Wood
Metal
Graphite
Oversized
Metal with Composite Face
Wood
There are basically two types of wood used, persimmon and
maple.
- Solid heads are usually persimmon.
- Laminated ("plywood") heads are usually maple.
Persimmon heads are made by using a sophisticated turning machine. The process is much like making a duplicate key for a lock. The second, and most commonly used, wood is laminated maple. Generally, 1/16-inch veneers of maple are laminated together much like a sheet of plywood. Then the veneers are heated and pressurized, and finally turned like the persimmon heads. While many golfers indicate that they have a more solid feel at impact with persimmon heads, studies show no support of this. Other golfers prefer the laminated maple, reasoning that they last longer.
Metal
Investment cast metal heads have gained popularity,
mainly because of the added control of peripheral
weighting (which was not a true design goal, but a
product of the casting process to achieve proper weight).
The stainless steel heads are cast hollow to restrict
excessive weight, and usually filled with polyurethane to
muffle impact noise. Metal "wood" heads have
also been noted as adding distance to center and
off-center shots.
Graphite
The same material that is used for shafts is also used to
make graphite heads. There are two subtle variances in
manufacturing techniques. In one case, the graphite
prepreg is mixed with an ABS plastic, and is injection
molded into a head. In the second version the prepreg is
given an epoxy base and the mixture is compression
molded. Graphite heads are manufactured with the same
weight as the wood and metal heads, but are generally
much larger than conventional heads. This increases the
size of the "Sweet spot". No tests yet have
proven graphite heads to be more forgiving or longer than
other materials.
Oversized
The general consensus is that "oversized"
heads, generally made of stainless steel or graphite,
create a larger "sweet spot". This produces a
longer and straighter flight trajectory on off-center
hits. When using stainless steel, the walls of the head
must be made thinner to keep the overall weight
"normal" (191-205 grams for a 1 wood). This has
caused some metal "wood" faces to
"crush" or dent. For this reason, some
manufacturers are bringing "Mid-sized" metal
woods to market, which allows the "sweet spot"
to stay large, yet keeps the walls of the head thick to
prevent denting.
Metal with Composite Face
In conjunction with "oversized" clubheads,
manufacturers are starting to use "face
inserts" (normally plastic, graphite or lightweight
metals). This allows them to produced the larger sized
heads without worrying about the face crushing or
denting. This also allows them to keep the overall weight
of the head down. Face inserts, in metal
"woods", is a fairly new design, and tests
regarding their playability and forgiveness have not been
published.