the on-board welder this truck would be stuck on the
To Build An On-board Welder
have several options when it comes to buying a welder for
you're off road vehicle. One is to spend around $825 for a
Link Arc mobile unit. Very trick set up, but not everyone
has that much money to spend on a welder. There's also the
Premier Power Welder which starts at around $399 (not including
the alternator). Then theirs the two cheap home built welders
I'm about to tell you how to build.
Built Welder Using NAPA Parts.
Parts needed for welder:
110-volt power supply---NAPA Part # 782-1757 $90,
or there are cheaper ones to choose from.
Adjustable hand throttle---$53.49 NAPA Part# 731-1132
Welding cable quick connects (male and female). You can
get these from your local welding supply shop for around
You will need a moisture resistant DC voltmeter that reads
0-200 or 0-250 volts.
Some 4 gauge cable (power unit to alternator)
welding cables- this can be very costly depending on where
you buy it from and what type of cable you use. You could
build a cheap set out of jumper cables, or buy it by the
foot at the welding supply store.
You will need a "stinger" and a ground clamp. Stingers
are expensive for the good ones, but Harbor Freight
Tools and Post Tools sells cheap ones for around $10.
Also cheap ground clamps for around $2.
You can also pick up cheap #10 lens welding hoods and
goggles at a variety of tool stores.
Welding rod: The best all around rod to carry is 3/32
6010 or 6011. With this rod you can weld just about any
trail repair up. It is a good rod for penetrating through
paint, grease and dirt. You may also want to carry a few
sticks of Nickel rod for cast irons such as steering boxes,
differential housings, transfer cases, etc. Keep in mind
that you should pre heat these items before welding. A
propane torch will work just fine.
An external regulated Ford type alternator of at least
70 amps. When you purchase the power converter box it
will come with instructions to wire it up to your alternator.
This will not work with GM internal regulated alternators.
It is ideal for Ford type alternators. (note: if you
have a GM alternator read "welder option two")
are some pictures of the homemade welder
the NAPA part # 782-1757 is only the upper left part of
the welder. The rest of the welder is a flat piece of
12 gauge steel with all the other components in the list
a picture of the welder showing the cable connecters plugged
into the fittings.
is a pic of the connecters:
The hand throttle, voltage meter, and welding cable connecters
are all mounted as a unit just for convienance. You can mount
them wherever you want. Keep in mind though, that there will
be wires all over the place if they are mounted apart from
it works: When the power converter is hooked up properly
all you need to do is flip the switch from 12 volts to 110
volts. That will bypass the regulator and allow your alternator
to produce whatever it is capable of (at least 70 amps), and
up to 150 volts! Then you're ready to weld! Just plug in the
cables and get to it! This is also where the adjustable throttle
comes in handy. 2500rpm is a good RPM to start at. Also, the
smaller the pulley on the alternator the faster it will turn,
which means less RPM needed. When the converter is set at
110 volts you can use the 110v outlets to run tools such as:
drop lights, drills, grinders, etc. Keep in mind that all
of these power supplies deliver only D.C. power! Some electric
motors will not operate (induction motors). And fluorescent
lights also will not work. Here are a few other shots of the
welder, notice the one with the light on and the grinder,
that grinder is turning!
"option two": If you have a GM alternator
and don't want to change over to a Ford, here's what you can
do. You can mount the Ford alternator separately and not even
hassle with wiring into your charging system. If you do not
have an extra pully to run the belt off of, you can weld another
pulley to your primary alternators pully and run off of that.
I suggest that you mount the alternator, but leave the belt
disconnected when not in use. If you do not have room for
a second alternator you can simply mount it to your fender
well or something. It's not like it will be hooked up all
the time, so it should be just fine. With this system you
do not need the power converter box, but may want it for the
convenience of the power outlets and such. You only need a
power wire from the battery to the field post of the alternator
to energize it. I suggest you put a on/off switch in between
the alternator and battery. Then run a heavy 4 gauge cable
off the output terminal of the alternator for your stinger.
That's the very simple way to use a alternator as a welder,
it's simple, plain, but works as well as the other type I
Welding: here are some brief instructions on welding
with batteries. First of all, you need at least two car batteries,
but three is better. The reason for this is that you need
about 36 volts to get a decent arc from the weld rod. You
must wire the batteries in a series fashion. You can use a
few sets of jumper cables to do so. The batteries must be
as far away from the welding as possible! Also cover them
with a blanket or tarp incase of an explosion.
batteries: From the first battery, attach a cable from positive
to negative of the second battery. Then from the second battery,
connect a cable from the positive to the negative of the third
battery. Now, your welding rod cable will go from your positive
side on your third battery, and the ground cable will come
off the negative side of the first battery. Your ready to
weld now! Be real careful!!!!!!
will produce 36 volts and about 250 amps. .