yet another question(s)

[eman614]

here is the situation. i have built several laminated d/r longbows in three different lengths. of the three the shortest has the least hand shock, and the longest has the worst. also if you were to draw a parallel line with the very front of the riser the tips of the shortest would land directly on that line, and the longest would extend past that line by two inches. has anyone else had similar results? if so do you think it was a result of a shorter bow or do you think it had to do with the relationship of the tips?

and for the next question. if i was to make a shorter bow say 58in , but use a form that is shaped much like the one i already have, that makes a 62in bow, could i then use a riser that is shortend to say 14in and still use the same lam stack thickness? the length of the working limb would not change so it would seem the stack shouldn't either.

and another ?  would this be a good situation(with the 14in riser) to use a power lam?

thanks for looking. any and all input is appreciated.

eric

[bjansen]

Eric, I have noticed as well...the shorter the working limb the less hand shock (or at least the easier to remove handshock).  I made some 68" mild R/D bows and the handshock was noticable and hard to remove..but I could get there on most of them.  It seems like any short limbed bow I make shoots good right out of the form, without even beginiing to tiller it.  

So I think it had to do with the shorter limbs.

[Jason Scott]

How much deflex is in the riser? More deflex in design reduces shock usually.

I don't think the two inches net reflex is hurting you. There are a lot of good shooting bows like that.

I think there will be some change in # by shortening the riser because of the way the limb loading will change. The string angle should be greater so that has to change something. Not sure though. I'd like to know how that works. I have seen where bowyers offer the same limbs on a short and long riser TD but don't recall the difference in draw or performance. Seems like it might stack more. But that doesn't mean not to try it. Great Northern has a couple bows with short risers in the 60" range that are very popular. They figured it out with their bushbow and critter gitter.

The power wedge will essentially negate shortening the riser. The benifit to the power wedge is that you can get a longer feathered taper that is hard to get by grinding the fades of the riser. It should soften shock more than just a riser of the same length though. But in the same breath you are taking mass weight out of the riser which should increase perceived shock some. I don't use power wedges. For now I don't think the benifit is worth the effort as long as I can get good long paper thin fades.

[eman614]

thanks for the input so far. this is going well. i hope more people give there input.