Re-Rounding a Tube

[Oraclejacket]

I have a landing gear weldment that was repaired by a local welder. The welding process resulted in a slightly oval tube at one end (the one where a machined gear leg inserts). What's an appropriate method to re-round the tube?

The tube is supposed to be 1.375" ID, and after the repair, it is 1.36ish on the small axis and 1.382ish on big axis. The 1.375" gear leg will not fit...

How about pulling (or pushing) a tapered mandrel through it? 1.375 OD? Or should I make one that is oval (with a long axis of... 1.38?) and press/pull/drive it through to expand the tube on the small axis of the tube to account for spring back?

Thoughts?

[BTromblay]

Hi,

I have repaired out of round tubing by machining a round mandrel to 1.370 diameter and using a planish hammer and hitting the 1.385" sides of the oval tube, if that makes sense. By working around the tube you can make it round again. With that said, it depends on material thickness, grade and heat treatment. I turn a tapered lead on the mandrel which allows me to insert the tool into the pipe.

My concern is the welding of a landing gear component. I'm an A&P IA and I specialize in landing gear manufacturing, repair and overhaul for vintage, antique and warbird aircraft in standard and experimental category. Please send me a PM if I can assist you in this repair.

Bill

[crystallographic]

Hi Kyle,

I have also re-rounded gear leg tubes - not a big deal (unless a Beech 18 ? )
The mandrel can be slightly smaller - .010" - and bumping it in with some grease makes it easy - then bumping the high ridges on O.D. back and forth, with a smooth flat-faced strike tool and ball pein hammer, will not leave marks or stretch the tube wall.
Done a bunch = not a biggie.
Smooth accurate results.

[Blackfinger]

Ive seen ball bearings of the appropriate ID pushed/pulled through the large diameter oil and coolant tube.