new form outlines

Radius, I think the last two angles are far to steep. They would make the bow instable. The first seems to be ok, but the kasan/ siyah transition could be a little more rounded.

JJ

I think the same, you need more radius.

Sorry, could not resist!

Daniel

thanks guys. I of course plan to round out the corners to avoid any abrupt kinks in the core. I will balloon the kasan a little more on the first one, and leave the other two for now.

on the other hand... what if i attach a long wedge to the sal section of the form? that would decrease the angle

In a strung bow, the string should not touch kasan, only the base of the tip. If the string sits on the kasan, the bow will be very difficult to stabilize (will twist), unless the brace height is impossibly high, or you will be forced to add bridges. Try to imagine the bow strung, bearing in mind that the tip and the outer half of kasan are rigid in the finished bow.

The form on the third picture is an extreme example of this problem. The first form looks best, but it will be even better if the first couple inches below the base of tip are straight (keep the arms of the angle straight with only the apex rounded). Then the string will clear the kasan as it should. The other angle of kasan/sal can be opened with heat later if needed.

Adam

[external image]


This is the one a couple of you thought might work, but with a bellied-out kasan, and also a flattened area about 2" long where the tip ends and becomes the kasan.

Look any better?

No. Very curved kasan. Happy new year ! :lol:

Make the kasan straight and round the tip / kasan bend a little more. Good luck

some ideas of my jigs, as recommended the kasan part should be straight


Jig 1 and 1 limbs without ears
Jig 3 complete limb with sal, kasan/ears

Reto

Great stuff, Reto!

what do you think of these forms?

http://www.youtube.com/watch?v=Ut7njjTz ... ature=fvwp

very easy, just uses 2 clamps

i tamed this pair down. So far it's the only pair i've cut out. No need to rush it.

[external image]

Pacific yew slats, air dried, soaked in water for several days before boiling and bending. I left them several inches too long, to give me leverage for bending them. In order to achieve the kasan/tip transition i was forced to use c-clamps and press the laths flat against the form. This resulted in one of the laths splitting open lengthwise. I filled it with glue last night and squeezed it shut.

Next i measured 3" up from the k/t bend and marked the end of the bow. Then, from mid-kasan, i measured 18" toward the tip to give me the length of horn. that gives me the center (allowing for the insert), from where i can measure back to the exact spot to cut the lath to length.


[external image]

[external image]

[external image]

[external image]

Looking good :) How thick are the yew slats at the kasan/tip-bend? They look impressively thick. Bendy stuff.

they are damn thick. 13/16" or 22 mm. I know it's crazy how much yew will bend with a little persuasion from hot water. Sometimes you just press it, and it goes WOW! and then next thing you know....setback handle, easy recurve, what have you. This was the most difficult shape i've achieved yet with yew, these were both dense, solid pieces, and it fully required the use of the c-clamp at tip/kasan. Couldn't have done it otherwise. But it went.

I'm stoked.