hypothetically speaking

[sailordad]

hypothetically speaking.(or maybe not)

if one was making a bow from hickory that was 62" ntn and it was at floor tiler and bending about 6"-7" inches on the tiller tree.
lets say that one limb was showing a little set,could it be possible to remove it by heating and putting on a form then finish the tillering and then
heat treating the belly. could this help in keeping the set from coming back to severely?

just curios

thanks

                                                                               peace,
                                                                                      tim

[Badger]

  Sailer, If I picked up set so early in the tillering process I would want to make sure I identified the problem, could be high moisture, mistake in tillering or just an underbuilt design. If the bow wasn't pulled past it's intended draw weight I doubt tillering was the problem. If moisture was the problem heat treating and then letting the stave dry out might very well fix the problem. Steve

[islandpiper]

Funny thing.  I sawed out a red oak blank last week.  the board was straight and true.  I marked and sawed the outline of the back.  everything was fine. 

Then, I sawed extra wood off the belly on both limbs and BANGO , it had set.  The bow was about five feet long and the set, instantly, was probably 3/4 " each end. 

Well, i went ahead and carved the bow, at the local Renaissance Festival, hand tools only, surrounded by the normal crowd.   Had fun, answered lots of questions.   the bow is still curved.  Figure I'll take it in to work tomorrow and toast the belly side while it is clamped in a long anti-stringfollow-curve. 

So, from my experience, you don't even have to begin to bend and tiller and there can be "set". 

piper

[sailordad]

when i make a bow i use a digital caliper and measure every three inches starting at center out on both limbs.
they are both the same thickness within about .050 of each other at all points and most are within .005,
now this does have a slight prop twist to it.widthe wise at all point they are about .060 or less differance in width.

now i dont have any pics of it before i started on it or current(as of yet).
the set is in one limb only,the stave is plenty dry,tiller is even on both limbs according to my gadget.
it hasnt been pulled past intended weight etc.
if i remebmer right one limb had a slight reflex and he other had a slight deflex. either was less than .50 inches
i dont recall which limb was which,however neither has reflex now.
could this just be normal considering the orignal shape then?
if so could i get away with like i asked, heating,reflexing in a form(slightly),ad then continue tillering as normal?

thanks


                                                          tim

[Hickoryswitch]

I think I know exactly what stave your talking bout. How wide are you making it? How many pounds you shootin for? If it's plenty dry I would Toast the belly and add around 2 inches of reflex.

[David Long]

Piper, I would not call what you observed set. Set is something you induce by bending wood past a state where strictly elastic behavior is exhibited, in other words you've entered the inelastic, or plastic zone. When you did your thing to the oak board you revealed a property of that specific piece that had nothing to do with its elasticity (necessarily).

At 6 or 7 inches of bend, and seeing truly inelastic properties, I'd be real worried. On the other hand if the "set" is something like Piper observed, perhaps the wood is good to go forward.

Dave

[Pappy]

What Steve said. Hickory has to be dry. :)I always put mine back on the form and heat treat the belly,usuall when I get it out to 18 or 20 inches of draw and close to the weight I am looking for.
It really dose help.
   Pappy

[Ryano]

You can't get hickory to dry. Heat treat some reflex into it and throw it back in the heatbow for a few days. You'll be sorry if you don't. Wet hickory will completely colapes on you.