board bow tillering

[Dan Jones]

I am working on a maple board bow,and I'm getting close to the tillering process. I understand that one starts with a "long string" and then moves to a string sized to fit the bow length.  My first question is when do you stop using the long string and shift to the other string? Should you tiller all the way to the desired draw length with the long string and then go back and start over with the second string? If not, at what point does the change of strings occur?

A second question - is there a good video of the tillering process on line?    Thank you.

[Wolftrail]

Should you tiller all the way to the desired draw length with the long string and then go back and start over with the second string?   Nope..!

I floor tiller as much as possible to get it bending evenly like full length.  Then brace it for about 3" or so.  dont go beyond your target weight  and keep scraping till it looks even.  I usually tiller out to 24" or so then shoot it in.

[Bowjunkie]

You just want to use the long string until the limbs are bending far enough that you can get it to a low brace height. If you're going to brace it to  3 or 4 inches, use the long string until you get nice even bends with the limb tips moving several inches behind the handle. I usually go to 8 or 9" with the long string, then brace low, check the new profile with the outer limbs bending more, make any fixes, and start drawing to 8 or 9 again. If it looks good, gradually increase brace height, and keep on going.

With the long string, don't try to get the outer limbs bending as much as the rest of the limb. Due to the different string angle, they automatically bend more when you brace it with a shorter string.

In respect to this physics phenomenon, the 'long string' should be just an inch longer than the bow's length, just long enough to get it on the bow without flexing the limbs.

[George Tsoukalas]

I long string tiller out to 10" of limb movement. I keep checking the weight and look to get target + 5 # about and then string it for the first time. Of course, I want good limb movement also. Jawge

[Eric Krewson]

If you use a Gizmo, go to the short string when you can run the gizmo up both limbs with the same pencil setting (1/8") and not make a mark except for the last 8" of the tips. Leave your your tips stiff because of the different string angle of the short string.