The only version of the Penobscot design that has the back bow strings go over the tips of the back and then attach to nocks near the grip is the Micmac War bow. All other Penobscot bows have the back bow strings on nocks at the tip of the back bow.
The graph is a comparison of the force draw curves for a static recurve Penobscot bow with the draw weight set at 60 and 65 pounds (Solid lines). The dotted lines show the curve for a 55 pound flat bow and the one that shows let off is a 60 pound Martin Warthog compound. The numbers at the right of the graph represent the # of squares (Stored energy) below each graph. Penobscot bow at 65 pounds = 166 at 60 pounds = 139 The 60 pound Warthog = 137 and the flat bow = 105.
When I did the graph I was rather suprised at the results. Bye the way Bowmo, that is one cool looking Penobscot bow and the tiller looks great!
One tip on tillering these beasts, I have it works best if you make the lower limb on the main bow 2" longer then the upper limb. If a limb is going to take a set it will be the lower limb. I will try to pst a few pictures of the different bows.
The brush nocks on the static recurve are my addition, this bow is Osage and the brush nocks are Claro walnut. The next bow down is a slight recurve made of Hornbeam and is the bow that was on the cover of Primitive Archer Magazine. The bottom bow is a mild reflex deflex. The next picture is the bow I made for Kracow Archery befor it had any finish on it. This bow got a sinue bow strings as the origionals had but I am sure the sinue was not from the back of a moose as the origionals were. This style is the second oldest and the main bow is a pyramid design flat bow and the back bow is flat with no reflex. On the oldest style the main bow was a more conventional design sort of a modified Mear Heath design and the back bow wae longer(2/3) the length of the main bow. These bows also had the lightest back bow which bent parallel to the main bow. I will try to post a picture of one.