Primitive Archer
Main Discussion Area => Bows => Topic started by: DC on March 29, 2017, 01:34:16 pm
-
Have any of you OS types ever tried wrapping the handle section to keep it from checking? I tried hose clamps but I had to keep going back to tighten them as the wood dried. I decided to try rubber strips. You can build up tremendous pressure with lots of wraps. This stave has been wrapped and drying for 8 months and has a minor check that I can live with. I did a half dozen or so staves and this one is about average. Some have no checking. I'm hoping someone else has tried this so I can get the long term results. I'm concerned that the stresses are just building up in there and someday it will pop open. I'm going to leave them as long as I can just to be safe.
-
DC, I have noticed OC cut at an angle cracks more than one cut flat. this is form cutting and drying full staves, not ruffing them out. It makes me wonder if when you ruff one out if you cut the fades long and square them off and seal them to be rounded out at a later date might help. Good Luck! ED
-
No. But yours is fully dry and not moving, along time ago. I'd unwrap it, deal with the checking, and have that thing flinging arrows in a week or so (SH).
I think you're approach is good and your patience it commended, and I'm sure you know that the rubber is forcing the handle to move moisture toward the limbs or handle, vs. letting it dry more evenly. I'd be interested to see the same drying happen with two coats of wood glue instead of the rubber.
I'm watching your work because I'm intrigued with OS and there are not many using it.
-
Steve -The reason I'm concerned is that I've had some staves that opened like a clam, I'm sure you've seen that. After a year of drying I filled the check with a wedge of walnut. It stayed for a few months and then we had a cold dry spell. It split between the Walnut and the OS. I think you posted one like that about a year back or maybe that was Plum.
Just to make sure we're on the same wavelength the rubber isn't to seal the wood, I use a couple of coats of shellac for that. The rubber is there to mechanically keep the wood from opening up.
OS is renowned for checking. Now that I cut the limbs to the pith(your idea) and seal the ends I have no problems with checking except for the handles. I've had a 1 1/2" handle open up a crack 1/2" across. If I can figure a way around that it will make for a lot nicer OS bow.
-
Yea they open up. But like Ed says some checking occurs at the taper and so the rubber might act double to help stop that. I was intrigued by your clamp idea too.
I had to think back to how I've dealt with stiff handles and I realized that I've only ever done one stiff handle after the handle did the clam thing. I flattened the handle glued on a hunk of hardwood. But I flattened too much and the handle popped off. Shoots just fine without the handle. :OK
Usually the staves are not long enough for a stiff handle, so all I've ever done was use electrical conduit section to glue in billets. I did one molle with a take down handle using two especially wide pieces of OS. I've also filled the clam with epoxy and wrap with leather, and I've done some bendy handles. So, never pursued the checkless stiff handle yet.
I know others have and I think the consensus is to seal the whole stave up really well, for like a year. So I don't know what forces you may be dealing with to allow the limbs to dry faster than the handle.
If you had a stave long enough, and were willing to do a lam handle, you could flatten, kerf, and seal the handle right from the get go and you'd probably get minimum clam effect. Then when it stops moving fill any voids and glue on a handle. Otherwise I think you are on the right track with your rubber and clamps, except that I would remove the bark asap.
And its not so much getting to the pith as it is just reducing the stave so it can dry evenly.
Its amazing stuff. I have a concave belly stave that the string wouldn't align so I abandon it last year. It was at floor tiller or better. Recently I wanted to test the tension strength with the concave belly so I bent one limb over my knee. It went to 45* and took alot to get it to finally break. I folded it completely in half and it stayed together. The break looks like a paint brush with a thousand strands of fiber sticking up.
-
DC, I went out and cut a couple pieces last night just to test out my idea. Here are the pic's I put two coats of tb3 on it. I'll keep an eye on them as they dry and report back. Hope you have a great day. Ed
-
Steve- I tried glue on handles and mine popped off too. I'm trying again but this time I'm scratching the surface with 36 grit and not clamping so hard. I'm wondering if the wood densness makes it hard to glue. I don't have too much trouble finding over 66" pieces but I think billets are the way to go because you can find larger dia billets. I do debark but just the part that will show on the finished bow. I do have a few bark on staves kicking around. They are from when I thought the bark would stay on.
Ed- I thought that's what you meant. Do you just seal the end grain? I was going to go get a stave this morning to try that but now that you are maybe not. I've got 20-30 staves in various stages of drying, I don't really need any more.
Maybe comparing methods might be fruitful. I cut them whenever I see a good one. I debark the back with a dullish draw knife and clean it up with some coarse steel wool so it's all shiny. Rough it out on the band saw and shellac the back,handle and tips. Two coats. Then I leave them outside under cover for 6-8 months and then they come into my shop which is heated when I am there. It's somewhat drier than outside. Another few months and then they go into my warm box until their weight stabilises
-
DC, on these pieces I sealed the end cut off and only the short end on the cut off side. not full length say from fade to tip and didn't glue the tip(end) on these as I have them down to the pith. Hope that's a clear as mud. Ed
-
Well an angled cut is a larger surface area for moisture to escape.
I just leave them whole and hope for the best. Some make it others don't. I think 1 yr per inch diameter is key. I have opened up some OS from over a year ago and the inside bark is still green. I had a 5 inch diameter stave split on a knot. I might be able to get two bows if I mount a handle.
Maybe one day I will try some PEG stabilizer on a wet green stave, it is a common laxative that stabilizes the moisture in the wood.
Have you tried a dry heat treatment on a super fresh roughed out stave?
I think best time to harvest is during a summer drought or a cold dry winter day. During the spring before bud emergence there is too much sugar. Harvesting/transplanting anything during flowering is never a great idea, all of the plants resources go to fueling the flower development. Harvesting During the rainy fall and it it is too soaked. Garden by the phases of the moon. You'd be surprised what differences there are between a full moon and a new moon.
Also Ed,
I like the choice of background.
-
Well an angled cut is a larger surface area for moisture to escape.
I just leave them whole and hope for the best. Some make it others don't. I think 1 yr per inch diameter is key. I have opened up some OS from over a year ago and the inside bark is still green. I had a 5 inch diameter stave split on a knot. I might be able to get two bows if I mount a handle.
Maybe one day I will try some PEG stabilizer on a wet green stave, it is a common laxative that stabilizes the moisture in the wood.
Have you tried a dry heat treatment on a super fresh roughed out stave?
Also Ed,
I like the choice of background.
5" Yikes, must have weighed a ton.
How would you apply the PEG?
No, but I have steamed a few and I sort of think that it helped. I've been meaning to steam a whole stave to see what happens but it's just such a long term project. I probably have more staves than I'll ever use.
I noticed Ed's choice of background too ;) ;)
-
I noticed Ed's choice of background too ;) ;)
[/quote]
wet glue, I couldn't put it on the wife's table.LOL >:D O:) Ed
-
Had a thought today DC, what if you opened up the other '3' sides of the handle to expose grain? ends are open in fade, and I know from a stave you gave me that you have opened belly before - have you tried the sides too?
g.
-
Yes, I tried roughing out all 3 sides. I didn't seem to help. I thought it sounded like a good idea too. Dried to fast I guess.
-
Cut in October when the leaves drop, it's cool, and will dry slower. I generally keep them laying on the ground for the first month in my garage....the floor is cement, and cold. I then wait for the first cracks in the ends of the wood, cut those pieces off, and then seal the stave. Ultra slow drying and time of year, are important in my opinion.
-
Sounds like a well thought out method but why wait to seal the ends? If you are after a slow dry anyway why sacrifice a few inches of length? Especially when long OS staves are rare.
I was stacking mine in a corner outside my shop door under cover for the first month or so but I noticed a bit of mildew on a couple. A little too slow maybe.
-
Sounds like a well thought out method but why wait to seal the ends? If you are after a slow dry anyway why sacrifice a few inches of length? Especially when long OS staves are rare.
I was stacking mine in a corner outside my shop door under cover for the first month or so but I noticed a bit of mildew on a couple. A little too slow maybe.
When you say it molded was that bark on , or like shown in the pics above?
-
I tidied up my staves a couple of days ago and now I can't find them. ??? They would have been cut to the pith but some I left the bark on and some I didn't. The mildew was on the belly. It wasn't bad, it was just starting to turn greyish in spots. A little bit better air circulation would have stopped it.
-
I think its just characteristic of OS to check. Partly because it is OS but also because it is dense and yet small diameter. Other good bow woods of similar size check less or not at all. I guess if you are dying for an unchecked rigid handle you could go to great lengths to slow dry the handle, maybe two years or whatever, but I'm not convinced that it is a slow drying issue as it is an "even" drying issue and is different from stave to stave. In my experience I can cut any living OS and have it flinging arrows in 6 weeks or less. I've done it in 4 weeks and the bow took no set. So I just open up the handle during initial tiller and then deal with the handle when the times comes, either lamming it or letting it bend.
If the limbs take no set then the moisture in the handle can't be that big of an issue--whether its drying too fast outside vs. inside, etc. I have roughed brand new OS staves and tried to burn the shavings. They do not burn very well. 24 hours later the same shavings make good kindling. They are drying fast, laying on a concrete floor in an unheated building in the winter of Oregon. So a stave averaging .7" thickness tip to tip is not going to hold alot of moisture if it is 60% RH environment for a week or more.
So the wood itself is nothing special regarding density. Warm it up and it dries like anything else. Initially (the first week only), you have to control the drying so it won't check. After that you can introduce it to normal room temperatures and it will dry without checking.
Here's a pre and post pic of what I'd do with split handles. The lower is bow from last year that I sliced and glued. The handle popped off so you can see the epoxy just filled the void. I think OS needs to be prep'd better for laming or sinewing. Everything pops off easily. You have to degrease and/or rough it up.
The upper pic is a stave I cut a month or so ago. I kerf'd the handle and watch it. The kerf showed signs of increased checking so I put two coats of wood glue on the whole bow, then weighed it. It is at floor tiller and weighed 1 3/4 pounds. Two weeks later it weighed 1 1/2 pounds and continues to NOT lose any weight. This is the initial drying I'm talking about. It is done checking, guaranteed. I will scrape off the glue and introduce it to room temps and in a week or so will make a bow without set.
-
.
-
If you are just talking about the limbs I agree 100%. Handles are something else. I just had a bow that was over a year old with an insert in the handle. I wanted to touch it up to give to a kid at the range. I left it in the shop overnight and the handle split. Another roughed out stave I gave to Shofu was at least 6 months drying and the handle had not split. He took it home to a more humid environment and the handle split in a few days.
-
Again, I'm intrigued, and only guessing here, but you are leaving out a lot of details so its hard to tell. Since you are getting checks in high humidity I'm guessing the handles already possessed stress fractures and the changes in humidy changes caused a little more movement. Otherwise it just doesn't make sense that an otherwise structurally sound component suddenly fractures because of a small change in humidity.
But lets say it is all true. Is it really worth going to such great pains to keep the handles intact vs. just pre-splitting them and doing whatever to make a handle in the end??
-
More and more it isn't. That split just bugs me and unless you use bondo it's quite a bit of work to fill.
-
http://www.primitivearcher.com/smf/index.php/topic,60167.0.html (http://www.primitivearcher.com/smf/index.php/topic,60167.0.html)
Check out Knoll flex handle locust bow - the built up flexible handle might be a good solution for OS staves
g
-
DC, a quick report back on my experiment on this. after I cut those two pieces of OS, I sealed them with glue, the next day I put them in front of the heater and have left them there. as of today, there is no cracking on them. I think I'll need to do this again with full length pieces(some time) out for now. Ed
-
I did one too. I cut it and roughed it out with a squared off handle section. Next day the handle had split down the side.I cut the handle off :(. This one was my fault. I got it all done and put it on the work bench and went in to make supper. Forgot all about it ::) ::). It was really wet.
-
Have any of you OS types ever tried wrapping the handle section to keep it from checking?
Interesting problem and creative approach to finding a solution.
I wish it grew further north so that I could try some.
I wonder if breaking down the problem a bit more would give direction to finding a good remedy.
When purposely splitting OS, green or dry, is it tougher than average or does it split easily? Does it have interlocking grain? or the opposite?
When drying OS, does it seem to shrink more than most, or is it prone to warping and bowing?
-
OS seems to split well but I haven't split that many. When I first started messing with it I split some but they all seemed to split straight so I just bandsaw them all now.
Maybe a little bowing but most dry nice and straight. Well, as straight as they were when I cut them. There's usually a kink or two. I only have Yew, Maple,Dogwood and Crabapple to compare with but I think it must shrink more than most. If it didn't shrink I don't think it would check.
-
DC
Observing that it splits "well" might be a description of whether it splits straight or not. I was hoping to find out if it split easily or was hard to split. I am guessing that in order to split well, it is an easy wood to split.
Put another way, my questions are directed to trying to see if drying OS creates more stress (shrinkage) than most, or whether it just doesn't hold together well with otherwise average stress/shrinkage.
Different woods shrink more or less than others, and in different directions (relative to the grain). These qualities are often discussed in woodworking and furniture making forums. Doubt that you would find OS listed, or whether you could do much different on account of the smaller diameters typically used. Some woods are quite a bit different from others, though, especially when comparing certain directions. Radial and tangential.
What happens if you saw the stave down the middle right thru the handle area, tie back together as sawn, except with some spacers to facilitate drying, then once dry, glue the saw cut back together, remove bark as desired, and shape handle area per design?
-
I think you are on to it willie. I don't think it splits. Not like oak where you hit the end of a six foot log it splits all the way down its length running along the grain. OS splits off to the side, if I remember? It carves like celery when it is wet and you can have a fresh cut stave debarked and floor tillered in an hour or two.
Like I said, I think its just characteristic for it to behave the way it does when drying. You can put alot of effort into drying it and the handle may or may not split anyway.
If anything I'm most intrigued by the idea of tightly wrapping or clamping the handle as well as sealing it for best results.
I've seen little reaction-wood-type movement from OS when it is split. I've never seen it twist or warp. It doesn't shrink noticeably but obviously it is to some degree. I've only seen a reflex or deflex half move in one direction or another (more or less deflex/reflex) slightly.
I don't think it heat treats well. It will heat bend ok but I don't think it keeps the shape under strain. Its almost hard to get it to burn.
-
DC
What happens if you saw the stave down the middle right thru the handle area, tie back together as sawn, except with some spacers to facilitate drying, then once dry, glue the saw cut back together, remove bark as desired, and shape handle area per design?
This would take a year and a half to answer, you want to wait ;) I can guess though. I would think you could cut it right through the middle and stand the two pieces in a corner not tied together and after a year they would match up. I don't think it moves around much. What it does is this. This was ripped with a bandsaw. You can see how much it's shrunk, radially I guess. Double that gap and that is the size of the check you would have.
-
DC
nice pic that explains a lot. the crack is radial and excessive possibly because the tangential shrinkage is more than average?
Bruce Hoadley, Understanding Wood has a nice chapter on just these sort of issues, and how to work with them.
It seems that some woods have a large ratio, between the different types of shrinkage....
-
Just for curiosity I figured the SG of OS. The piece I did is 1.04. It's bone dry, been kicking around my workbench for a year or so. I microwaved it just to check and the weight never changed. Every piece of OS I've checked has sunk but this is the first time I did the figuring. So it just barely sinks.
-
I checked my test pieces again, no cracks visible, however the wood has shrunk. you can see it in the bark, it's getting a wrinkle in it. Ed
-
That's a week, right? Have they been in front of a heater the whole time? That's amazing. Can you throw that chunk in a bucket of water to see if it sinks. I just find it strange that others haven't commented on sinking wood.
-
DC, yes for the most part it's been directly in front of a heater. within a couple inches, I was trying to get it to crack. as far as I know OS sinks, but yes I'll toss it in some water when I get home tonight, and let you know tomorrow. Ed
-
That's bizarre. A couple of times I tried to dry pieces like that to make a mallet. I just shellacked the ends and threw them under my workbench. No joy. Maybe glue works better than shellac.
-
I don't know about glue working better than shellac, as I've seen them split with the same glue, tb3. I'm thinking my test pieces were too short and this may affect my test. will need to try it again with a full length stave, I have one that needs cut down. Ed
-
Everything I could find online has Ocean Spray less the 1.0 specific gravity. I tested a piece and it sunk in the bathtub. I also tossed in a piece of lignum vitae which is supposed to be the highest sg wood and a piece of high elevation Douglas fir. The OS sunk like the LV and DF floated of course
-
On another note, I found a whole area filled with 'old growth' ocean spray today. Trees are 4-6" diameter. Thinking maybe that might be one solution: use bigger wood?
g
-
here is pic. I wear size 9 glove
g
-
DC, I dropped that piece in the water last night. It sank like a rock.
-
On another note, I found a whole area filled with 'old growth' ocean spray today. Trees are 4-6" diameter. Thinking maybe that might be one solution: use bigger wood?
g
Wow, I thought I had big OS. If you can split that in half it "should" dry OK. If it's 3" it will make full handles.
-
I just find it strange that others haven't commented on sinking wood.
lol, I guess most of us are a bit envious that you can find some bow wood that dense in your backyard.
some nice sticks there, Shofu
-
I will get you some DC and continue the experiment
g
-
All the oceanspray I have tested sank in fresh water.
You can try salting the water to see of it floats. It is a mysterious fiber and I think it warrants a bunch of testing/experimenting . Especially the heat treating.
-
I threw an off cut in the ocean and it sank. Cheers- Brendan
-
Sorry to steal your thred Don. On Sunday I cut this os. It was about 3 1/2" dia and 77 1/2" long. It was growing about 2 degrees off of horizontal, about a foot off the ground. It split great. Here is the top side of it. 2" wide 1 5/8" thick and 75" long. I think there are two knots, one of which wont end up in the bow. Sealed the ends, left the bark. Let's see what we get. Cheers- Brendan
-
Cool!
-
Seeing some awesome, big pieces of OS on this thread! My experience using larger diameter ocean spray is that it needs to be trapped substantially, or else it can chrysal. IMHO, its so tension strong that the high crown on smaller pieces is actually required for low set and no chrysaling. Had a beautiful clean 2 1/2" diameter (and rather flat-crowned even for that diameter) piece chrysal in both limbs during the final tiller. Don't want anyone else to have to repeat that tragedy! :'(
-
Well, that's kind of disappointing to hear. I was hoping that a flatter back on OS would work into some kind of super bow :D :D What you're saying kind of means there is no point in hunting down large OS. Had you heat treated the belly on the one that chrysalled?
-
Ya, I hoped that too :-\ It could definitely be issues with my tillering (and the high stress design), but the chrysalling was even in both limbs, so I'm not sure. I did heat treat right after floor tiller/recurving, and again later during tillering. I think my issue was that my limbs were very stable thickness, and I trapped at about the same angle for the whole length, which meant that the back:belly ratio was much lower at the tips than towards the handle. Next time I'll trap the inner limbs considerably more.
It was an awesome bow while it lasted though (SH) :-[
(http://i.imgur.com/7oUY9d7.jpg)
-
I was hoping that a flatter back on OS would work into some kind of super bow
you could trap it, so to speak, with a flat full width backing of a not so stiff wood, and avoid the stress concentration on a pin knot.