NetNews Usenet Archive 1992 #23/NN_1992_23.iso/spool/rec/autos/tech/13817

Internet Message Format | 1992-10-09 | 1.6 KB

Path: sparky!uunet!think.com!ames!agate!hafnium.cchem.berkeley.edu!avk
From: [e-mail] (Tony Konashenok)
Newsgroups: rec.autos.tech
Subject: Re: electronic rustproofing.
Date: 9 Oct 1992 22:07:31 GMT
Organization: University of California, Berkeley
Lines: 18
Distribution: world
Message-ID: <[e-mail]>
References: <[e-mail]> <[e-mail]>
NNTP-Posting-Host: hafnium.cchem.berkeley.edu

Yes, this method - cathode protection - is absolutely safe, legal and convenient.
It has been used in vessels (esp. tankers) for many years. In a car, the most
practical way is to screw magnesium bolts into unused holes, like ones for a
trailer hitch, or, if you don't have them, to put magnesium washers under bolts
you can easily remove, like those holding the bumper brackets. Once in a while
take the ohmmeter and check the resistance between magnesium and body; it should
be as low as possible, preferably < 1 ohm. If it is higher, remove it, sand and
reinstall. Generally, the method works better if the car is initially new or
rustless. Otherwise, the resistance between different body parts is high enough
to make your protection inefficient. Check your car's nose-to-tail resistance
to get an idea. The higher it is, the more points of cathode protection you need.
Some cars may have some body parts insulated from the rest of the body. These
parts need magnesium of their own.
--
Tony Konashenok   [e-mail]   [phone] (home)
University of California, Berkeley                 [phone] (office)

Strauss research group, Latimer Hall, UC Berkeley, Berkeley CA 94720, U.S.A.