Primitive Archer

Main Discussion Area => Bows => Topic started by: Ryan Jacob on December 02, 2017, 04:29:27 am

Title: Did I do something right?
Post by: Ryan Jacob on December 02, 2017, 04:29:27 am
So I split out a stave for the most knot free and straight back. It did however have a weird crown caused by differences in thickness of the crown. I cut of the excess to flatten it a bit. I would chase the ring underneath but I’ll lose 1/2 an inch in the process. Also I’m not that good at it. The removal is highlighted in red. Will I have to back it? I already have some yucca processed for it if needed.
(https://i.imgur.com/tjVcYqk.jpg)
Title: Re: Did I do something right?
Post by: Stick Bender on December 02, 2017, 04:42:26 am
What wood is it ?
Title: Re: Did I do something right?
Post by: Ryan Jacob on December 02, 2017, 06:48:50 am
Stick Bender
Tamarind. I can’t seem to find anyone who uses it other than for risers on a f@#$! glass bow. I know it’s supposed to be good in tension.
Title: Re: Did I do something right?
Post by: Stick Bender on December 02, 2017, 07:50:33 am
I don't know that wood but even on osage if I find some abnormalitys in my chosen ring I go to the next one down figuring nature knows better then me !
Title: Re: Did I do something right?
Post by: Eric Krewson on December 02, 2017, 07:57:30 am
I do like you did on occasion, I like neat backs if possible. I have used mostly osage and as long as a ring is chased properly the rest doesn't matter.
Title: Re: Did I do something right?
Post by: Ryan Jacob on December 02, 2017, 09:03:09 am
The thing is, that part removed was from the same ring as the surface. I essentially thinned the ring in one spot. I don’t know if this changes things.
Title: Re: Did I do something right?
Post by: DC on December 02, 2017, 11:12:10 am
My first rule is "don't touch the back". It doesn't matter if the the back is all lumpy and bumpy just leave it alone. That said if you didn't go all the way through the ring you may be OK. In answer to your question though, I would say "no". Sorry, maybe a backing would be in order.
Title: Re: Did I do something right?
Post by: George Tsoukalas on December 02, 2017, 01:00:24 pm
I agree with DC. In fact, there is no need to decrown a stave which is essentially what you did.
Decrownning us an art. The lateral fibers have to be  violated equally across the back.

When faced with a heavily crowned stave I leave it a few inches longer.

I would back it.

Jawge
Title: Re: Did I do something right?
Post by: Ryan Jacob on December 02, 2017, 06:28:38 pm
I have some yucca processed for it already. I’m guessing 1 or 1.5 layers is enough?
Title: Re: Did I do something right?
Post by: joachimM on December 03, 2017, 02:41:00 am
Should be enough to protect the back.
Wonder what half a layer looks like. Sounds like digging half a hole  >:D
Title: Re: Did I do something right?
Post by: willie on December 03, 2017, 03:01:43 am
the tamarind I looked up is Tamarindus indica. it is classified as  Diffuse-porous; medium to large pores in no specific arrangement.
chasing a ring is recommended on trees that are classified as ring porous, where there is a distinct layer of porous wood that does not do well as the back of the bow. I would try it unbacked and see, especially if your piece is as described above. If it is what you often have to work with, you will never know unless you try to tiller it unbacked . often, Diffuse-porous woods are very difficult to chase a ring on because they do not have much of a "ring" to chase.
Of course, if your goal is to make this stave into a bow and be done with tamarind, then the extra nsurance of a backing is OK
Title: Re: Did I do something right?
Post by: Ryan Jacob on December 04, 2017, 04:09:01 am
JoachimM
I mean full coverage then one only on the center
Willie
I would like the bow to survive but I might try unbacked. If it does fail, then I’ll be cutting some black palm.
Title: Re: Did I do something right?
Post by: willie on December 04, 2017, 08:42:42 am
you could see how snappy the wood acts by shooting it a while (unbacked),before you tiller it out all the way.
Backing could actually make the bow more sluggish if not needed. a lot of what we learn is about the limits of our materiels.
Title: Re: Did I do something right?
Post by: DesertDisciple on December 06, 2017, 10:37:09 am
Did the crown follow the full length of the stave?
If so, then your bow layout will determine how much runoff and where. If the stave is wide enough, put your center line on the correction and treat it like a de-crowned stave. If not then probably back it.

If it were me, I would plan on backing it.

Can we see a picture of the stave?
Title: Re: Did I do something right?
Post by: Ryan Jacob on December 07, 2017, 03:16:33 am
Desert Disciple
Soon but I don’t know if they will be much help