Gear legs again?

[n2582d]

Do NOT use chemical strippers on your gearlegs when stripping for paint unless you KNOW the specific stipper will not embrittle the steel. (Some strippers cause hydrogen embrittlement.

I've been using Napier SV-35/PMA (Aviation Grade) stripper. On the label it says, "SV-35/PMA is NOT Hydrogen Embrittling ASTM F 519-93". It's "non-hazardous", "non-toxic", and "biodegradable". The drawback is that it is designed to be used with piston or diaphragm spray equipment. But if only stripping the gear a brush would work fine.

[Daniel96D]

I am seriously considering removing the gear legs and having them inspected on 2696D on the next annual since I instruct in her (last year over 300 hours of dual give in my 170). Would any body have any recommendations on where to send the gear (also a quick turn is important since I make a living with the old gal).

[GAHorn]

Daniel, ...perhaps you haven't read the entirety of this discussion thread? (See the previous page, where minton wrote:)

...There is a guy out there that is FAA certified to inspect, shot peen and recertify gear legs. North Sound Aviation, Jim Hayton, 360-661-3302. I know he has come up before and he is as slow as Mole-asses, but if you are serious about this use him.....

[lowNslow]

In all fairness, Daniel did specify a "quick turn". Most anyone who has dealt with North Sound will testify that they are not a quick turn operation.

[OTIS]

Question on the gear legs. The checklist for the Annual states;
"Check torque on main gear leg wedges"
Can't find any information on what the "torque" value is.

gerry
1952 C170B N8072A

[blueldr]

Why not strip the paint and magnaflux the bottom end around the axle bolt holes. Thats the only place I've ever seen one break.
I guess the upper end could be magnafluxed too, but I've never seen one with a problem on the big end.
Some of the tri gear legs had a corrosion problem under the clamped on step, but that would not apply to a C-170 gear.

[mit]

Why not strip the paint and magnaflux the bottom end around the axle bolt holes. Thats the only place I've ever seen one break.
I guess the upper end could be magnafluxed too, but I've never seen one with a problem on the big end.
Some of the tri gear legs had a corrosion problem under the clamped on step, but that would not apply to a C-170 gear.

You best read post #1 in this thread.

[blueldr]

So now I've heard about one, but I still haven't seen one. That's the first one too. However, I've seen a number of lower end failures where the indicatons were that the gear leg had been cracked between the bolt holes long enough for the crack to have rusted before the ultimate failure.

[n2582d]

So now I've heard about one, but I still haven't seen one.

Here's what I found when I pulled my gear. It's beyond me how someone could paint over this without addressing the problem. The pitting is .020" deep. Anyone have a pair of lady leg or 180 gear for sale?

[lowNslow]

Gary, it looks likes the gear was moving in the outboard gear bracket to create that wear, how did the bracket look?

[c170b53]

I think George came up with a figure for allowable damage for Cessna spring gear and I'd ask him for the specifics. I would look at those figures and the specific gear they relate to, to determine the allowable damage to your specific gear. Depending on the thickness found at the damage location and the percentage of material removed its likely the damage can be blended out and watched rather than replacing the leg. In my opinion it's a case of knowing the devil you have versus the other one.

[bagarre]

What's the process to jack up a 170 so that the gear legs go slack? (In order to check them for movement)

[cmsusllc]

I use an engine hoist hooked to the engine, works great.
Scott.....53B

[c170b53]

That would be a bad idea for your crankcase if you're using the engine lift ring as the attachment point to lift the entire aircraft.

[jrenwick]

From the 170B owner's manual:

The airplane may be lifted by a sling around the aft section of the fuselage and sling attached to the engine mount-to-fuselage attachment fitting. The cowl upper half must be removed for application of the sling at the engine mount-to-fuselage attachment fitting.

The 170A owner's manual says you can lift by "lifting lugs on the engine," but this was dropped when the 170B manual was published. Maybe Cessna engineers had second thoughts about it!