Design Tweeks To Increase Longbow Performence

[arachnid]

Hi guys.

Long time since I posted something.
I`ve been shooting my BBI R/D longbow for about a year and a half now, and I`m really pleased with it.
I want to make another one like it, only better. I want to get more arrow speed (although I have not measured the speed
on this bow- don't have a chrony...) and better performance.
Here are the specs of my current bow:
66" long
1.4" wide at the fade, parallel limb for a about 2/3 of the way, then taper to 1/2" tip.
1/8" thick bamboo backing
reflex deflex design
42#@26"
14 strand B50 flemish twist string

What I`m looking for is the little tweeks and modifications in the design that make all the difference in performence (along with a good tiller, of course).
Looking forward for your wisdom.

Thanks
Dor

[BowEd]

Honestly you should have a chronograph to compare but just using 8 or 9 strands of fast flight for string will give you maybe a good 8 fps increase right off the bat.Increasing performance is done here and there in little bits to get an overall goal.You might try reducing weight on your outside 10" of the tips if possible.I've read every 65 grains taken off tips increases 1 fps.I can vouch for that on a couple of my bows.Readjusting stable good shooting bows long after shooting in is'nt advised too much by me.Leaving good enough alone so to speak.If your really pleased with it you might want to leave it alone.Increasing performance is done making more bows and trial and error.Different designs and above all good tillering like you said.Maybe just ,make another bow a little different.Some other ideas might get shot at ya on here too.That's just my 2 cents worth.

[Bryce]

So your looking for speed?
The only thing I can think of at the moment, narrow the nocks some more. Switch to a 8- 12 strand fast flight string (like beadman said) and lighter weight arrows.

But the best thing for performance is a tiller that tells no lies and is using all the wood to its maximum ability:)

[arachnid]

Thanks guys.
But, as I said, I`m not looking to make modifications on this bow. I want to make a new one and I`m looking for things to change and tweek on this design and apply on my next bow. It`s better then just guessing (I guess... )

[PatM]

Make a recurve obviously. That's why they were invented. 

[bushboy]

Do you have a braced,unbraced and a full draw pic?

[arachnid]

Do you have a braced,unbraced and a full draw pic?

It`s kinda late night now, here in Israel.... I`ll try to take some pics tomorow...

BTW, which wood is better to use as a belly with boo backing- Ipe (board) or Mulberry (self cut, 2 year seasoning) ?

[PatM]

Ipe by miles.

[arachnid]

Ok, here are some pics... notice how the upper limb has a bit less reflex then the lower. I had a bit of de-lamination and I didn`t pay attantion to it and drew the bow- BAD IDEA. Anyway... I wraped it with FG cloth and epoxy (I know Iknow... not primitive. But it`s the best thing I had at the moment). The tiller is far from perfect, I made some improvments lately, causing a 3# drop in draw waight.









So, back to my question- what will be the best design improvments I can make in my NEXT BBI longbow?
And, If I want to make a tri-lam- mulberry belly, ipe core, boo back (I`ve read a few years back that Adam [a.k.a adb] made great shooting bows with osage belly, ipe core and hickory back)- will I get good performens?

Thanks
Dor

[Badger]

   As far as improvements go I can't see your pics. But I would use about 3" reflex and try to finish with 2". Most of your improvements will come in the way of tecnique used to tiller. I like to use the least amount of bending limb that I can get away with but at the same time I don't want t use less than what I need to avoid set. In the case of your bow this would usually mean keep the outer 8" of the limb stiff. I favor using a no set tillering tecnique. If you don't know what that is we can explain it.

[bradsmith2010]

as stated,, string and narrow tips will help alot,, ,, then it becomes more complicated,,

[Swamp Thang]

   As far as improvements go I can't see your pics. But I would use about 3" reflex and try to finish with 2". Most of your improvements will come in the way of tecnique used to tiller. I like to use the least amount of bending limb that I can get away with but at the same time I don't want t use less than what I need to avoid set. In the case of your bow this would usually mean keep the outer 8" of the limb stiff. I favor using a no set tillering tecnique. If you don't know what that is we can explain it.

Yes please or pm me or I dunno trying not to steal his thunder but I'm reeeallly interested

[Marc St Louis]

Also your bow is too long for a 26" draw.  Go down to 62 or 63" max

[loon]

found his thread on no set tillering - http://www.primitivearcher.com/smf/index.php?topic=17294.0
the last paragraph of the first post explains it

[arachnid]

I've posted the pics using google drive but I don't know why you can't see them.
Anyway, I've read the post on no set tillering but I didn't quite get it. So if you can explain a bit more clearly- that'll be great.
Thanks.
Dor