe it would help.

Gary

[Hank Jarrett]

Re: Pre-war welded aileron hinge fittings

I am pretty sure even Zinc is more noble than Magnesium. Mag is a great material for sacrificial anodes if you don't mind replacing the anode fairly often. I never could understand why we use it so much. Yes it is very strong and light......for as long as it lasts, but even aluminum (a bit thicker) will produce a part that is just as strong and only a little heavier.

Hank


I guess it is worth repeating here (as was said on the Banjo wheel thread) that anyone who gets these fittings will have to go through the owner produced parts process. The hinges can be made tack welded together and you get to finish weld them and drill the holes up to full size, or you will have to make the manufacture drawing (info will be provided), but you CAN'T just trace an old drawing someone else did, you need to show that you drew (designed in their terms) the part. I have talked to FAA guys who said if you understand the part enough to do the drawing and show it is "equivalent", you can say you designed it, or lastly you can do the quality check of the part (which I can put the info together for).
You actually only have to do one, but I like to do all three and have never been challenged.

[Guest]

Re: Pre-war welded aileron hinge fittings

Interesting examples corrosion Rob and John.

Mine were corroded due to fabric covering trapping water.

I wrongly assumed this was the main reason for it on all planes.

Thanks, Dave.

[Guest]

Re: Pre-war welded aileron hinge fittings

Hinge builders,

I know this will sound stupid but...

Be sure to install the bronze bushing after welding is complete, not before.

I repair many Aeronca landing gear case frames that are cracked because someone welded on it with the bushing in and the bronze got into the weld.

As recently as this week I have had discussions with those that were entertaining welding with a bushing in.

Dave

[Hank Jarrett]

Re: Pre-war welded aileron hinge fittings

Good advice. Considering that even with a good fixture critical alignments can be lost. Always better to drill and final ream the steel AFTER all welding and stress relief.

Ha