Hi Michael,
I would be glad to talk with about branch flutes, et al. In case you would be interested...branch flutes are my thing...can't claim to be NA other than through DNA... Like that branch you are working with.
Rand
Catahoulaflutes.com
Just in case anyone is wondering where the branch flute is I plan on calling Rand this weekend sometime to get some pointers. I want to make sure I'm approaching it in a way that will work before I cut my other hand off (even though he's not NA)
Just kidding Rand, I look white as a feather when you put me up against all of my relatives on my Moms side. I'm only a quarter and all of my cousins and full blood buddies pick on me as the token white guy in the bunch
One of my Comanche friends said you Chickasaws have it all wrong you are supposed to show up covered in your enemies blood not your own, after he saw that pic of my hand.
Here is where I am at on the board flute
Use a 5/32" drill bit at the largest if you want to only drill one hole or a smaller bit to drill 3 - 4 holes to get your sound edge and air chamber flue started. You can use the marks you laid out on the flute to approximate where your sound edge and the exit for your slow air chamber is going to be. If you were like me and routed with crooked eyes make sure that you find the center according to your bore mark it and drill on both sides of the 7/8" area I wrote about earlier. The photo below shows the bottom, but drill from the top using the marks I am talking about. It's not critical if you get a little bit off, just don't get to crazy with your hand drill or drill press and you will be fine. The drilled holes are prep for where you will be carving out your sound edge and flue.
The air chamber is important and the sounding edge is critical at this stage, so make sure to do a good clean job of carving it out. Make sure to get the whole channel clear of any splinters that might cause the air to shift one way or another while you're playing. You can see in the diagram I posted that both the air chamber flue and the sound edge are angled about 30 to 35 degrees make sure not to forget to angle it because that will give a nice crisp sound that you can sustain with light or heavy breathing.
Sometimes I put a bevel in the top of the flue and sound edge but it's not necessary; I tend to bevel if I compress the wood just to clean it up a bit. If you do compress the wood don't press down too hard and damage the sound edge or flue, I also soak a little ca glue in those areas just to harden it a bit on these softer woods. If you're up to it you can inlay a tougher wood into these areas for the same purpose.
Once you have that all cleaned up you want to oil the inside of the flue and sound chamber before you glue it up, just be careful to keep away from the areas that will be glued together. I've started using general finish butcher block oil with beeswax melted into it, but have also used an olive oil beeswax mixture, so that no one is kissing an oil that may be funky. Just make sure you don't use something that might chip off or toxic since you're putting your moufff up gain' it.
Here are the halves after they've been oiled up and the edges cleaned off with some Everclear, at this stage I slap on some titebond 3 and put the inner tube wrap on it. I like to use old bike inner tubes or some sort of heavy packing wrap, because It's easy to over tighten clamps and end up cracking your flute and it puts even pressure all around the flute so you get a nice clean glue line.
Didn't get a shot of the wrapped flute yet cause I went to bed right after I got to this point.