What makes a bow "smooth" drawing?

[Tom Anderson]

I've been trying out all sorts of different bows lately and have noticed that some of them just seem to draw back smoother than others - that is, fairly linear increase in draw that starts out soft and increases in poundage until I hit anchor.
Some bows that were equivalent in draw weight(at least they were marked that way) felt entirely different in the draw, but nothing appeared different regarding cast.
So, what makes a smooth-drawing bow?  Choice of wood? Limb design? Etc.?

[nyamazan]

I have always wondered this myself.I only own one longbow, and not a well known or custom type bow so have nothing to compare it to.

The only thing I can think of is when looking at custom /good make bow reviews in our local magazine I see the draw/force curve is not linear. It seems to increase rapidly, poundage per length, and then smoothen down towards the 30" draw length.

Don't know if I've explained that clearly!

[The Singing Bowyer]

A smooth draw comes from creating a bow that has an equal amount of weight gain throughout the draw....EX. 3 or 4 lbs per inch. When a bow "stacks" it usually takes on additional weight per inch at certain point(maybe 5 or 7lbs)

Different things can effect it...but, in the case of selfbows that I shoot, it seems that how well they are tillered and the length of the bow can play a major part...

[Otto]

Actually, a bow is "smooth" to draw when the force/draw curve IS linear.  It's when it's NOT linear that a bow feels as if it's "stacking".

One thing to consider.....until you get out past 30 inches or so....MOST bows made today are fairly linear WRT draw weight/length.  Many times, when someone complains of a bow stacking, what they are really feeling is finger pinch.  That can get uncomfortable on the fingers and it gets translated to the brain as "stack".

Something to think about when a guy tells you that Brand X bows stack....then states he has a 27 inch draw.  Nah bubba Nah...that ain't happening.

[KYArcher]

Bamboo!

[James Wrenn]

A bow has only so many inches from brace to draw length to build weight.A bow with a lot of prestress at brace will have less weight per inch to gain to get to the end weight and will be smoother at the back end of the draw.A bow that is drawn farther will have more distance so will have to gain less weight per inch of draw.If you take two bows the same weight and one has a real tight string at brace and the other feels soft the tight one will be smoother at the back end.The softer one will have to build up more weight to get to the same weight.

[Mike Mecredy]

Several factors on the bow design make it smooth drawing.  With many longbow being made these days they aren't much more than an inch wide.  The limbs width taper from the riser gradually down to the tips, and with the narrow limbs that require them to be a bit thicker than the wider limbs. (say 1 3/8" wide) This makes the bow feel solid at the begining of the draw and stack more gradually through out the entire draw so it isn't as noticable.  Coupled with the length of the riser the limb design makes the draw more consistant.  

If a longbow has wide limbs, say around 1 5/16" to 1 3/8", the limbs will be thinner and tapered along the entire length but more so at the last 8 inches.  This makes the the bow draw easier at the begining and heavier toward the end resulting in a more noticable stack.  This is characteristic in most recurve bows today but it isn't exactly a bad thing.

Like James said; the thinner, wide limbs the string won't feel as tight brace as the narrow thick limbs will.  But it's all a matter of prefeerence;  I've heard some say the narrow limbs are smooth and some say the wider limbs are smooth, but on all the bow tests they rate smoothness by an even draw force curve,   Characteristic of the narrow thick limbs.