Author Topic: Ocean spray question (pics added)  (Read 6047 times)

0 Members and 1 Guest are viewing this topic.

Offline wizardgoat

  • Member
  • Posts: 2,397
Ocean spray question (pics added)
« on: April 11, 2015, 01:52:44 am »
Been messing around lots with ocean spray,  3 OS bows so far.
On all the bows so far, Ive been getting weird little belly "cracks".
They're not actual cracks, they're there even before the bow starts bending.
They're always where a branch or twig is/was coming in from the side, also on little side knots, almost seems like there's some kind of ripple effect through the wood. It's only 1" diam
I know what a compression fracture looks like, and these are not them.
Like when you scrape over them, your scraper skips a little, and theyre tough to sand smooth
Anyone have any experiences like this? I'll be shooting lots of arrows out of it regardless.
I'll post pics tommorow
« Last Edit: April 14, 2015, 04:51:47 pm by wizardgoat »

Offline Tree_Ninja

  • Member
  • Posts: 181
  • Clandestine Bow-ops
Re: Ocean spray question
« Reply #1 on: April 11, 2015, 12:48:20 pm »
Ive had them. They are annoying, and causes the draw knife to skip or  dig deeper.  Gotta rasp em and carefully sand. Using the finger-feel method of tillering on OS isn't always the way to go.  (IMO)

 I think they may be from the pith that forms on the smaller side branches, or the tangent rays/vascular bundles that are feeding the little side branches.

I worry about hinges near them. 

I also discovered that OS sinks in fresh and salt water, even when fully cured. Not many woods in Canada with a SG over 1.0.

Offline DC

  • Member
  • Posts: 10,396
Re: Ocean spray question
« Reply #2 on: April 11, 2015, 12:58:57 pm »
I've had them too. I've always assumed it was me bouncing my scraper or something. Because I've done mostly OS (10 out of 15)I've assumed wood was just that way. I made a sanding stick with a piece of an 80 grit belt that I use to work them out. I pencil the area dark and then sand until the pencil mark is gone, Then continue scraping. I've never noticed that they were always by a knot but that makes sense. Probably just a little bend in the grain.

Offline wizardgoat

  • Member
  • Posts: 2,397
Re: Ocean spray question
« Reply #3 on: April 11, 2015, 02:30:50 pm »
Thanks for your input guys. This bows all finished, so I don't want to sand it.
I'm not worried about hinges on this one, I'll shoot the snot out of it to be sure.

Offline JonW

  • Member
  • Posts: 1,906
Re: Ocean spray question
« Reply #4 on: April 11, 2015, 03:44:12 pm »
Sorry about changing direction guys but I was wondering to what degree the bark can stay on or if it needs to be completely removed?

Offline DC

  • Member
  • Posts: 10,396
Re: Ocean spray question
« Reply #5 on: April 11, 2015, 09:02:25 pm »
You can try to leave it on, I've had mixed success. A lot better bowyers than I have said that it's not if but when the bark will pop off. I think it depends on how much you bend it. If you make an 80" bow with a 24" draw length, the bark will probably stay on. :-\

Offline JonW

  • Member
  • Posts: 1,906
Re: Ocean spray question
« Reply #6 on: April 11, 2015, 09:29:12 pm »
Well if you know anything about me they will BEND :D I really like the wood so far.

Offline wizardgoat

  • Member
  • Posts: 2,397
Re: Ocean spray question
« Reply #7 on: April 12, 2015, 12:17:26 am »
Happy your liking the wood Jon, I forget when I cut your wood, but I'm 99% sure it was not the winter. Your bark will pop off as soon as you start bending it

Offline PEARL DRUMS

  • Member
  • Posts: 14,079
  • }}}--CK-->
Re: Ocean spray question
« Reply #8 on: April 12, 2015, 08:13:32 am »
Ive only worked one OS bow, it had what your talking about. I used a sanding block and 50 grit to take the last pounds off so I would tear anymore out. Worked just dandy.

Jon my bark was looking just sweet!................right up to low brace. I pulled it 10-12" and CRACK! Ended up spending a good hour scraping it all off. Glad I did, now.
Only when the last tree has died and the last river has been poisoned and the last fish has been caught will we realize we cannot eat money.

Offline wizardgoat

  • Member
  • Posts: 2,397
Re: Ocean spray question
« Reply #9 on: April 14, 2015, 04:32:19 pm »
here a couple photos. the pin knot/cracks really showed up after the stain job and finish, arghhhhh
some of these photos are of the same knot, just a different angle, tried to get as close as i could.
bow is rawhide backed now
















Offline steve b.

  • Member
  • Posts: 999
Re: Ocean spray question (pics added)
« Reply #10 on: April 14, 2015, 06:42:04 pm »
Its a little tough to tell what is back, what is belly, and whether the belly is rounded slightly.  Because you might have a couple things going on there.  I haven't seen a pin on the belly that was an issue unless it is running across the grain and out the side of the bow.  Those will often crack when heated or when the bow is eventually bent.
Often there will be a couple of pins that are spaced just far enough apart that a crack will develop between them.  Depending on where those pins are it will be a show stopper for me.
The bottom line is that pins are a weakness, period.  The question is, whether they are ideally located so not being over stressed. 
Pins on the back or belly will often crack when the bow is heat bent either reflex or deflex, the heat basically is speeding up the inevitable.  But depending on the situation it might not be a big deal or sinew or superglue take care of it no problem.  I've had splinters lift at the pins on the back and so I always back any decrowned bow and some crowned bows depending on how clean.
You have to consider how deep a particular pin is and what direction, because you have to assume any crack that you can see eminating from it could be running the depth of the pin.

No one is going to know whether such and such crack is going to be a problem for that bow so I always assume the worse and over build, slightly.  I don't finish the bow with a crack and I mark and watch it over time as I shoot it, then make a judgement.
I'm not sure what the results are of rounding the belly but my instinct is to flatten, at least.  The bow I'm working right now is getting a concave belly, matching the crown.



Offline wizardgoat

  • Member
  • Posts: 2,397
Re: Ocean spray question (pics added)
« Reply #11 on: April 14, 2015, 07:00:50 pm »
Steve, these are all belly shots and some belly side shots. Back is rawhide.
It's pretty flat belly, rounded corners.  In a PM I mentioned I looked at them through a magnifying glass, and the cracks follow a little pith and disrupts the grain. Hmmmmm
I'll just keep shooting it!
Just curious. How many OS bows have you broke and why do you think?

Offline Carson (CMB)

  • Member
  • Posts: 2,319
Re: Ocean spray question (pics added)
« Reply #12 on: April 14, 2015, 07:52:28 pm »
Steve, you making a Hollow limb bow?! Cant wait to see it.

Wizardgoat, I have had that same type of crack develop on an OS bow. I dint get out the magnifyling glass, and inspect it, but just assumed it was bad and did a patch with horn.
Looking back, I might just let it be and see how it handles over time if I did it again.
"The bow is the old first lyre,
the mono chord, the initial rune of fine art
The humanities grew out from archery as a flower from a seed
No sooner did the soft, sweet note of the bow-string charm the ear of genius than music was born, and from music came poetry and painting and..." Maurice Thompso

Offline steve b.

  • Member
  • Posts: 999
Re: Ocean spray question (pics added)
« Reply #13 on: April 14, 2015, 09:39:05 pm »
WG, again, I don't want to sound like I have all this experience with OS or anything else, other than I've spent the last six months working diligently with OS in everyway and before that I made a half dozen bows, some being kid bows.  I abandoned my OS longbow tradebow because of pin knots simply because I  don't want to take any chances.  I laterally wrapped those pins in 5 different places, with sinew, and I have no fear that the bow will never break.
I've never broke an actual bow that I felt was safe.  I've never broke an OS bow or stave.  I've only done some extreme bending tests, with billet type material, where splinters lifted in tension or extreme heat or quick drying caused pin knots to open or grain cracks to open.  I fill them with superglue and ignore them, normally, or I laminate over them or back the bow or whatever.  The only actual bow that I've I had a problem with was a rawhide backed OS longbow that lifted a splinter at a pin when the rawhide popped off in that exact spot.  I would have had no problem laying that splinter down and rebacking it but instead I threw it in the fire.
I have a takedown molle OS bow that is decrowned and rawhide backed and it takes quite a bend and has been shot quite a bit and has no prolbems despite the pins.

But my point about the pins being weakness is that my bending test showed that cracks USUALLY develop at the pins first, sometimes quickly, long before the roughed up wood that is under tension begins to lift a splinter.  And during the bending or, later, during the shooting, pins that are close enough together will share a crack.   IF you try to  work down through that crack you'll see it can go deep or that it will reappear during subsquent shooting. 
The bottom line is that the pins are a weakness, just like any defect or knot or bug damage or rot is a weakness in any wood.  I welcome that as it just makes the challenge to develop a successful bow even greater.

But as Carson said, in retrospect I might just let some of those defects alone and pretend they don't exist.  For me it depends on the stress level in that area of the limb or whether I'm going to be 5 miles back in a wilderness on a the trip of a lifetime elk hunt.
So the bottom line is, I don't know.  I'm just sharing my experience and thoughts.  Its hard to argue with someone who has a violated bow that has shot 2000 arrows without issue.  I'd rather not consider that the norm and instead  go with the obvious--that pins break open in tension quicker than the wood, and then deal with them accordingly.

The defects in your pics are not as familiar to me.  I'm a little concerned about the fish/football shaped ones.  I can't really tell what is going on there. 
We all need to break a few OS bows to really know.

Offline steve b.

  • Member
  • Posts: 999
Re: Ocean spray question (pics added)
« Reply #14 on: April 14, 2015, 09:49:55 pm »
CMB,
Technically not really a hollow limb but just following the crown on the belly--concave.  I did it with a rhody bow recently and liked it.  Just makes sense.  You end up with a lot more square footage of belly that way and, if you do it right, more even stresses across the limb, IMO.  I'm in the the embryonic stages of experiment.  But when I see where the stresses develop on high crown, flat bellies, I feel like dishing out the belly might be better. 
But unless you use an electric router, god help you if you try to dish out a seasoned OS stave--do it when it is green.