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From: Dave Tartaglia <emory!!indy>
X-Source: The Hotrod Mailing list
Date: Nov 1993
Subject: Re: Sand Blasting.
X-Sequence: 6800

Is sand (bead, whatever) blasting suitable for removing chrome from a bumper?
The chrome on the bumpers of my '63 Galaxie is sick; dull, hazy and slightly
pitted.  I don't plan to rechrome but paint them body color, so a perfectly
smooth surface is not required.

[Sand would probably work but I prefer the zero-work method - un-plate
it.  Just reverse the plating process.  Just bag that sucker in a heavy
plastic bag, pour in some suitable electrolyte (battery acid will work)
enough to immerse the part, lay a piece of stainless steel wire near it
but not in contact and apply DC current with the bumper on the positive
lead.  The chrome and underlayments (nickel over copper, typically) will
plate right back into solution.  Actually it falls out as sludge.  The
higher the current density, the faster the de-plating but for something
that large, you likely cannot get anywhere near the optimum current
density so just hook it up to whatever you have that can supply 10-20 amps
and let it cook, making sure the solution doesn't get too hot.

I've never done a whole bumper but I have done lots of smaller trim pieces
this way in preparation for painting.  Works great.  If you let the de-plating
go a bit farther after the last underlayment, it will etch the steel
to a satin finish that gives paint a real good bite.  After the de-plating
is finished, soak the part for a few hours in warm baking soda water to
neutralize any of the acid residue.  JGD]

From: Peter Fazio (WTD/WCD) <emory!ARL.ARMY.MIL!fazio>
X-Source: The Hotrod Mailing list
Date: Mar 1994
Subject:  Re:  replacing springs
X-Sequence: 7877


I have an '81 Malibu that I replaced the front springs on w/o the aid of
a compressor.  I think my Malibu has the same or at least similar front
end as does your '79 Carlo .  Caution : It is much safer to do w/ spring
compressors, but in a pinch it can be done as follows :

First off, I raised that corner of the car and put it on a jack stand.
Next, remove all the necessary thingas in the way, then place a floor
jack under the lower control arm pivot and apply a little upward force
on it.  Now, w/ the lower control arm pivot fully supported by the floor
jack remove the bolt that the lower control arm pivots upon.  After the
bolt is removed, CAREFULLY lower the inboard end (pivot end) of the
lower control arm using the floor jack.  The spring will expand as you
lower the jack.  Do this slowly until all tension is removed from the
spring.  For safety, you may want to chain the spring to a part of the
vehicle just in case the jack slips ( those springs store alot of
potential energy when compressed!!!  ) .  Now, remove the old spring,
put the new one in it's place and start jacking the lower control arm
into place.  Getting it back into line such that you can slide the pivot
bolt back into place sometimes takes a little wiggling, so be CAREFUL
when doing this part.

                                       good luck,


p.s.  Truly, I think it is worth renting a spring compressor
         to do this job just to be as safe as possible.

[I might add that if you have a welder, you can make a perfectly workable
set of compressors in an hour or less.  Each of my compressors (two are
required) consists of a chunk of 1" allthread, a female steel pipe coupler
that slides over the allthread and a couple of pieces of 1"X3/8" steel
strap.  On one end, a piece of steel stock is welded to the end of
the allthread so that it sticks out at a 90 degree angle.  It is then
heated and bent to form a hook.  I use a die grinder to remove most of
the threads from the inside of the pipe coupler so that slides easily
over the allthread.  A ~3" chunk of stock is welded along the axis of
the coupler so that it extends past the end of the coupler.  It is
then heated and bent into another large radius hook.  An appropriate
nut for the allthread finishes the thing.

In use, one of these is hooked over each side of the spring.  A wrench is
then used to tighten the nut which pulls the hooks toward each other,
compressing the spring.  For MacPherson struts where one can gain easy
access to the spring, I made a large wrench by taking a cheap socket,
sawing across it to separate the square drive hole from the socket and then
welding a chunk of pipe the same diameter of the socket in.  This made
a "socket" about a foot long.  I use this with an air wrench to
run the nut up and down on the all-thread.  If you do this, you need
to first de-plate any chrome/nickel plating from the socket, as the
plating seems to make a very brittle weld.  I do this by hooking
the socket to the + side of a car battery, a carbon rod to the (-)
and immersing the two in a jar of battery acid.  The chrome/nickel/copper
plates off and falls out as sludge.  Only takes a few minutes.
And since even cheap sockets are made from some "high alloy" usually
resembling chrome-moly, the assembly needs to be heat treated before
use.  I use our kiln but a torch can do it just fine.  Just heat
it to a dull red heat and then bury it in a pile of vermiculite
or kitty litter and let it cool slowly.  JGD]

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