Primitive Archer

Main Discussion Area => Bows => Topic started by: wkominos on April 18, 2009, 07:01:01 pm

Title: Tillering help
Post by: wkominos on April 18, 2009, 07:01:01 pm
This is my first bow and the tiller looks good to me, but i'm sure there's something i'm not seeing.
Also, how do measure the set of a bow?
Thanks for the help

[attachment deleted by admin]
Title: Re: Tillering help
Post by: Jesse on April 18, 2009, 07:34:19 pm
Both limbs could bend more mid limb and the left limb has a hinge out towards the end. You measure set by comparing the bow before and after tillering
Title: Re: Tillering help
Post by: wkominos on April 18, 2009, 07:37:38 pm
Thanks I'll get to work on that
Title: Re: Tillering help
Post by: George Tsoukalas on April 19, 2009, 02:42:27 am
Congratulations on an excellent first bow. That's awesome. here is what I see while you can still do some correcting. Stiff spot mid limb on both limbs. Left limb is starting to hinge towards the tip actually about 8 inches from it. You really should think about using a rope and pulley too. Jawge
Title: Re: Tillering help
Post by: wkominos on April 19, 2009, 02:59:06 am
Thanks for the help. What do you mean by a rope and pulley?
Title: Re: Tillering help
Post by: DustinDees on April 19, 2009, 04:24:11 am
a tillering tree has notches all the way down it. allowing you to latch the bowstring to any notch as you tiller. the problem with this is you can unintentionally leave the bow drawn for longer periods of time than is ok for the wood. a string attached to the bowstring to the floor via a pulley then to you allows you to draw the bow to marked increments and judge tiller and let strain off the bow just as fast. here is a pic from google images, the pulley isnt shown but is probably attached to the floor or the beam by an eye bolt.

(http://i352.photobucket.com/albums/r327/myownslave/69859286ulUlfm_ph.jpg)

hope this helps.

Dustin D.
Title: Re: Tillering help
Post by: wkominos on April 19, 2009, 04:55:58 am
That is sick I will definitely look into making one of those, thanks for your help
Title: Re: Tillering help
Post by: DCM on April 19, 2009, 08:04:00 am
Looks good to me.  A little stiff mid limb on each.  A little soft on the outer left limb,which would be mitigated by working on the mid limb but remember to stay off of it.

Measure set from it's original shape.  In general terms one measures the distance at the string grooves but a great deal can be learned by the difference in shape, before vs. after working on the tree.  Where the bow changes shape the most is getting worked the most so the places that retain their shape should be candidates to reduce thickness.

I'm guessing your bow shows some deflex on the inner limbs.  Describe it's lenght, width, wood species etc. 
Title: Re: Tillering help
Post by: Eric Krewson on April 19, 2009, 10:26:54 am
Make yourself a tillering gizmo and recheck your limbs. Sometimes our eyes get fooled into thinking we have a pretty good tiller when we don't. You can't fool a gizmo, it is right every time.

Here is a how-to on making and using a gizmo.

http://tradgang.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=125;t=001047
Title: Re: Tillering help
Post by: George Tsoukalas on April 19, 2009, 10:53:50 am
There's also a rope and pulley on my site. See Bow Making Directions. This one clamps in a vice and floor joist and takes down for storage. Jawge
http://georgeandjoni.home.comcast.net/~georgeandjoni/
Title: Re: Tillering help
Post by: wkominos on April 19, 2009, 04:33:24 pm
Thanks for all the help guys. Jawge your site has a ton of really good info thanks. My bow is 52" made of hickory it tapers from 1 3/4" at the midlimb to 1/2' at the tip, it is drawing 37# at 21". I am still a little confused on measuring set, am i measuring from tip to tip after it has taken set and then taking the difference between that length and then comparing that to the original 52"?
Title: Re: Tillering help
Post by: George Tsoukalas on April 19, 2009, 08:41:27 pm
I put the back of the bow up against the wall and measure tip deflection. Don't worry about set at this point in your bow making. IMHO. Jawge
Title: Re: Tillering help
Post by: George Tsoukalas on April 19, 2009, 08:47:05 pm
wkominos, thanks for the kind words and glad you like my site. Jawge
Title: Re: Tillering help
Post by: Jesse on April 19, 2009, 09:25:52 pm
If the bow has reflex when you start you can set the bow on a table belly up and measure the distance between the handle and the table. That way you can see how much you loose. If you started out straight then just set it belly up on the table and measure from the tip to the table. Like George said I wouldnt worry about set or draw weight yet. Concentrate on tillering well and on the next you can set another goal like hitting a certain weight range. Set happens to just about every bow so dont let it frustrate you. My first bow looks the exact same braced and unbraced so you are doing great ;) 
Title: Re: Tillering help
Post by: smokeu on April 23, 2009, 03:19:42 pm
Congrats lets see some updated pics< What pound and draw weight>

mike
Title: Re: Tillering help
Post by: wkominos on April 23, 2009, 03:44:05 pm
I have finals this week so I haven't had any time to work on my bow but i will update soon.
Title: Re: Tillering help
Post by: wkominos on June 01, 2009, 10:09:22 pm
So my bow cracked in the back, I wrapped it in Sinew and retillered it using a gizmo. It is now a 25lb bow. I am now starting on 2 new bows, I'm using a maple board and a osage stave.
Title: Re: Tillering help
Post by: Jesse on June 01, 2009, 10:16:24 pm
Sorry to hear it broke but glad to hear your making more :)
Title: Re: Tillering help
Post by: George Tsoukalas on June 02, 2009, 08:55:02 am
That's the way it goes. You'll get it. Stay with it. Jawge