5. Lineup smaller parts like ditcher teeth or coal
1. Use the oxy-MAPP method for hard-facing thin
cutter bits in a row for easy pm-heating during
cutting edges; electric arc welding is more apt to
bum through. oxy-MAPP is also preferred where
minimum dilution is required.
6. Clean all areas to be hard-faced with a grinding
wheel regardless of whether the part is new or
2. Most small parts made of low-, medium-or
used. Grinding helps eliminate pin holes and
relatively high-carbon steel can be hard-faced by
makes it easier to apply the hard metal. The
the oxy-MAPP process. The hard-facing of cast
ground surface should always extend beyond the
iron is not recommended.
hard metal deposit. In other words, if the hard
metal deposit is to be 1 in. wide, the ground area
3. Use a tip approximately four sizes larger than that
should be 1-1/2 in. wide.
ordinarily used to deposit a mild steel rod of the
7. When you hard-face any type of an edged tool you
increase its thickness. It is therefore desirable to
4. Where possible, use a jig to quickly position the
draw out or sharpen all types of edged implements,
part for downhand welding, especially when the
new or used, before the hard metal is deposited.
part must be turned two or more times. This will
save time and gas.