Primitive Archer

Main Discussion Area => Bows => Topic started by: ssrhythm on February 26, 2022, 10:40:12 pm

Title: How much natural reflex…
Post by: ssrhythm on February 26, 2022, 10:40:12 pm
Is too much?  I have a c shaped beauty of a stave with a huge knot smack in the middle.  I should be able to make the handle where the bend around the knot will allow for smack-dab center shot and a really comfy-ergonomic grip.  I’m just wondering if there is a such thing as having too much natural reflex to start?  It is pretty extreme.
Title: Re: How much natural reflex…
Post by: ssrhythm on February 27, 2022, 12:21:06 am
To be more specific…even if I could manage to pull off perfect wood removal with perfect cross section symmetry, if I start with too much reflex, will crushing of belly cells not be inevitable at some point on a bow made to be drawn 27-28 inches?  Same issue with the back…at some degree of bend, a self backed bow has got to give, right?  So, is there any way to start out with 7”-9” of reflex and make a 62”-64” bow without severely crushing belly cells and without overstressing the back.  The back issue does not worry me too much , as I can always put a rawhide or sinew backing on it.  The belly crushing is more of a concern. 

I’ve seen a thread about this before, and I seem to remember the consensus being “why take out of a stave what most people try to put into a stave,” and I think the consensus was to work it as is best you can and let whatever set takes place happen.  That’s going to be my plan at this point, but I just wanted to see if anyone has had personal experience with severely, overly reflexed staves and advice about the best way to proceed with it.
Title: Re: How much natural reflex…
Post by: Badger on February 27, 2022, 01:39:42 am
   My feelings are that if you get a good piece of wood, keep the handle and fade section short and do a perfect job tillering you can get away with more reflex. Mark St Louis sometimes uses a lot of reflex. I have been able to establish that putting in extra reflex can potentially backfire if it takes too much set even if it leaves you with 4" reflex. More set creates more hysteresis. I would prefer to put 4" and hope to keep 3". 
Title: Re: How much natural reflex…
Post by: bownarra on February 27, 2022, 02:06:57 am
Yes me too. I prefer to start with no more than say 4". Too much even if you manage to keep a good amount can end up with a sluggish bow as the belly has lost its snap.....but then you have to factor in the particular piece of wood....some wood can take it!
Title: Re: How much natural reflex…
Post by: Eric Krewson on February 27, 2022, 08:15:23 am
Another thing about too much reflex is it will fool you on hitting target poundage poundage, the limbs won't bend so you take off more wood, then they seem to bend all of the sudden leaving you below poundage.
Title: Re: How much natural reflex…
Post by: mmattockx on February 27, 2022, 11:07:01 am
To be more specific…even if I could manage to pull off perfect wood removal with perfect cross section symmetry, if I start with too much reflex, will crushing of belly cells not be inevitable at some point on a bow made to be drawn 27-28 inches?

Yes. It doesn't matter how the reflex got there, having the nocks ahead of the handle adds stress to the limbs when drawn and the bow will be more likely to fail or take a bunch of set.


Mark
Title: Re: How much natural reflex…
Post by: BowEd on February 27, 2022, 11:52:10 am
To be more specific…even if I could manage to pull off perfect wood removal with perfect cross section symmetry, if I start with too much reflex, will crushing of belly cells not be inevitable at some point on a bow made to be drawn 27-28 inches?  Same issue with the back…at some degree of bend, a self backed bow has got to give, right?  So, is there any way to start out with 7”-9” of reflex and make a 62”-64” bow without severely crushing belly cells and without overstressing the back.  The back issue does not worry me too much , as I can always put a rawhide or sinew backing on it.  The belly crushing is more of a concern. 

I’ve seen a thread about this before, and I seem to remember the consensus being “why take out of a stave what most people try to put into a stave,” and I think the consensus was to work it as is best you can and let whatever set takes place happen.  That’s going to be my plan at this point, but I just wanted to see if anyone has had personal experience with severely, overly reflexed staves and advice about the best way to proceed with it.
Attempting a bow such as this is best done after making many successful bows before hand.With your paticular stave assuming the wood is dry I would reduce any reflex that's in the inner limbs.From the fades and at least a couple inchs on out.To the point of being flat or even slightly deflexed.Leave a good width on the inner limbs also.I do this with a heat gun and a form.
This is assuming the ever increasing reflex on both limbs to the tips is balanced midlimb on out and that the bow tips are aligned good.If not balance and aling that.Get it to brace as soon as possible while "not" needing to pull the tips to bracing position of 6" with long string over 50#'s of pull.You will have enough bow yet then for your projected draw weight.Let it set braced a good hour or so.Pull it a little to check the tiller.Balance that as soon as possible and then pull to your projected draw weight.
Balancing the limbs helps for an even amount of wood taken off from each limb to attain good tiller.It's almost impossible to start with a completely perfect piece of wood.You want an ever increasing reflex midlimb on out.
On bows like this it needs to go slowly tillering as there will be a lot of upfront draw weight.A little removal will mean a lot.Saving the integrity of the limbs is crucial.If it takes 2 afternoons of tillering so be it.Check set often.I use a primitive stringer.Remove stiff spots.Excercize enough to your draw weight to reveal tiller.Creep out to your draw weight 1 inch at a time.
Some set will occur most times.Keeping that reduced after resting to under 1" will be satisfactory for an outstanding performing bow.
On that length of bow starting out with 4 to 5 inches of reflex after reducing reflex on inner limbs and with an 8" handle and fades would be recommended.
Ending up with 3 to 4 inches after tillering will be satisfactory for a great performing bow.
Not having the stave in my hands or even pictures of it limits my advice as I'm not going to assume anything on the side view profile of your stave or the condition of it.This is the best advice I can give you with the circumstances being what that are.
There are things you will learn with this stave if you hav'nt tillered 1 like this before.Failure does'nt mean future success in making wooden bows.Hurdles that with persistence you "can" overcome to future bows to attain a very good performing bow.Some mentioned here.I am blessed with living in osage country.The statement that all self bows holding 4" of reflex or more at approximately that length after tillering are sluggish bows is false and in the same breath all woods are not the same is true.

Title: Re: How much natural reflex…
Post by: txdm on February 27, 2022, 04:29:39 pm
In my experience, 3-4 inches of "baked in" reflex compensates for 1.) the springback from heat treating, and 2.) the set from my poor tillering,  ;D
Title: Re: How much natural reflex…
Post by: ssrhythm on February 28, 2022, 12:05:49 pm
I thought I replied yesterday.  I’ll post pics of this stage tonight.  Why do I reach for such staves when I have three roughed out, relatively straight forward staves begging to be bows?!  I took the stave down a ring yesterday and started really getting into and around the knot.  It’s not as straightforward as I thought it would be.  I’ll have to glue more wood to handle section and steam out some excess reflex at fades.  Thinking from replies I should turn this into a reflex/reflex design, so I’m going to table it until I get these other bows finished up.  Thanks for the replies.
Title: Re: How much natural reflex…
Post by: BowEd on March 01, 2022, 09:11:45 am
For me it was kind of a gradual process making bows more difficult.Then making them out of different kinds of wood too.High highs and low lows come along the way.With difficult bows many times I take the bow in with me overnight and examine it good before proceeding to tiller.It helps a person slow down.Many solutions to problems over time.It's good for me to never rush to a conclusion of a problem unless it's obvious.
Look forward to how she turns out.
Title: Re: How much natural reflex…
Post by: txdm on March 01, 2022, 11:21:59 am
BowEd, in your experience, is it better to add reflex only to the outer half of the limbs, keeping the inner halves flat, than to reflex the whole length of the bow in a "reverse-brace" shape?
Title: Re: How much natural reflex…
Post by: rps3 on March 01, 2022, 02:57:37 pm
I just finished a bow that had a good bit of natural reflex...6-7 inches. The first picture is after I took some of the reflex out already, without adding deflex. I thought it might be too much, so here is what I did. The bow turned out really well and shoots like a dream, while still holding most of its reflex.
(https://i.imgur.com/YQz8BkB.png)
(https://i.imgur.com/wCIrOsJ.png)
(https://i.imgur.com/0mxalEk.png)
Title: Re: How much natural reflex…
Post by: txdm on March 01, 2022, 04:20:57 pm
The bow turned out really well and shoots like a dream, while still holding most of its reflex.

Very nice! Did you use a heat gun to change the reflex? If it's done, please make a full thread about it. Looks like a snappy shooter.
Title: Re: How much natural reflex…
Post by: BowEd on March 01, 2022, 05:57:57 pm
BowEd, in your experience, is it better to add reflex only to the outer half of the limbs, keeping the inner halves flat, than to reflex the whole length of the bow in a "reverse-brace" shape?
I do it both ways.Most times I put an ever increasing reflex to the tip around 2" out from the fades.I have a half form that I do that with 1 limb at a time with dry heat.Most times then I heat treat the belly too.
I've gone to a pegboard many times getting limbs to bend the same before bracing.
That form will give a healthy 5" to 6" of reflex on a 66" bow.A little less on shorter bows.Some staves I do will have a natural deflex in the handle both ways of 1/2" measured midlimb to midlimb.I like taking advantage of those type of staves too.I leave the deflex 2" out from the fades and reflex it like stated before.
After that I will reverse brace it if I want to sinew it to more reflex. Reverse bracing does'nt put too much reflex on the inner limbs if your limbs are tapered properly.
I should add though a D/R bow will be tillered differently than an all reflex bow.You don't want to tiller out the punch of the reflex in a D/R bow.Keep the outer limbs stiff out there at full draw.
rps...Nice looking solution.I'm sure it shoots very good.Those pictures should help out the poster of this thread.
Title: Re: How much natural reflex…
Post by: rps3 on March 01, 2022, 10:01:51 pm
Thanks BowEd. I'll post some pictures soon on another thread. txdm, I did use a heat gun.
Title: Re: How much natural reflex…
Post by: ssrhythm on March 02, 2022, 01:30:53 am
I like that!  Looks great and will probably be what I do when I get back to it. 

My first bow was a character bow with a giant hole in the upper limb and I learned a ton from that experience till I broke it after adding recurves after it shot beautifully as a longbow.  My knot hole work was a little too aggressive on that one, and my violation there could not handle the curves.  Regardless, I like a challenge about as much as I like finishing a good bow. 

That said,  even my best staves are only “relatively straight-forward.”  I think all Osage I’ve seen is a “character stave” to some degree.  Anyhoo, I decided to make some progress on a couple of my roughed out easier staves today, because I’ve got two friends I want to get bows to this summer in addition to the 2022 bow trade bow I need to get built.  I’ll get back to the knotty reflex beast after Oct 15th.
Title: Re: How much natural reflex…
Post by: Kidder on March 02, 2022, 02:48:39 am
BowEd, in your experience, is it better to add reflex only to the outer half of the limbs, keeping the inner halves flat, than to reflex the whole length of the bow in a "reverse-brace" shape?

FLNTKNP17 and I were discussing the location of reflex the other day in the context of Perry reflexed bamboo backed bows and I believe we both came to the conclusion that we get better performance when the reflex is greatest in the inner limbs. I believe this to be because we leave the tips stiff and the highest working portion of the limb is benefiting from the Perry reflex. My experience (a dozen or so BBOs) is far less than Matt’s but we both had the same conclusion. Maybe it’s different with a self bow but I can’t imagine at this late hour bow that would be so.
Title: Re: How much natural reflex…
Post by: BowEd on March 02, 2022, 09:36:53 am
BowEd, in your experience, is it better to add reflex only to the outer half of the limbs, keeping the inner halves flat, than to reflex the whole length of the bow in a "reverse-brace" shape?

FLNTKNP17 and I were discussing the location of reflex the other day in the context of Perry reflexed bamboo backed bows and I believe we both came to the conclusion that we get better performance when the reflex is greatest in the inner limbs. I believe this to be because we leave the tips stiff and the highest working portion of the limb is benefiting from the Perry reflex. My experience (a dozen or so BBOs) is far less than Matt’s but we both had the same conclusion. Maybe it’s different with a self bow but I can’t imagine at this late hour bow that would be so.
The inner limbs do work this is true.Less reflex there makes for less stress and less set if you leave the inner limbs wide enough on self bows.I've made many D/R BBO's myself.All a lot narrower bows than self bows.
There's a number of ways to have reflex on a finished bow without sinew.Heat/natural/or a glue line from the backing.Of them a glue line from a backing would be my stoutest choice.Probably heat next especially on natural and heat treatment.
Keeping reflex on bows means putting the odds in your favor and knowing the design.
Pound for pound mass weight wise sinew takes the less set if it is put on properly and made to work more to do it's job.That means more reflex.
I like that!  Looks great and will probably be what I do when I get back to it. 

My first bow was a character bow with a giant hole in the upper limb and I learned a ton from that experience till I broke it after adding recurves after it shot beautifully as a longbow.  My knot hole work was a little too aggressive on that one, and my violation there could not handle the curves.  Regardless, I like a challenge about as much as I like finishing a good bow. 

That said,  even my best staves are only “relatively straight-forward.”  I think all Osage I’ve seen is a “character stave” to some degree.  Anyhoo, I decided to make some progress on a couple of my roughed out easier staves today, because I’ve got two friends I want to get bows to this summer in addition to the 2022 bow trade bow I need to get built.  I’ll get back to the knotty reflex beast after Oct 15th.
You'll have to make the judgement on that stave with the knots.If they are sound/not on the edge it's good.The more character can mean the less extreme the design too.