my hemp backed Hazel bow has lost weight and gained set!?!

[George Tsoukalas]

Yes, that does make sense.

Here is another possibility.

Sleddy, while tillering out the stave did you exercise it 10-20 times after each wood removal?

I am thinking that you may not have  and it finally caught up to the stave.

Jawge

[sieddy]

Hi Jawge yes I do exercise the limbs throughly throughout tillering.
PD & Pat l- I agree entirely that I should have left it a little longer. But I only started playing with the bow last night and the backing was bone dry this morning when I pulled it off!?!

[PEARL DRUMS]

So, did you register that heavier weight AFTER you backed it, or before?

[sieddy]

I'm not being defensive I appreciate that this is my mistake i am just interested to learn from it. I have maximum respect for the support that is available on this great forum!

[sieddy]

I was getting the heavier weight before I put the backing on

[Jodocus]

500-1000 shots. Most of us build too many bows to even hit that number with a good share of them.

yeah, only my favourites and giveaways make it past 1000 arrows.

[mikekeswick]

I think you'll find that the hemp is too stiff for the not too great in compression hazel's belly.
The stiffness of the backing has caused more of the bows 'load' to be shifted to the belly causing the extra set.
100% that's the reason. Remember to make the resistance to tension/compression the same in any and every bow you make.
Trapping is done for the same reason eg. to help out tension strong compression weak woods, heat treating is the same but unfortunately you've increased the strength of the back gving the belly no chance. The lost weight and set tell the story.

[sieddy]

Hi Mike thanks for that it's really interesting. I didn't think hemp would be too strong but when dry it was like fibre glass (very tough!). Anyway as I was putting it on I was thinking "there ain't no call to be backing Hazel!"
Looking on the bright side only put it on as an experiment prior to using it to back an Elm and a Yew bow.  I've learnt some valuable lessons before getting into those more valuable peices of wood!
The Hazel bow is now pulling 40#@26" and has about 2.5" of set. So I can have some fun shooting targets in the backyard with it anyway