Author Topic: Grain fissures and growth rings...  (Read 2020 times)

0 Members and 1 Guest are viewing this topic.

Offline Hector

  • Member
  • Posts: 6
Grain fissures and growth rings...
« on: October 18, 2013, 03:58:11 pm »
Hello,

Wonder if anyone has covered this so not sure where to post...

The back of a stave I'm working is full of fissures, I stripped the bark and cambium off in the summer, which worked really well and put a few thin diluted layers of pva to stop checking. So far back is intact and its just about to take "A" form so I can begin the tapers. The grain and texture has been left and it looks great, but, firstly, if I come to final tiller and finish I can see a problem with the glue layer cracking and looking terrible (sinew is shockingly expensive so thats out the window unless I can track down enough bulk supply, and its a longbow so pointless really..) , which leads to another point...

...should I flatten the back, just removing to the deepest fissure valley (the fissures form perfect runs of hills and valleys) or just leave the back as is and see what happens? The main thing is that as I understand it the back should be a single unbroken ring and if I take off the high area of the "hills" am I therefore cutting through that ring? Its also fairly hard to see how much total outer ring depth I have underneath the hill/valley section due to ring density and that its still green. And with about 9" of setback I can also envision the fissures just popping - they are longitudinal but there is some runoff, they're oriented to about 5-10 degrees from parallel...

thats about it for now, thanks for reading any input much appreciated,

H

Offline dbb

  • Member
  • Posts: 745
Re: Grain fissures and growth rings...
« Reply #1 on: October 18, 2013, 04:23:08 pm »
I Think knowing what wood you are working on is essential information for getting a good answer.
It's better to ask and look like a fool than not to ask and remain one...

Offline TacticalFate

  • Member
  • Posts: 234
Re: Grain fissures and growth rings...
« Reply #2 on: October 18, 2013, 04:28:24 pm »
Pics would help. Also knowing the type of wood, but generally, you shouldn't have a problem with a bumpy back. If you cut through the hills, your bow will likely have a high chance of failure.

Also PVA glues (like elmers) are relatively soft even when dry, so you shouldn't have any problems with the glue cracking. Also, since PVA glues are water-soulable, when you think the stave is dry enough so that the back wont check, you can leave a damp towel on the back of the stave overnight and you should be able to simply wipe off the re-hydrated glue the next morning. (might have to let the stave dry out for another few days after that)

Offline George Tsoukalas

  • Member
  • Posts: 9,425
    • Traditional and Primitive Archers
Re: Grain fissures and growth rings...
« Reply #3 on: October 18, 2013, 05:37:18 pm »
I think I know what you are talking about. Some woods like hickory have those and you leave them. Don't take them out. Please shot pics so I can tell for sure we are talking about the same thing. Jawge
Set Happens!
If you ain't breakin' you ain't makin!

Offline Joec123able

  • Member
  • Posts: 1,769
Re: Grain fissures and growth rings...
« Reply #4 on: October 18, 2013, 05:48:12 pm »
Are you talking about the little bumps on the back like these ?

I like osage

Offline Hector

  • Member
  • Posts: 6
Re: Grain fissures and growth rings...
« Reply #5 on: November 11, 2013, 04:57:11 pm »
Hello everyone who replied, sorry for the delay
this is probably dead now but anyway...

Joec123able: imagine if that were as your stave there, would be less bother to work on thats for sure!

George Tsoukalas: The wood in question is late summer cut shade grown hornbeam, slight twist and reflex but fine otherwise, the fissures are between 1 - 3 mm deep/wide so not much room for error if I do finally remove, but I really dont want to as its pristine at the moment and I would like to see how they hold up to tiller. Will try to remember photos when I approach the stave again. Its basically roughed out blank now, but still quite green..

TacticalFate: Will bear in mind the glue softening advice..

dbb: still green carpinus betulis, bloody hard, dense, interlocking grain -

For the moment while its curing I'm only using axe, very sharp, or the very used/weathered blades of 2 drawknives, a very sharp spokeshave set fine, and a coarse shinto rasp (this seems to deal with the "furring" that rasping green wood causes). The sharp blades tear if they are not honed really well and stropped, the axe is very good with the grain but will tear knots deeply if you dont consider the flow of it which can be really hard on the eye to ascertain, the "well used/weathered" drawknife works smoothly and semi wedge-like but only along where grain is "less interlocked" so to speak.

Speaking of tough wood - has anyone worked shade grown hawthorn? the "stave" i have is almost iron-like, nothing but a rasp will touch it :-/ its pitched and blunted all the tools I have used on it so far..

Thanks for reading and replying

H

Offline Joec123able

  • Member
  • Posts: 1,769
Re: Grain fissures and growth rings...
« Reply #6 on: November 11, 2013, 06:01:02 pm »
I'm not sure what you mean hector
I like osage