Restoration of a Vernier Caliper by Electrolysis

Picture CaliperElectro1.jpg depicts an antique vernier caliper in process
of being restored by the electrolysis process.  This required nothing more
than an automobile battery charger, some 20 Mule Team Borax, a plastic
bucket, and a sacrificial steel anode. The process is described in several
websites related to restoring antique tools.

The caliper was purchased at a local flea market for TWENTY FIVE CENTS.
It didn't look too hopeful. The calibrations were completely obscured by
rust.  Both the sliding jaw and the fine adjuster slider were stuck
solidly.

A few nights in the electrolytic bath, with the tool being turned so that
different sides face the anode, plus some light rubbing with steel wool
and Kano Labs "Kroil". (www.kanolabs.com) yielded the appearance shown.

Note the water line near the 11 cm. mark.  This is clearly shows the
"before" and "after" electrolysis. (I did not immerse the tool entirely
so that I could show before and after.)

At this stage, the two slides came free after an overnight soak in Kroil
and a very light rap with a rawhide mallet while the caliper was held
in my hand. (No vise)

The process will continue until all the rust is removed, after which I'll
polish it lightly with steel wool and Kroil.  When I'm satisfied that
the appearance cannot be further improved, I will coat the tool with
Butcher's Wax and it will become a "user" tool for non-critical measuring.

Not bad for twenty five cents and some TLC.

John Ruth