[FWDLK] repairing rusty floors

["richard main" <shelldrakelimited@xxxxxxxxxxxxx>]

I've been having some success repairing the floors in my Plymouths.  I have
a couple of daily driver 55 Plymouth four-door sedans I've been using as
Guinea pigs.  I don't have much body, metal, or welding experience.  But I
did buy a Millermatic 185 MIG-welder and a Lincoln Electric ProStart-55
plasma cutter.   Now I'm learning to use them.

One 55 had rust holes big enough for fingers to go through in a group
around the gas pedal and under the brake pedal.  More were on the floor in
the back seat on the left side.  I used to plasma cutter to cut out the
immediate areas including the rust holes.  These were mostly flat areas.  I
then traced the outline of the cutout on a sheet of 22 gauge sheet steel I
got from the hardware store.  I added a 3/8" overlap margin all around.  I
used the plasma cutter to cut this freeform shape out too.

Next the sheet stock was laid down on top of the cutout on the floor.  Ran
a bead all around the edges.  Used the lowest setting on the MIG welder and
put the wirefeed at 30% of max.  The actual weld puddle was concentrated on
the top of the new pieces outside edge, and this puddle melted down into
the Plymouths original sheetmetal.  Holes that open up can be closed by
sputtering wirefeed on the edges the way a honey bee builds up a cell in a
beehive.  The toughest part of welding was finding the right speed of
progression that would weld the metal but not punch holes.

The finished weld is treated with Metal-Ready and then sprayed with an
undercoating or the "SnoPak" roof mastic they use on the roofs of RVs.
Color pigment can be added to the SnoPak to match the color of the original
factory mastic.

The result looks real decent.  Then cover with padding and carpet that will
not trap moisture in.

After two or three of the lesser Plymouths are under my belt, I'll attack
the 56 Furys with my cutter and welder.

Oh, I found out simple dents in the body can be popped back out 95% to 100%
by heating the dent cherry red with a propane torch, watching it swell
badly, waiting for it to cool for a couple of minutes, and then giving it a
wack from behind with a broad smooth round hammer.  Pops right back like it
rembers where it was supoposed to be.  Access to the back is critical,
because if you can't wack it cleanly, the trick will not work.

Richard Main