Author Topic: Acid Damage and Buffing out  (Read 1267 times)

Offline RichardL

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Acid Damage and Buffing out
« on: 02.02. 2008 15:32 »
Since we are not having a flurring of "A"-specific discussion right now, I thought I would talk about part of the work going on while my engine is at the machinist.

This last summer, one of my "shake down" rides proved to be just that. I got home to find that the battery hold-down strap shook loose and acid had splashed out. The extent of splashing was not great, but enough to be annoying. Basically, it got on my inexpensive shorty mufflers, a little on the rear rim, a little on rear fender stays, a lot on the backside of the oil tank and some on the fender. Besides being annoying and disappointing, the damage done by the acid was a little surprising. Anywhere it touched chrome it left marks. Anywhere it toched air-temperature paint it wiped off with no damage at all. However, where it touched the back side of the oil tank below the oil line it left nasty black streaks. The difference between above and below the oil line was really obvious. It was clear that the heat of the oil accelerated the chemical reaction between the paint and the acid. I suppose, in time, the acid would have attacked the colder paint, but I avoided that by immediately giving the bike a bath of water and baking soda (I don't know if the bath also stopped the bike's itch). Thankfully, the only black streaks in the paint were on the back side of the oil tank, where I scuffed-up the paint with a little sandpaper and used a spray can with a close color. Unless someone can get his head between the battery and the oil tank, I don't think this touch-up will ever be noticed.

Now, on with why I decided to write. Yesterday, I set out to clean up some parts, in preparation for reassembly. I took chrome polish to the mufflers and got no results in removing the acid marks. Without much hope of success, I decided to try buffing them out using a buffing wheel on the bench grinder. Well, this worked much better than expected. I was using a buffing compound formulated for chrome. With time and elbow grease, working on the acid marks paid off. While they did not completely disappear, they became much less noticable, except by very close inspection. I believe what happened is that the oxidized and corrosive appearance due to the acid attacking the chrome was removed, exposing the nickel beneath. At the same time, the nickel and adjacent chrome got polished to near equal luster. This was a satisfying result. While I didn't care that much about the nearly disposable shorty mufflers, it let me know that I can (with a portable buffer) go after the marks on the stays and rim with expectation of some success.

As a result of this near-debacle, I have changed over to using a sealed gel-filled battery. I also now use tie-wraps between the battery hold-down straps and the frame, to avoid losing them again. Even though they are now after-market, they are not free.

Richard




tanknj

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Re: Acid Damage and Buffing out
« Reply #1 on: 02.02. 2008 17:56 »
Just a guess but maybe baking soda would have helped ? I didn't think acid would mar chrome.

Offline RichardL

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Re: Acid Damage and Buffing out
« Reply #2 on: 02.02. 2008 20:32 »
The bike got the water and baking soda bath to nuetralize any acid left over after the wipe down.  The bit about the "itch" was a joke referring to a bath one might take to relieve, say, poison oak.

Yes, the reaction of acid on chrome is really fast.