Has anyone ever replaced a main gear leg on a 182A that was sagging? I noticed when I bought my plane this year that the left wingtip sat about 4-5 inches closer to the ground than the right side. When viewing the plane head-on sitting on a flat surface it appears that the left main does not have quite the “crown” that the right side has. I’ve examined the fuselage closely for deformation and looked inside the gearbox for anything that might look damaged or deformed. All looks fine. I found a pair of gear legs the other day on a ‘58 in a salvage yard that looked good for a very reasonable price. I’m gonna buy them both. I was told to buy both as they were made in pairs. I have no idea if that's true. Anyway, I want to get them home and strip and paint them. I read not to use a power sander on them as the heat build-up can harm the shot-peering and consequently the temper in them. With regard to striping them, not to use a highly acid stripper as that can harm the temper also. Geez, is there anything that won’t “hurt” an airplane. I was planning on repainting my original gear anyway.

So, any ideas on a gear swap? The guy with the gear says they are no big deal to pull out and replace. He said he has a way to lift the airplane for that but I’m gonna do some research first.

And the stripping? For paint I was planning on just using SEM self etching primer and the white paint I had made up to touch up the plane. It’s a 3-part system with a reducer (for spraying I think) and some sort of catalyst.

Any ideas with experience attached are much appreciated!

niente qui

Be careful if you chemically strip those gear legs, some strippers can cause hydrogen embrittlement. Also not recommended to sand the surface of the gear legs. Those legs were originally shot peened and that process gave a certain hardness to the surface.

Did you give any thought to having your legs overhauled? Might be cheaper and perhaps give you a better piece of mind than salvage legs.

Epoxy primer and polyurethane topcoat best for steel parts on airplanes IMHO.

Sam

I’ve been researching this myself. Here’s what I understand, but please verify:

Any paint stripper that is acidic can allow hydrogen to permeate the steel and cause embrittlement. Cessna says use no chemical stripper to be safe, but I believe anything alkaline will be OK. Turco come is one acid variety and at least three alkaline varieties.

Power sanding isn’t alllowed by Cessna due to the fear of heat buildup that could affect temper. YGTBSM! Yes, hold a belt sander in one spot for a long time with lots of pressure, and it could be a problem. Keep it moving, or use an orbital, and you‘ll be fine.

Sandblasting will leave pock marks with sharp dents. Those jagged peaks and valleys are all individual stress risers and won’t resist fatigue. Don’t do it.

My gear legs have some rust, and layers of poor paint. I consider them to have considerable life left and overhaul would be premature. They’ve spent most of their life in the shed while the airplane has been on floats. Likely most of the paint damage is R & R and storage damage! I’ve ordered some crushed walnut shells and will try to strip and clean them with that.

+ 1 on the recommendation to add shims. Height difference tip to tip/wingspan = height difference wheel to wheel/ track width = total shim height difference one main gear bolt to the other gear bolt/ total of two legs wedge to main bolt length.

Eg: 3” over 36’ span = 13/16” over 10’ track width = .083” over 12” (1’) of length. 6” from wedge to bolt plus another 6” bolt to wedge on other gear. This gives you a starting point how much shim to place between the gear leg and gear box on the low side.

Thanks Pinecone for the response. All good words. Yes, I think my orbital sander should be no problem. The shim issue is something else. I get how that works and I can a shim in my parts manual drawing, and read where to put it in my service manual. However, shim or no shim, it doesn’t change the fact that the left main is actually “flatter” than the right. That’s why I posted the pic. It looks pretty obvious to me but may not to everyone. Or...maybe I’m just losing my mind...

The one gear leg does look a little flat compared to the other.
Take a straight edge on the bottom of the legs and measure the distances at 1" intervals (lofting) and see how different they are from each other.

Jim Hayton is the person you want to talk to about fixing gear legs.
(360) 661-3302
His prices are very reasonable.

check the modifications link to Cessna 180 taildragger conversion. you probably could get a good deal on two new gear legs in great shape

Whatever you do, do NOT use an orbital sander on gear legs. Big no-no... This will destroy the shot peen, which will cause catastrophic failure eventually. Yes, also stay away from most strippers as hydrogen embrittlement will also cause catastrophic failures. You can mechanically strip the paint with a wire wheel on a grinder working longitudinally... but the best thing to do is to send them off to Jim at North Sound Aviation. Jim is one of the last ones on the planet who really knows what to do with spring steel gear. I have sent two sets to him this past month and his work is very good. They will come back properly inspected, reset to factory specs, re peened, re heat treated, and painted with a zinc chromate epoxy primer. Oh... and they will come with the proper paperwork. He is a great dude.

With respect to shims... yes, you "can" shim the gear, but if the lean is so bad that you notice it, the gear is probably tweaked and needs attention. Shims would just be putting on a band aid.

Many, many thanks for the feedback. You guys are awesome. I’ve decided to get both mains off and send to North Sound Aviation for refurbish. I spoke with Jim Hayton. My big challenge has been figuring out how to lift the plane to remove the gear. Here’s what I finally found out last night...

I have 2 different service manuals for ‘62 and earlier 100 Series Cessnas. Both have an illustration of getting the airplane up in Figure 2-2. Neither of those are appropriate for actually removing the gear. Thanks to Steve Ells for sending me a copy of Figure 2-2 from a 1963-1968 service manual which has the instructions on how to do it. Sheesh. Probably 6 hours of research trying to find this info. I guess Cessna finally figured out by 1968 that someone with a pre-‘63 Cessna might also want to remove the gear.

BirdyinBOI wrote:….. I’ve decided to get both mains off and send to North Sound Aviation for refurbish......

A year later, I'm curious how this worked out--
time required, cost, satisfactoriness (is that a word) of the refurb?

Reading this thread has me wondering if I've done the right thing with my tail-spring in my C180J.

Thus far I've pulled it out and chemically stripped it with the modern gentle stripper, not the 'old yella' that would give you third degree burns in seconds.

My intention was to blast it with glass bead medium and paint it with a two pack polyurethane.

But have I already steered a wrong course?

If I was to send it out for shot peening the tailwheel head would need to be removed. That I believe is glued on. How would one remove that?

Cheers,
Texmex.

If the tailwheel head is still glued on with the original Cessna glue there was a procedure in the manual to wrap it with a heating blanket. I guess it warmed it up gradually to get the glue to release without changing the temper of the head.

How do you know if it's still the original glue? Sorry, I'm not sure how to tell. gentle application of a heat gun might do the trick.

I've seen several airplanes in the field with the heads reinstalled with just grease, seemed ok but it's not per the manufacturer.

Hey hotrod...I apologize for not seeing your question until now. The whole process turned out really great. The 3 racks I built to set the fuselage on was perfect. We crawled in and out of the plane all winter with it sitting on the racks. Much easier than climbing in and out with it sitting on the gear. I used 2” “bundling straps” which I had to order online. No one in town had a ratchet on one end and nothing, just a plain strap on the other. They cost about $15/ea and the quality of both strap and ratchet was great. Jim Hayton did a super job on the gear and I had them back in less than 3 weeks with all appropriate paperwork. He even primed and painted them. The plane was still about 3/4” lower at the left wingtip so I used 2-2024-.025 aluminum shims that I mounted under the inside single bolt on the pilot side. The bolt goes through the shim. Jim told me to use the 2024 as I guess it won’t compress. I cut them to match the shape of the inside end of the gear. About
1 1/4” long. The plane sits perfectly level now. I’m very happy with the result of it all and glad I did it. Here’s a pic of the racks.

Birdy,

I'm glad it works out so well. The rack you designed and built is very very clever! I'll be it you post that on the Cessna forums or Barnstormers you could sell it or rent it for sure. Not that you would want to give it up.

I'm utterly impressed with the ingenuity I continue to see on this and other GA forums.

Great job IMHO.

MW