ELB help in tillering

[davesouris]

HI all.  My first post here and wanted to thank all for the great source of information.  I have been trying to build some longbows for myself and family and have issues with string follow.  I am making trilam bows with hickory back, red oak core and Maple belly.  3/16, 3/16 and 1/2 belly, 66" nock to nock, 7.5" brace height.  The bows seem to shoot fine and i have made some from 38# to 50#.  the issue is there always seems to be a hing at about 14" from center of the bow when the bow is unstrung and about 2.5 to 3" of set. I am adding a 1/4" piece of maple on the belly 7" long for the riser area and fading that out to the rest of the belly and tapering to the tips.  any suggestions why so much set and hinge?  Maybe I am tillering to hard at the beginning?  I have since made less of a thick riser so that there is a bit of bend in the riser secion.  Here is a pic

 

[davesouris]

Not so sure how to add a pic directly here.  I just have the link.

Dave

[fujimo]

I would not call that a hinge, but it may be working harder there than the rest of the bow, some quick questions first
1 how wide is the bow
2. Are you getting off the long string and onto the short tillering string as soon as you possibly can, long strings will lie, cheat and steal
3. Are you holding it under drawn tension for extended periods of time while studying it.

 Now I don't think that is a huge amt of set, considering your woods, but it can be reduced.
Are you glueing in a bit of reflex.

Looks good though,  they are shooters!!!!

[mikkekeswick]

Your brace height is too high. ^ inches maximum is way kinder to a wooden bow.
The hickory will be overpowering the maple belly. Ipe, osage or something great in compression is needed for the belly of an elb.
Don't use an added belly lam at the handle.
Just glue your stave up at 1 inch thick total.
Taper from 1 inch outside of handle straight to the tips in thickness.
Width taper should start about 4 inches from the handle on both limbs. Taper to 3/4 inch 8 inch from the tips then into 1/2 inch tips (you can go narrowe once you've got the hang of it and depending on belly wood).
Your bow is bending way too much close to the handle. The tiller on an elb should definitely be elliptical. The lower the weight the more elliptical it should be.

[davesouris]

Thanks Mike.  I cant seem to find Osage but could get some ipe.  So after looking online at some longbows I cant seem to figure out how thick they are at the handle.  For example the Bickerstaffe bows.  To help me understand things, the handle area is based on the centre of the bow, so I have my arrow pass mark at 1/2" above centre and the grip area below that.  I am allowing 4-5" for the hand to grasp that part.  so should the tapers be based on the bow centre of the grip center? Or are you saying the handle should be centered on the whole bow and be, say, 9"? this is the area I am not sure of.  I was adding the extra lam to make the bow thicker for the hand but I suspect this was a mistake.  I was also trying to get a full compass on the bow which I should have tried to go more elliptical at 28" draw.

[mikkekeswick]

No the typical way to lay out the handle is to find center. Mark one inch above and three below. Shorter limb is the lower. Have your arrowpass one inch above center.
Thickness taper either starts at the handle edges if I want it bending through the handle if I want the handle a little stiff then I start the thickness taper 2 inches from the edges of the handle.
I should have said that although i'm getting out of it now, making wood bows for other people was my business. I have spent about the last few years making ,almost exclusively ,longbows (English). I read an article by Bickerstaffe where he stated that ipe isn't suitable for making bows.....however that is a marketing ploy on his behalf....Hickory/Ipe will make a superb bow.    I also glue them up with a couple of inches of reflex, make sure there is none around the handle , a little midlimb and then increasing progressively to the tips. Like I said before though the important part is your tiller make it elliptical and as you tiller use any set the bow takes as a guide to where it's working too hard.
Good luck!