New bue from a 7000 year old design

[Mad Max]

 

[Pat B]

I just low braced the bow(used push/pull) and put it in the tree with the bow scale. She pulled 33#@22" so that works out to about 45#@26" maybe a bit less. I still have a little adjusting to do but the levers are long enough I might pike it an inch or so on each limb which will bring the weight up some. She does seem to draw pretty smoothly.

[Bryan Adolphe]

  That is nice to watch! Incredible skill

[Buemaker]

Very good, getting there.

[Pat B]

Almost there! Should be ready for finish work soon. 

[Pat B]

Well, I'm having trouble with the lateral stability. She keeps wanting to pull one way, I'll move the lever over with heat and she wants to go the other way. I need to let it cool again and see where we are.
I may reduce the length of the levers and see if I can make that work.
I may have gotten too complicated with this simple design. 

[Pat B]

 I hit a bump in the road on this bow. It developed a hinge at the fade for one of the the lever.       
The body of the bow, the sinewed area is still in good shape but I want to figure out, over the next few days where to go from here. My options are to add an underlay at the lever fades on both limbs and retiller or shorten the levers all together and make it a short, 50" straight limb sinew backed bow. 

[Pat B]

I've decided to go with a patch. I have a thin piece of osage but I didn't want the contrast and I think it would be too stiff. My next option was a thin piece of ERC but I didn't want to chance that. Then I picked up a piece of the elm from this bow, sawed a thin piece out and flattened and smoother it with the belt sander.
 My next decision was glue. Should I use some Unibond Roy sent me or TBIII. I went with the TBIII because I wanted to glue it up at room temp. I was afraid of introducing heat for curing with the hide glue/sinew backing.
 I ground the patch flat then ground the area to be patched making sure I took just enough off to get a flat surface and made sure the patch and patch area glue surfaces mated well. I buttered both glue surfaces with TBIII and with a stiff backing over the patch I clamped with spring clamps. I'll give it at least until tomorrow for the glue to set then I'll see what I've got. After that I'll re-shape the patched area and see if it worked.

[DesM8]

This kind of thing is so cool to see.  I really appreciate you taking the time to post both the good and the bad.  It's almost more valuable to see the decision making and thought process that goes into fixing problems than it is to see a build process that goes perfectly smooth.

[rainman]

Unibond will set at room temperature.  Just not as fast as Titebond.

[Pat B]

Jeremy, if you are going to build wood bows sometimes you have to consider all possibilities and solutions. I've done similar things when I had a bow fret badly on the belly. I ground down the belly and added a new belly lam making what would be smoker wood into a very usable, good shooting bow. I've not done it on a small scale like this but there is no reason for it not to work if I did my part and continue to do my part correctly.
 "Passing it on" is where I got my bow building knowledge from others so I'm just passing it on. With digital photography it's pretty simple to do these days. 
 I know Unibond will set at 70 degrees but our house isn't at 70 degrees mostly this time of year. I know the TBIII will work so I went with that.

[Buemaker]

I am sure you can do it Pat. Are you going to sinew wrap the patch?

[Pat B]

I wasn't planning on it Bue but that will depend on how it turns out. Other similar patches I've seen were now wrapped but I'll wait and see. It's not out of the question.

[Pat B]

Bue, I will have a wrap at the tip end of the patch. It ended up near where the rawhide ended and I had planned a wrap there.
 I removed the clamps and exposed the patch...


then took the bow down to my shop to reduce the patch and blend it into the limb. I started with a rasp working along the edges to shape the patch to the outline of the limb...


then started reducing the patch thickness working from inside to out as not to snag and rip up the patch...



once I got the patch reduced I started using a scraper for fine tuning. no pics of that but here are the results...



Now, I'll wait another 24 hours to allow any moisture from the glue to evaporate before straining the bow on the test flight.   More to come...

[Mad Max]

 

[Pat B]

I shaped the patch and retillered the bow. Got her on the tree out to 26" then decided to put a few arrows through her. She is pulling just over 45#@26" and is pretty snappy shooter. She's about 61" t/t. After 25 arrows the unbraced reflex is about 2 1/2" and after relaxing she holds 3 1/2". Here is the full draw pic on the tree...


I still need to shape the handle and tips and add the finishing touches.

[Mad Max]

Awesome pat

[onetone]

Pat that is a fine save! Nice work. I am wondering, when you build a self bow like this do you tiller to the center of the bow?

[Pat B]

Thanks, Mark.
 Joel, most of the strain on a bow's limb is at the fades because of the leverage of the limbs so tillering from mid limb out first then bringing the bend back into the fades at the handle is what I try to do.

[Mad Max]

Pat that is a fine save! Nice work. I am wondering, when you build a self bow like this do you tiller to the center of the bow?

Like pat said
When you start working to get the fades bending some, the mid limb out gets stiffer, so more scraping all the way out.
So a continuous tiller check and scraping