Elm Self-bow Design Help

[BMorv]

I have an american elm stave that I'm working down and I encountered a problem that's going to interfere with my design plans.  This is my 1st try at a self bow (I've made 6 or 7 other bows) so I wanted to go with something simple and efficient, and do the following: 64" NTN, 1.75" wide until 14" from the end and taper down to 1/2" at the tips.  
The problem is shown in the picture.  When I was working down the stave to get it closer to width, part of the interlocking grain ripped out a chunk of wood.  The chunk is a few inches away from the middle of the stave and there's no way for me to center that section where the handle will be.  The chunk is about 1/8" deep.  That would leave me with 1 5/8" or less of width.  Do you think I should modify my design now that I only have 1 5/8" width or less to work with?  
Keep in mind that this is my  1st self bow, and my goal is to make a bow that I can hunt with (50+ lbs) and that will take minimal set, especially with my 29.5" draw length.  The stave is currently 70" long.  Your suggestions are appreciated.  I already have a few hours invested in this stave, and I'm really hoping to make it into a nice bow.  I cut and split this tree back in April.
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[John Scifres]

You got what you got.  Work it into a bow and do your best.  Don't expect your first bow to meet the expectations you listed.  I suspect you'll end up less than 50# and have a couple inches of set.  But they get better.  Enjoy the ride.

[Mad Max]

You have to build the bow that a stave gives you most of the time.
1-1/2" wide is wide enough.
I hope for good luck for you.

Elm is a good wood
You can heat treat the belly will help

[BMorv]

Ok.  I'll work that gouge out and see what I'm left with.  Hopefully I get more than 1.5".
 
The reason I'm so concerned is that in my previous builds I get pretty minimal set out to 28" draw length.  From 28" to 30" it seems that's where it goes from .5" set to 2" set.  I know keeping it wide is my best bet to minimize set considering that my tiller won't be perfect.

I've started looking at heat treating.  I'm sure I'll have a lot more questions once I get to that point.
 
Thanks,
Ben

[Pat B]

The gouge is on the belly side and shouldn't be much trouble. Lay your bow out on the back but when you cut it out leave the handle area blocky, don't shape it at all until later...ie. when I set up a selfbow I mark the 4" handle in the center of the stave. I add 2" on either side of the handle for the fades then on into the limbs and out to the tips. Leave the tips and handle area wide as marked out but reduce the belly from the fades out at 5/8" to 3/4" thickness for now. Now, see where that gouge is in the stave.  You may have reduced the gouge or maybe eliminated but at least you should be able to see the "bow" in the pre-tillered stave. Post pics at this point and we can figure out what to do then.

[BMorv]

Thanks Pat.  I'm pretty sure I understand what you're suggesting.  I'll post some pics once I get to that point, which may be a week from now since I'll be out of town for work.  
Funny that you responded.  I was reading through your elm static re-curve build along last night.  That's the bow I wish I was making right now.  Maybe one day! Gotta walk before you can run I guess.

[Pat B]

That was the first elm bow I had built and I was totally amazed at how well elm worked. I think it was red elm but I don't think it matters.
 Learning patience is the best bow building tools there is and it goes along with patience while waiting for one to get built.       I look forward to your progress.

[BMorv]

I was finally able to get back to this stave, and I roughed it out to the dimensions Pat suggested.  The belly turned out to be a little wider than the back, so I don't think I'll have a problem with taking an 1/8" off to get rid of that gouge.
Thanks for the info.  I'll post more pics as I progress.    
   

   

[mikkekeswick]

Don't reduce the width yet if at all. you want to keep all your width until at about 20 inches of draw (at your 50# intended weight). once there you can see how the wood is reacting and possibly reduce the width a little then.
I only reduce width if a stave is showing no set at all out to 20 or so inches.
Definitely heat treat it! elm loves a good heat treatment and also trap the back a little if it isn't crowned.
I reckon your finished limb will be just under 1/2 inch thick where your gouge is so honestly don't worry about it. You could run some thin superglue into it so that when you are working that area there is no chance of lifting and making a splinter travel further in.
If you wanted to steam some recurves in it isn't that hard and you still have time  

[BMorv]

Thanks mikkekeswick.  That makes sense.  I'll leave the width as is.  
I have BB1 and BB2, but not BB4.  I'll have to get a copy and read the section on heat treating.  
The stave has a little bit of crown to it.  The tree was about 8" in diameter.

[BMorv]

I got back to this stave this weekend and got it to where the limbs are starting to bend while floor tillering.  The tips where quit a bit off center from the handle so I decided to straighten that out before going any further, considering that this is my 1st self bow and I don't need anymore of a challenge at this point.  I steamed the handle area for about 45 minutes then clamped it as shown.  
I want to heat treat this bow and add a little reflex as was suggested, and my questions is: When should I do this?  A week or so after the bow has returned to equilibrium from steaming or is it okay to do it now?  
I guess I'm confused as to what steam does to the wood.  It seems like it would induce more moisture into the wood, but I've read some post suggesting that it actually dries the wood out.  

       
   
   

[Pat B]

I think steam only adds a little moisture to the outer layer of wood. You should be OK to heat treat it now. You can do it again later if you notice it taking set but do it as soon as you notice it. I like to shellac the back of any bow wood I'm working regardless of how seasoned it is just in case. Shellac is easily removed with a light sanding or a wipe down of alcohol.

[BMorv]

Thanks Pat.  So whats the idea with the shellac?  Is it to minimize moisture transfer?  

One lesson learned in dealing with softer woods is to pad the back of the bow before clamping it to anything.  Got a nice dent on the back where that ipe shim was used     .  I'll fill the dent in with glue and hope for the best.

[mikkekeswick]

Shellac will stop moisture leaving the back too quickly leading to checks.
If you apply steam or a heated wet rag to the dent the fibers will eventually come back out. Google 'repairing dents to gunstocks' for more info.

[BMorv]

That's a cool method for removing dents.  I haven't heard of that before.  I'll give it a try even though one of my dents looks more significant than the ones they were taking out of gun stocks.

[BMorv]

Well the bow broke on me this weekend when trying to heat in some reflex.  I'm feeling quit defeated with my 1st selfbow attempt.  I'll eventually get back to one of the other 3 staves I have, so I would like to get an idea of what I did wrong.  
I'm thinking one of 2 things happened:  the surface of the belly dried out too much causing the break or I didn't get the area hot enough to be bend properly.  
I got the 1st limb reflexed and everything looked great.  The next morning I worked on the 2nd limb and had the break happen 5" from the tip when trying to complete the final bend.  I used vegetable oil since I was mostly correcting and inducing shape.  As you can see the bend was pretty mild so I did something wrong.  I did spent more time on this last bend, so my bet is that I dried it out too much.  

   
 
   

   

[takefive]

I had the same thing happen to me trying to flip the tips on a red elm bow.  I didn't heat it long or thorough enough.  From what I've gathered since then, dry heat bending on white wood is a tricky business.  I only do it with osage now, which takes the heat and retains it so much better and bends easily.
I steam all my white wood bends or corrections now.  I bought a cheap hot plate so I can do it in my basement instead of trying to figure out how to suspend the bow over the stove.  30 to 45 minutes of steaming is enough to flip the tips or straighten a limb side to side.  I do use the heat gun on a medium setting to go over the part that I steamed.  It seems to help lock in the bend.  I let it sit for a few days to bring the MC back up.
Good luck on your next one!

[BMorv]

Yeah that's good advice.  I'm more comfortable with steaming.  
I'm pretty sure I dried the wood out too much on the surface being bent causing the failure.  That shouldn't be an issue with steaming.

[BMorv]

In the meantime I'm going to get started on another bamboo backed/ Ipe as I know I can build one successfully.  Too many failures in a row and I'm afraid I'm going to go into bow building depression.