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Finished composite hickory bow/ pics

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BowEd:
Stick Bender....The mass weight of a bow like this compared to it's draw weight is way too high compared to a turkish horn bow.It would be way overbuilt.In self and backed bow comparisons it is comparably normal 17.40 ounces before leather handle.Especially holding the reflex it does which in self and backed bow comparisons it should weigh 22.00 ounces.The fps readings are all true and accurate.The only thing that accounts for this is the reflex it holds.After 6 hours of bracing it does not show an over amount of soft set when unbraced.Less than 1.5" which tells me it is not over stressed.I believe it has cured more to account for that also.

BowEd:
Got ahold of some graph paper & had pre measured this bow by each inch earlier just as it was tillered and made up this fdc paper.It's a 60" TTT & 58.25" NTN bow.It should say 52.5# @ 27.5".It was measured to 28" @ 53.3# at that time.Close enough for me.I should measure it again.I see I forgot to show the 27" line.No biggie the end result is the same at 28".I corrected it farther along this posting showing efficiency and kenetic energy etc.It's been 2.5 months since these figures were took.It has cured a bit more and is performing a little better because of that.

DC:
I love your bows Ed, they are beautiful. I have a question about the F/D drawing. Do you know what causes the hump in the F/D graph?

BowEd:
DC...Because of the reflex the bow is holding the draw weight starts higher per inch then it levels off[I imagine then the composites go to work and length of limbs too] then it begins to go up again as string angle and strain gets higher.The hump is stored energy the bow has.A self bows' fdc line would be more straight line maybe even concave a bit the way I understand it because they do not store as much energy.
I should of done this earlier to find out myself here but after crunching all of the figures this is what I come up with for bow efficiency and the kenetic energy of this arrow.These figures may be skewed a few percentage points one way or the other too but overall pretty close.
Shooting lighter arrows of course reduces this bow's efficiency as with most bows.Looking at Adam Karpowicz's efficiency ratings of his horn bows as a goal to look at this bow hangs in there close to most of them shooting heavier arrows[12/gpp].Hard to believe I know but there it is.Arrows shot below [10/gpp] the shorter horn bows out shoot and take over in efficiency and speed.The slightest difference in figures transfers to a lot in the field.Now pulling this bow to 30" would make up a lot of difference and by the looks of the graph line it is not strained so much it could'nt do that.Really did'nt take all that long to figure out and kinda fun too.Even for this old farmer.First time actually doing this.In the future making more types of bows when I want to check a bow out thoroughly I can with confidence know exactly what I've got.Just another tool in the bow making tool box the way I see it.

DC:
I made a recurve sometime back and did an F/D curve on it. It had a hump like that but the hump coincided with string lift off. I could understand that, but your bow is past string lift off at brace. I can't understand why the reflex would cause a hump like that. I can understand it causing higher early draw weight but I would have expected an even curve. It's almost like there is an "oil can" in the limb(if you know what I mean?) and it's kind of popping through at that point. I'm buffaloed and I'm rambling, sorry.

I'm taking a closer look and I'm confused. You say 17.6 at 6" of draw which should be 12" on the drawing but the drawing says 18.7. Am I missing something?

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