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Main Boards => The Bowyer's Bench => Topic started by: B-DOG on October 05, 2008, 09:27:00 AM

Title: fixing propeller in hickory stave
Post by: B-DOG on October 05, 2008, 09:27:00 AM
i've got a hickory stave that i was wanting to try to build a bow from. it has what i think is known as propeller. after bow is laid out on the back. the limbs are slightly twisted in the opposite direction. can this be fixed. i'll try to get some pictures later.
Title: Re: fixing propeller in hickory stave
Post by: Pat B on October 05, 2008, 10:13:00 AM
Prop twist can be fixed with heat but it may not be necessary to have a good shooting bow with prop twist. As long as the string runs through the handle the bow should shoot fine. Pictures would be helpful.
  If you want to remove the prop twist, you should get the seasoned stave to floor tiller stage so you don't have too much wood to get hot.   Clamp the stave, at the handle, to a caul with the back down. As you heat the stave from handle out the limbs add clamps and wedges at appropriate places to reverse the twist. After you are done, allow the stave to cool completely before removing it from the caul. I prefer to leave one clamped at least over night.  
  Pat
Title: Re: fixing propeller in hickory stave
Post by: shamus on October 05, 2008, 11:53:00 AM
Pat B is right. A propeller twist does not necessary have to be fixed. As long as the string runs true to the handle, just tiller as normal.

You can do more harm than good by twisting a propeller out of a bow's limb.
Title: Re: fixing propeller in hickory stave
Post by: B M A on October 05, 2008, 04:44:00 PM
Just tiller as normal.  I have a Hickory bow with propeller twist I built about 4 years ago.  Still shooting it today.  Shoots great.  
As shamus said "You can do more harm than good by twisting a propeller out of a bow's limb"
Title: Re: fixing propeller in hickory stave
Post by: George Tsoukalas on October 05, 2008, 05:08:00 PM
Just tiller it. Be sure to look at it from both sides.  Check this. Jawge
http://georgeandjoni.home.comcast.net/~georgeandjoni/aerobow.html
Title: Re: fixing propeller in hickory stave
Post by: B-DOG on October 05, 2008, 08:08:00 PM
thanks guys!
Title: Re: fixing propeller in hickory stave
Post by: Bjorn on October 07, 2008, 11:45:00 PM
That's the beauty of self bows! Work with whatcha' got.
Title: Re: fixing propeller in hickory stave
Post by: Roy Steele on February 02, 2009, 07:37:00 AM
PAT is right it  may shoot alright stwisted.Or if you tiller it right.It may turn out ok.May be twisted unstrung put will be stright when strung and pulled.
Title: Re: fixing propeller in hickory stave
Post by: Roy Steele on February 02, 2009, 07:40:00 AM
PAT is right it  may shoot alright stwisted.Or if you tiller it right.It may turn out ok.May be twisted unstrung put will be stright when strung and pulled.The deer can't see that from his direction.
Title: Re: fixing propeller in hickory stave
Post by: ALW on February 02, 2009, 08:14:00 AM
I've only built 7 or 8 bows so I am by no means an expert.  But I will say that it was easier for me to straighten out the twist prior to tillering so I had a fairly straight stave to work with.  It doesn't take too much time to do it.  The ones I didn't straighten out always seemed to have some tip twist at full draw and the string wanted to ride out of the grooves a little.  But that was probably due to my tillering!  LOL.....

Aaron
Title: Re: fixing propeller in hickory stave
Post by: DCM on February 02, 2009, 08:40:00 AM
Like Aarron, IMHO having right and regular wood (taking the twist out) makes the task of tillering much easier for the less experienced bowyers.  The reason is a twisted limb will not show you the same bending profile from one side to the other.  So during the tillering process one must constantly swap sides, to compare the tiller on one side with the other.  There are other reasons as well.  It definately doesn't HAVE to be done, but one should not discount the notion out of hand.

Than said, some knarly staves will have a little twist even when corrected.  And a selfbowyer might as well bump his head on stuff like this, tillering twisted limbs, as he'll be presented w/ projects where options are limited eventually.