Again when tillering the bow NEVER draw the bow further then the desired draw weight. Using the marks on the main bow again you measure down to the elastic stretched from nock to nock on the main bow. You want the last six inches of the main bow tips to have minimal bend if any. All the bend should be in the lower and mid sections of the main bow limbs. The radius of the bend of the back bow is not of much concern. If it does not rock to one side or the other things are fine. I try to get it's minimal bend to look right but it is the tiller of the main bow that will tell you if all is well.
Do not be suprised if when tillering the main bow togther with the back bow you find some interesting changes. The back bow will force the main bow to shorten which forces the mid limb area of the main bow to "bow" out. This is not going to be found on a more convential bow. Once every thing is even with the upper limb bending about 1/4" more then the lower limb, and we are within 3 to 4 pounds of our desired draw weight it is time to sand the bow out and start finishing.
Oh yes one morething you might be intrested in. I was talking to Don Pummel at LL Beans the other day and he is thinking about having me do a talk and demo on building these bows. If you would be able to come you might want to let him know as he is looking into it and seeing how much intrest there is out there in primitive archery.
