patch to the hole. This patch will be
butt-welded; the better the fit, the
better the weld. I can fill tiny gaps
when welding, but if there is any
part that overlaps, that’s a deal-
breaker, so the test-fitting shows me
where any additional trimming may
be necessary.
I was having a good day, and
the patch matched the hole exactly
with no overlap. In fact, the fit was
so good that the patch held itself
into place without falling through.
If your fit-up is not this good (and
mine is not always perfect) it’s OK
to use magnets or tape to hold the
patch for tack welding. A couple
of caveats, though. A magnet may
interfere with the welding arc if you
get too close, and tape can leave
sticky residue that will foul the
weld, so keep these points in mind.
Once I was satisfied with the fit-up,
it was time for the tacking.
I used a TIG welder, but the
process is the same for any welding
process. I used a water-cooled
torch with a #7 cup, fitted with
a 2 percent seriated^3 ⁄ 32 -inch-
diameter tungsten, sharpened to
a fine point. I set the flowmeter
to 15 CFH of Argon. It takes a
minimum of 45 amps to make a
puddle on 18-gauge steel, but I set
the machine to 80 amps, so I was
running at about “half-throttle”
with the foot pedal that controls
the heat. This allows me to add a
quick burst of extra heat if I need
to. The first tack goes in the spot
with the best fit-up—where the
patch is perfectly flush with the
base metal and has little or no
gap. A small tack is made, using
0.035-inch-diameter ER 70 S-6
wire. With the first tack in place I
look for the next-best fitting spot
06 The first tacks are placed where I have
the best fit.
07 After a few tacks are made, I work the
entire joint with a hammer and dolly. My
goal is to align the metal for the next tacks,
and if there are any gaps, they can be
reduced by hammering on-dolly.
08 There are several repetitions of tacking
and hammering, until the tacks are no more
than^1 ⁄ 2 -inch apart. The closer the tacks, the
better it stabilizes the patch, keeping the
metal aligned as the weld is made.
This 1966 Chevy C20 Service Truck is the kind of build that makes you
stop and take notice — it’s as unique as it is impressive. Builder Travis
Prius of Gardnerville, Nevada, started fabricating cars at 16. Today,
his shop, CTP Concepts, is emerging as a top shop for custom classic
builds. Travis never hesitates to chop up a body style and get creative.
Custom is a craft, he is a master, and it’s all fueled by three simple
words:
TRAVIS PRIUS / builder
UNIVERSAL RETROFIT CUSTOM
DETERMINED
517.424.0577 | WWW.IDIDIT.COM
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