The factory did a great job

[Tom G]

I've posted some other threads about my current 5 month annual but have to give credit where it is due. After my mechanic found corrosion in one of my landing gear tie struts I frankly didn't know what to do. I called Taylorcraft and spoke to Harry. He told me that if I sent the gear to him he would put it in the original jig and replace the tie struts, inspect the rest of it and install new bushings. I sent it to him and thats what he did. He did all of that along with recovering the gear and sent it back to me in silver. When the cover was removed they found some additional corrosion in the main structure and repaired that as well. I got the gear back and my mechanic painted them and installed them. They look terriffic.

I was getting a little nervous because the 337s were promised to me weeks ago. I left several messages and didn't get a call back. I then picked up the phone and called and spoke to Harry last Thursday. He promised me he would mail the form to me right away. It arrived today. Sure, I would have liked them sooner but with everything that is going on down there I can understand he may have had bigger fish to fry. Anyway, the fact is that he delivered what he promised to me. In addition they did all the work for a total of $550. I think thats a bargain.

[hangarb7]

Re: The factory did a great job

Good report.

So what tipped your mechanic off on the corrosion? N44057 is Daytona White and I do see some rust spots thru the paint on the gear. It bothers me so I am curious about your mechanic's process for determining that it was just not surface rust, but that it is rusted badly enough to come from the inside out.

I suspect that any 1946 airplane with tubing is going to have this issue at some point, even though my airplane is relatively young hour-wise (1700 TT)

Also did you airplane sit outside for a long part of its life.

Anyone weighing in on this would be great. How many others have had gear replaced or repaired at this point?

Jack Dernorsek
BC12D

[48fordnut]

Re: The factory did a great job

Rust in unprotected tubing is common. I opened a box that had New tubing for a clipwing. outside looked good with zinc chromate. when I stood the strut material up, whoop de do, the scaley rust dumped on the floor. this was in a mailing tube in a un heated area. its just head light stand material for a hot rod now. . dosen't matter how many hrs on the plane, its still 60-65 yrs old.

[hangarb7]

Re: The factory did a great job

Fordnut,

I certainly understand that hours on an airplane mean nothing as far as rust is concerned. What I meant was that my airplane has sat a lot of the time, with many months, even years of inactivity. Luckily, I believe most of that has been under cover, although always in unheated spaces; and the previous owner of twelve years had a dirt floor hangar. I was trying to give a better picture of my airplane.

The question remains, what are the signs that his mechanic saw that prompted a rejection of the gear as acceptible?

Tubing that is sitting idle in a box is relatively easy to inspect (and dump out the scaley rust, as it were). How do you pass judgement on a landing gear assembly that is unopened? That's my question and one that I think I may need to instruct my mechanic on. Too many mechanics are unfamiliar with rag n tube structures, and I want to alert him to the possible effects, but not alarm him enough to just reject it if some small rust is apparent.

As an intimate owner of a lovely old gal, I know for a fact that I am inspecting my airplane better than my mechanic, but I'm not complaining.

Jack D.

[Robert Lees]

Re: The factory did a great job

If you were to be sufficiently concerned, you could get the important areas inspected using ultrasound.

We did this for our lift struts & gear during our rebuild, and a few suspect areas were found, that we had repaired.

NDT is non-invasive and comes in a variety of forms...ultrasound, X-Ray, CAT etc. We found a suitable outfit at the local major airport who do this work for the airlines.

Rob

[hangarb7]

Re: The factory did a great job

Thanks, Robert. Does the questionable part need to be removed for testing?

Jack

[Tom G]

Re: The factory did a great job

ok guys, what my mechanic saw was a crack about 3 inches long on the trailing edge of the tie strut on the right gear. The crack ran along the trailing edge. The rest of it looked ok but this was a signal that there was trouble inside. I didn't know what to do! I decided to call Taylorcraft and after talking to Harry he offered to rebuild them for me. I wasn't about to have one gear rebuilt so I sent both down. The crack was on the trailing edge so of course you could only see it from the rear. If you looked at the front of the gear everything looked fine. I'm sure this didn't just start and was probably there at the last annual as well. This is a new mechanic I'm using who is very familiar with the tube and fabric 40's taildraggers and that is really all he wants to work on. I'm VERY glad that I went to him. He's got my business from here on out. He also made me replace the exhaust which was needed and is he ever a fanatic on paperwork. By the time this annual is done this will be the best documented T-Craft on the planet!

Hopefully next year's annual will be a fly thru!!

[Forrest Barber]

Re: The factory did a great job

The tie strut SB addresses this issue, with the proper hole drilled and anti-corrosion stuff shot into the hole and keeping it cleared out will solve the problem before it starts. However if moisture builds up inside the tie strut and it freezes , then this cracking can occur. Usually the strut is rounded outa bit too. THAT is the reason for the bolt at the end of the tie strut. Easy repair with a replacement tie strut welded into place.

[Robert Lees]

Re: The factory did a great job

Does the questionable part need to be removed for testing?

No it doesn't for Ultrasound, but probably does for X-Ray and certainly for CAT Scan, ask your NDT'er for their opinion.

Rob

[Tom G]

Re: The factory did a great job

Forrest is right, apparently mine were never drilled. I highly recommend that all of you check for this and comply with the service bulletin if it hasn't already been done.

[Robert Lees]

Re: The factory did a great job

When I examined my gear tie-struts during my rebuild project, I noticed that the welds at each end sealed the tubes, so I was confused as to why the hole would be required in the first place? I noticed what appears to be a jigging hole, and on mine this is sealed.

I had the whole gear ultrasonically tested for internal corrosion, and none was found on the tie-strut.

Both gear legs already had the additional drilled hole anyway, so I used tubeseal to seal the internal surfaces.

Rob

[barnstmr]

Re: The factory did a great job

How can I get my hands on a copy of the SB?

[Robert Lees]

Re: The factory did a great job

The essence of it is here:

Service Bulletin 78-001 - The landing gear tie-strut can be a problem area for rust especially if Service Bulletin 78-001 hasn't been done. This involves drilling a drain hole (#40 drill bit) on the trailing edge of the streamlined tube about a 1/4" up from the bottom. If water comes out you have a problem, if not you should inject oil (Tubeseal) . If the lower part of the tie-strut is badly rusted it could let go on a hard landing and up would come the gear taking out the strut, prop, front wing spar causing a major hit on your wallet. This area can be reinforced by welding on a strap. Contact the Foundation if you need a complete copy of this Taylorcraft Service Bulletin.


(from the Foundation website)

[Guest]

Re: The factory did a great job

When I examined my gear tie-struts during my rebuild project, I noticed that the welds at each end sealed the tubes, so I was confused as to why the hole would be required in the first place? I noticed what appears to be a jigging hole, and on mine this is sealed.

I had the whole gear ultrasonically tested for internal corrosion, and none was found on the tie-strut.

Both gear legs already had the additional drilled hole anyway, so I used tubeseal to seal the internal surfaces.

Rob

Rob,

On mine that "jigging hole" goes thru to the inside of the tube and appears to function as a vent.

I have been cleaning it with a piece of safety wire for 25 years to keep it open.

I always thought it was a vent and it appears to be at the low spot.

Dave.

[Robert Lees]

Re: The factory did a great job

Makes you wonder why it goes through, though...if it were to be sealed, no water/condensation could get in, ergo no internal corrosion.

Oh well, 'twas not to be.