How to best clear axle rust

So I bootied a cam the other day and the axle/lobe interface was rusted enough to lock in 1 of the 4 lobes on the Metolius ultralight. I've soaked the head in WD40, and broken the lobe free from the locked position it was in, but the rust within is still holding the lobe in place making it unable to move freely without forced effort (using pliers). Anyone have any homebrew remedies for dissolving rust in an area where you cannot scrub it free with steelwool as you would on the surface? WD40 seemed to help a little as did some elbow grease, but I'm at a standstill getting the lobe to move freely under the spring tension, and trigger use. Any tips?

My tip: be sneaky, mark it just like one of your partner's cams, and swap it when s/he isn't looking. Or throw it away.

You could try soaking it in some coke or Pepsi for a while. The acids should leave the aluminum alone but slowly dissolve rust.

I've heard that Coke/Pepsi works but never tried it personally. Some things I have used:

A penetrating oil like "Marvel Mystery Oil" instead of WD-40. Soak overnight, exercise the lobes once in a while.

Snap "Rust Buster" in the spray can.

Ooh ooh I know,

YOUR GONNA DIE!!!

Never got to say that on here before. Sorry, got nothing helpfull to say.

wivanoff wrote:A penetrating oil like "Marvel Mystery Oil" instead of WD-40.

I have to deal with metal joints and pivot points all the time at work. Best I've found so far is "Free All". Works much better than the old standby of "P B'laster" and smells much better too. Usual caveat of keeping it off of the slings, etc apply. Spray a bit between the axle and lobe, work it a few times and let it sit for 1/2 hour or so. More than likely you might have to do that once more, but I would guess that it will move freely after that.

I had all but given up on a Metolius ultralight just like yours - it was old and frozen. WD40 got it pivoting, but not enough to be springy. I tried everything, finally saturating it in an unknown brand of spray bike chain oil and working with pliers for a half hour or so. I don't think it was the particular lubricant as much as the repeated motion, but it's now springy and smooth.

From what I've learned about aluminum alloys, I would be careful about what I soak my cams in. It is possible the metal could suffer stress corrosion cracking.

The summary of my entire education is freely available:
en.wikipedia.org/wiki/Stres…

It might be difficult to spot if the cam is already corroded.

Edit: You might have to be hanging on the cam while it is immersed in the corrosive agent for this mode of failure. But still, think about it.

So the WD40 soak worked! took about 4 days for the rust to dissolve to a point of letting the springs naturally return the cam lobes to their original position after using the trigger bar. I'd spray the head with wd40 every other day, and then use pliers to rotate the stuck lobe. After which I just let the cam chill out on a paper towel. Now she's good as new.