Guys, i am going through the proceeds of designing and making a long bow form that can be adjusted to give you anything from standard straight long bow design through to a heavy reflex/deflex design, what i would like to know is what would be consdiered the maximum amount of reflex/deflex, then i can design it back from there.
Any input would be appreciated.
Thanks
Shawn
Adjustable Bow form
Moderator: Moderators
Re: Adjustable Bow form
Hi Shawn,
Observations from my own experience, other bowyers may have obtained different results.
To comply with the existing longbow definition the following may help as a guide.
Parallel laminations up to about 25mm.
Tapered laminations [depending on the amount of taper] up to about 50 - 55mm.
Limb width and the amount of taper to the string nocks will have a bearing on the degree of curvature in the limbs of the braced bow.
Hardwoods such as spotted gum do not seem to come around as easily as hard rock maple, hickory or bamboo.
Daryl.
Observations from my own experience, other bowyers may have obtained different results.
To comply with the existing longbow definition the following may help as a guide.
Parallel laminations up to about 25mm.
Tapered laminations [depending on the amount of taper] up to about 50 - 55mm.
Limb width and the amount of taper to the string nocks will have a bearing on the degree of curvature in the limbs of the braced bow.
Hardwoods such as spotted gum do not seem to come around as easily as hard rock maple, hickory or bamboo.
Daryl.
"And you must not stick for a groat or twelvepence more than another man would give, if it be a good bow.
For a good bow twice paid for, is better than an ill bow once broken. [Ascham]
“If a cluttered desk is a sign of a cluttered mind, of what, then, is an empty desk a sign?” [Einstein]
I am old enough to make my own decisions....Just not young enough to remember what I decided!....
For a good bow twice paid for, is better than an ill bow once broken. [Ascham]
“If a cluttered desk is a sign of a cluttered mind, of what, then, is an empty desk a sign?” [Einstein]
I am old enough to make my own decisions....Just not young enough to remember what I decided!....
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Stickbow Hunter
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Re: Adjustable Bow form
Shawn,
I can't help with the amount of deflex or reflex as I don't build that design of bow. Also please check what you mean by reflex/deflex as I assume you are really meaning deflex/reflex (limbs bend toward you at the handle and then reflex away from you in the outer part of the limb).
All the best with your bow building and please keep us up to date.
Jeff
I can't help with the amount of deflex or reflex as I don't build that design of bow. Also please check what you mean by reflex/deflex as I assume you are really meaning deflex/reflex (limbs bend toward you at the handle and then reflex away from you in the outer part of the limb).
All the best with your bow building and please keep us up to date.
Jeff
Re: Adjustable Bow form
I would be most interested to see the finished form which is flexible enough to produce a straight bow and various bows with different amounts of reflex and deflex, and yet strong and rigid enough to withstand the pressures of clamps or an air hose at 60psi.
At 60 psi the hose is rock hard.
Don't forget that your stave, clamped in the form, must be cooked in a hot box. If you remove the stave from the form to cook it, it will lose its shape and in all probability, the limbs will twist.
At 60 psi the hose is rock hard.
Don't forget that your stave, clamped in the form, must be cooked in a hot box. If you remove the stave from the form to cook it, it will lose its shape and in all probability, the limbs will twist.
Norman
Draw, anchor, loose.
Draw, anchor, loose.
Re: Adjustable Bow form
Sorry, deflex/reflex the new hybrid style bows. What i want to do is build a traditional style longbow for myself and also have a go at a newer hybrid style. I may make one with a mate if it all works out right to get him away from the training wheels. I was going to go about and get a form cut out on a CNC router cutter but then went on to think about the idea of aluminium rectangular tube that was cut in strategic places to allow it to bend and be held down by a lot of bolts, that were easily adjusted. Something like the bed bolts used in furniture making.I can get all the raw materials for next to nothing. It is getting the design out of my head and into something realistic that is the problem.
Re: Adjustable Bow form
The only form which I have seen which may do what you want was made by a German woodwork teacher. He published an article on making a laminated bamboo reflex/deflex longbow in 'Primitive Archer' and it was available on the net until about three years ago. It was a brilliant idea and is probably used on cabinet making to form things like laminated curved arms for lounge chairs.
He drew the shape he wanted on a large flat sheet of something like chipboard or MDF. at various points along the curve he screwed blocks of wood to the sheet. Then he shaped his stave by applying glue to all the surfaces and clamping them to the blocks so that the stave was at right angles to the sheet. When the glue dried the cured stave was the desired shape.
He did not state whether he cured his stave in a hotbox. But it should not be too difficult to cut a narrow piece of MDF, chipboard or plywood , about 200mm wide which could be placed in a hotbox with the stave clamped to the blocks.
He drew the shape he wanted on a large flat sheet of something like chipboard or MDF. at various points along the curve he screwed blocks of wood to the sheet. Then he shaped his stave by applying glue to all the surfaces and clamping them to the blocks so that the stave was at right angles to the sheet. When the glue dried the cured stave was the desired shape.
He did not state whether he cured his stave in a hotbox. But it should not be too difficult to cut a narrow piece of MDF, chipboard or plywood , about 200mm wide which could be placed in a hotbox with the stave clamped to the blocks.
Norman
Draw, anchor, loose.
Draw, anchor, loose.
Re: Adjustable Bow form
for bamboo backed bows the most versatile system I have seen is Dean Torges adjustable form on his dvd http://www.bowyersedge.com/
I have even used this to make bamboo back and bellied bows.
I have even used this to make bamboo back and bellied bows.
Ed Lomax
http://www.bujinkanadelaide.org.au/
http://www.bujinkanadelaide.org.au/
Re: Adjustable Bow form
i personaly am going fot 1"deflex than 3" reflex gives it a damn nice shape
and for your form set a lage base (say as long as youer longest bow) made from thick plywood (MDF etc will warp if u use a hot box, which you dont have 2) and every few inches say 6" have small holes in this plywood base where u can screw in diffrent lengths of timber with the holes for clamps to be the adjustable form.
Easy as that.
so your form could be as ajustable as you want it to be
and for your form set a lage base (say as long as youer longest bow) made from thick plywood (MDF etc will warp if u use a hot box, which you dont have 2) and every few inches say 6" have small holes in this plywood base where u can screw in diffrent lengths of timber with the holes for clamps to be the adjustable form.
Easy as that.
so your form could be as ajustable as you want it to be
Im gonna make it bend and break-Fall Out Boy