Investment
Cast
Forged
Muscleback
Cavity Back
Quick Comparison
Investment Cast
A "positive" or master model of the clubhead is
made, usually made of aluminum, which contains all
engraved markings, scoring lines, and even the hosel
hole. Wax is injected into the master, which yields a
positive "wax" clubhead. The clubhead is then
dipped into ceramic several times to produce the negative
mold. The wax is then melted, and stainless steel poured
into the ceramic mold. When the ceramic casting is
removed, you have the clubhead ready to be painted.
Forged
Forging a club is very similar to what the village
blacksmith used to do. Dies are "sunk" or cut,
by milling the desired impression, and forging is
accomplished with a "drop hammer". The
manufacturer is then presented with a raw forging, which
is a close approximation of the clubhead desired. The
clubhead must then be finished by milling, grinding and
drilling.
Muscleback
A Muscleback iron, also known as a "blade", has
generally been associated as a "forged" iron.
While the manufacturing process isn't really important,
the design of the clubhead is. The muscleback iron
distributes the weight evenly throughout the entire head,
producing a small "sweet spot" in the center of
the head. This is to say that a shot hit in the center of
the face will produce a longer, straighter flight
trajectory. Shots which aren't hit pure (off-center) will
produce a shorter, unpredictable flight trajectory.
Cavity Back
A cavity back iron, also known as perimeter weighted, has
generally been associated as an investment cast iron.
Again while the manufacturing process isn't really
important, the design of the clubhead is. The cavity back
iron distributes the weight around the perimeter of the
head, producing a large "sweet spot". This
makes the off-center shots more forgiving, flying longer
and straighter, than an off-center shot with a muscleback
iron.
Quick Comparison
Investment cast
- Usually a Cavity back
- Peripheral weighting, if cavity back
- More forgiving, due to cavity back
- Stainless steel
Forged
- Usually a Blade or Muscleback
- Central weighting, if a blade or muscleback
- Better "feel", due to muscleback design
- Carbon steel & chrome