Bad Gear Legs

[PA1195]

Airframes has a jig, but I dont think they have done many gear legs. I talked to them in the mid 2000's and one of the guys showed it to me. Lee Budde is who built it and it went when he sold airframes and kept airforms from what I remember. Tim

I bought my lift struts from Lee as he was transferring that STC to Airframes. He had a Taylorcraft so maybe that's why he also had a gear jig made up. If the new Airframes Alaska still has it maybe they can do repairs...or maybe would be willing to sell the jig to someone who's interested?

Gary

[N96337]

Thanks Dave!

[Guest]

Thanks Dave!

Sorry John. I scoured the remote hard drive and found lots of pictures but not the ones I was looking for.

I do recall posting a picture of it but did not find this AM.

Dave

[Jim Herpst]

I have a left gear with a slight bend in the streamline tubing. Previous owner ground looped hence taking the plane down in 1985. I was told could bend it back . it is a slight bend however me thinks no matter if the streamlined tubing piece is to be replaced it should be straightened first to line the gear up.

[Hank Jarrett]

Once any tube has ANY bend in it there is a significant loss of compression strength. A curved (even slightly) tube will fail in long column buckling well before a straight one. Straightened tube is OK, but you need to be VERY sure it is actually straight!

Hank

[Guest]

The streamlined tube in the landing gear is only subjected to tension buckling is not an issue there.<= this statement is wrong and has been corrected below.

Sure straighten it, weld in a temporary brace, cut out the bad, weld in the new.

Take it to somebody that's skilled in the art.

Dave R

[astjp2]

The streamlined tube in the landing gear is only subjected to tension buckling is not an issue there.

Sure straighten it, weld in a temporary brace, cut out the bad, weld in the new.

Take it to somebody that's skilled in the art.

Dave R

Dave that is true up untill the windward gear is side loaded causing that tube to be put into compression which is a quick way to a failure. The Alaska boys weld a support tube from the diagonal up to a main tube to prevent compression failures. Tim

[Guest]

Interesting Tim, good insight, I missed that consideration. Thanks, Dave.

p.s. Actually I should have quickly thought of that, my bad. Because when I was on a field with a long paved runway I liked to raise the left wing on take off and get up on the right wheel, "drive" to the right side of the runway then "drive" back to center and lower the left wheel, raise the right, "drive" to left side and then back to center and repeat until I ran out of runway. Object was to never lat a tire cross the center line and practice being on one wheel. That had to put compressive loads there like you described.

[Guest]

I have a left gear with a slight bend in the streamline tubing. Previous owner ground looped hence taking the plane down in 1985. I was told could bend it back . it is a slight bend however me thinks no matter if the streamlined tubing piece is to be replaced it should be straightened first to line the gear up.

I have straightened some with slight bends merely by applying heat properly that may save you a lot of work.

One day Tim Popp talked about using compressed air to straighten oil tanks. I tried it to take dents out of streamlined tube and it worked there too.

Dave R

[Hank Jarrett]

Straightening WILL work, just make sure it is REALLY STRAIGHT! Don't just eyeball down the tube. Also on parts that tend to fail in compression remember you are changing the local heat treat near where you applied the torch! The spot where enough heat is applied to bring a dent out with air pressure will change the heat treat. That is why the welded ends of the tube are not as strong per square inch as the rest of the tube.

Hank

[Guest]

Gee, after being an A/P mechanic for about 40 years and and IA for over 20 I am glad that I finally learned how straighten and heat. lol

[Hank Jarrett]

Dave, Knew YOU know how to do it, but everyone here isn't as experienced.