a pair of small pliers and pull in
opposite directions. Thin brass sheets
can be scored with a utility knife and
metal straightedge, then snapped off.
Use two or three light passes, cutting
against a maple chopping block, birch
board, or glass backing.
Drilling holes in brass with a pin vise is
a slow process. The solution is to mount
a handpiece for flex-shaft machines in a
hobby drill press. Several companies
manufacturer this tool and it is worth
the cost. When working with brass, use
a 1/4” or thicker piece of maple or birch
for backing. (Avoid softwoods, as these
flare the exit hole.) To prevent the bit
from wandering, mark the spot with a
small center punch. Lubricate the bit
with light oil and drill slowly to avoid
breakage. Keep rpms under 2,000, or
excessive heat buildup will also break
the bit. Caution: The brass will become
hot, so clamp the pieces to the drill
press table or hold them down with a
wooden stick. Do not touch the brass!
Solder: Until recently, modelers used
pure silver solder to avoid the corrosive
qualities of lead in soft solder. Today,
many solders are lead free. They’re
composed of tin and antimony, are
strong, and melt at less than 450º F.
Some brands are mixed with 3% or 4%
silver, but still melt easily. Consequently,
no reason exists to use pure silver sol-
der (melts at 1300º F).
Flux: Purchase pure solder and buy flux
separately for additional control. Paste
fluxes apply more precisely than liq-
uids, which run to all the wrong places.
Soldering: The key to soldering is keeping
the brass clean. Use a solvent, lightly
sand, or both. Once the parts are cleaned,
don’t touch them. Your fingers will leave
greasy spots. Soldering is easy if your
work is set up properly. First, immobilize
the parts in a fixture or other holding
device, then add just enough flux to the
joint to do the job. Remember, solder
flows where flux is applied.
Next, cut a small piece of solder and lay
it on the joint before heating.
Experiment with various sizes to learn
how much solder it takes to just fill a
joint. The joint should look like the real
thing, not a big glob of fillets. Heat the
joint with a small torch or pencil solder-
ing iron. This sequence is important.
The larger the parts, the longer it takes
to heat the brass and melt the solder.
Remove excess solder with needle files.
7
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