There are 2 basic lamination shapes; parallels and tapers. Parallels
stay the same thickness from one end to the other, whereas tapered laminations
are thick at the butt end and get gradually thinner as you move towards
the tip. There are several different degrees of taper available, .001"
per inch, .0015" per inch, .002" per inch and .003" per
inch. A .001" per inch taper will loose 1 thousands of an inch in
thickness for every inch closer to the tip that it is measured. A .0015"
taper will loose 1½ thousands and so on. The amount of taper in
a 36" long lamination, that tapers .001" per inch, will barely
be noticeable, whereas a 36" taper that is .125, or 1/8", at
the buttend will be paper thin at the tip in a .003" taper. What taper
in a bowlimb does is create a bullwhip effect, theoretically snapping the
bowstring taut and thereby increasing efficiency. It also makes the limb
"open up" smoothly. Too much taper in a limb, depending on the
design, can cause a bow to stack, however. Some bowyers prefer a combination
of tapers and parallels, some prefer all tapers and others all parallels.
Experience will dictate your final preferences and opinions.
No subject can get a healthy, sometimes heated, discussion going between
bowyers more than the pros and cons of various limbwoods. What I'm going
to do here is state my personal opinions on a variety of woods. These are
my opinions and are almost sure to cause discussion and debate, but what
the heck, I enjoy living life on the edge.
The modulus of elasticity data is from the U.S. Forest
Service Wood Engineering Handbook.
| Red elm: A proven limbwood that has good recovery speed, is
relatively inexpensive, is readily available and has good cosmetic character
especially when used flat grain. Can be used in both longbows and recurves
with good results. Modulus of elasticity is 1.54|
| Osage orange: Another proven limbwood with excellent recovery
speed. It seems to me to be a little harsher shooting than most woods.
It isn't as easy to find good quality osage as it is red elm, but still
readily available. It is a bright orange-yellow which darkens with age.
Modulus of elasticity is unknown.|
| Black locust: An excellent limbwood, although I don't find
it especially pretty, it is easy to get. Modulus of elasticity is 2.05|
| Honey locust: A relatively heavy and hardwood that can have
an attractive color and figure. Not as common as black locust. Modulus
of elasticity is 1.63|
This wood is looked down upon by some bowyer for a lot of reasons,
however has been used quite successfully in a lot of bows. It is easy to
get and can be very pretty especially when it is curly or quilted. Modulus
of elasticity is 1.83|
| Black walnut:
I believe that this is an overlooked limbwood and that it makes a good
shooting bow. The only disadvantage I find with it is that because it is
so dark, it shows the flaws in the clear fiberglass more than most other
woods. Modulus of elasticity is 1.68.|
I believe that all of the above woods are quality limbwoods and can
be used in both longbow and recurve limbs with good success. I am sure
that several of you have noticed the absence of Pacific Yew and
Bamboo from the above list. This is because I have never used them
in a recurve and from all that I have read and gleaned from alot of other
bowyers, their durability in recurves is in question. They are of course,
excellent longbow limbwoods with a proven track record and many ardent
Some exotics that I have used as full thickness laminations are Zebrawood,
Canarywood, Bubinga and Purpleheart. Veneers of approximately
.025 thickness, of other exotics that I have used or have seen used, are
Australian Lacewood, Bocate, Cheechum and Cocobolo.
Since we are discussing laminations, I will breifly mention fiberglass.
The two types of fiberglass most commonly used in traditional bows are
made by the Gordon Glass Company. These two types are Bow-Tuff
and Uni-Glass. Bow Tuff is made with woven glass strands and
Uni Glass is made with lineal glass strands. Uni was developed to help
alleviate the white spots and cosmetic flaws sometimes found in Bow Tuff.
Unfortunetly, Uni can occassionally develop small cracks. Bows are being
successfully made every day with both types of glass.