bamboo hickory pyramid bow

[svenole]

Hi,im going to make 2 bamboo backed hickory pyramid shaped long bows.im going to use epoxy to glue the bamboo to the hickory,and one thing dont like is the bamboo i have is only 1 1/2 in. wide.i normally go from 2 in. and end at 1/2 at the nocks.one thing i could do is leave the bow straight for 6 in. and then start the taper to the nocks.what do you think?

[JW_Halverson]

Uff da!  Vat happened, Svenole?  Didja cut it twice and it vas still to narrow?

[svenole]

No i ordered it from 3 rivers archery,it came that way 1 1/2 inchs wide .....

[JW_Halverson]

I have no idea how you are going to squeeze 2 inches of width from it.  Looks like you are going to have to settle for 1.5" wide at the fadeouts.  Give yourself a few extra inches of length from your usual design to compensate for lack of width and you may avoid picking up much set. 

[svenole]

yes it will have to be 1 1/2 in....ill have to go thicker than normal........hickory 3/4 ...then the bamboo and ill have something work with..........right? handle 1 1/8 ....2in. fadeouts straight for 6 in. then tapered to 1/2 or 3/8 in at nocks.

[JW_Halverson]

How about some basics, like your draw length and what draw weight you are interested in hitting?

[svenole]

draw 28 in. 50# or 55# wieght

[JW_Halverson]

I think if you give yourself 66" or even a little more, a pyramid bow starting at 1.5" wide at the fade outs would be just fine. 

Now the boo is stronger in tension than the hickory is strong in compression.  That means you will want to be very careful when tillering to NEVER pull more than the weight you will want when the bow is finished.  In fact, don't pull more than 40 lbs in the tillering process until you are down to the final push to hit draw weight and draw length!  That's going to help prevent picking up set. 

Then, you may want to consider a cross section on your limbs of a trapezoid...also known as "trapping the back".  Make your belly 1 3/4 wide at the fades and 1 1/2 wide on the back.  This will give you more hickory on the belly to resist compression. 

Take all this with a grain of salt, or maybe a 2 lb container of Morton's Iodized Salt since I have never built a boo backed hickory bow.  But I've played one on t.v.

Any of you 'boobackers wanna chime in here?

[kevinsmith5]

I have a bamboo backed hickory that I just finished two weeks ago after seeing someone selling one. I was really just doing it as a "will this work" but it turned out well. It's 1 1/2" at the fades and tapers to just over 1/2". The hickory is just over 1/2" thick at the fades. It actually pulls 70 lb at 28" so I don't think you'll have any trouble getting your draw weight, however mine is 70" NTN (due to my 31" draw). If I could change one thing in how I made it it would be to have filed in slightly more reflex. I reflexed it 3/4" in glue up (actually the form was 1 1/4" but that's how much held) and after two weeks of regular shooting I'm at 1 1/2" of string follow. Even then it's still easily the best bow I've done (so far).

[svenole]

thanks guys

[MWirwicki]

Geez, wish you woulda posted this 2 weeks ago.  I had some bamboo strips that were over 2" wide.  I made wooden spoons outta it.   

[RyanY]

If the backing is only 1.5" wide but you want it 2" wide max then just trap the belly lam from the edges of the backing.

[bushboy]

Have made a number of bb bows,would estimate it to triple the draw weight.It is prone to crystal or even frett out the belly,so trapping the back is a good idea!fastests bows I have made to date!think my favorite is a bbelm 72" long 55@28 elb for target shooting.

[svenole]

thanks for the info!!!!!!!!!!!!!!!!!!!!!!!!