Updated! Rollercoaster stave: a ride-a-long (take 2). . DONE!! Finished pics:)

[Nim-rod]

In a couple pics it looks like the back has some burning from dry heat and that's a recipe for disaster. The backing looks like regular cotton sheet material which is not very strong and it didn't appear to have much of a bond anyways. Try real linen made from the flax plant as it is super strong stuff but you will have to go to a fabric store and ask for it. I don't think that was the cause of the break but something to consider on future builds.
 I think Osage tree is right...Too Dry hence the clean break without splintering.
 Pretty big challeng for a first bow. Good job though in what you actually did accomplish and I'm sure you learned more on this one bow than you would have on a nice easy stave or board. Keep at it and I look foward to seeing another from you.

[k-hat]

Well now Jawge, I was only at 17"  

Didn't burn the back, i only cook bellies:).  What you may be seeing is some discoloration from crisco that leaked around.  In fact, the part that broke never received any heat   :confused:  

The backing is 100% silk.  Kind of a surprise there, though it was my first time to use silk.  I have some linen ima go back to instead of silk, most likely.

I cut a piece off and examined it.  It's pretty porous all the way through, really sponge-like in appearance.  Perty sure that's the culprit.  Don't know if that's "live tree dry rot or what", but they've had that appearance from the getgo, so all my staves from that tree are likely in the same condition.

I'll probly start another bow Monday   :D

Thanks for all the input and encouragement!

[Nim-rod]

I had to chase rings on ash because it had almost 1/4" of that porous stuff too. THe first attempt snapped right away. I wonder if we are atlaking of the same thing. Kinda like an inner bark that is very hard and porous but looks decent until ya try to bend it. I cut that tree down just as the sap was starting to run and the bark came right off. Wish I knew what that was too.

[Living_waters]

If you look at the cross section you can see the sap wood is dramatically thinner on one side of the stave. That could have contributed to the overstressed back. I broke 2 staves that had irregular sap wood and considered everything from rot to overdraw. But after I sawed some cross sections I believe it was just the reality of a bad choice of wood.    
These are maple and should not have broke on their back like this.  Notice how irregular the back surface is, it is magnified internally. some spots had almost no sap wood.
What ever the reason, your bow has provided a wealth of knowledge. I have always said you learn more from a broken bow then a shooter. Dont give up on the other staves, just figure out how to make them work  

[k-hat]

Well, thanks to all the encouragement, i took a second look at my hackberry stash just before i cut it all up for firewood.  Turns out i think i can salvage a couple of staves if i chase a ring (gonna hafta take about an inch off to get to a decent one).  Hackberry is notoriously not very chase-able, but i've started one and i think we can make it work.  Here's my "draw knife" i'll be working with (half a pair of old shears):

 

Here is the end of the stave i'm working on.  Going after that second thick ring from top:

 

And, just to see what i'm dealing with, here is the back so far.  Top layers are very thin ringed and difficult to see where you are.  Nothing like chasing osage!!

 

Well, wish me luck!  And thanks again for the encouragement.  I'll post progress after i get'r floor tillered.

[PEARL DRUMS]

Your crazy and must have at least twice the energy I do. Good Luck!

[k-hat]

Crazy, or stubborn.  Bout the same sometimes!!

[coaster500]

It's not crazy or stuborn Kevin ... I'm with you when ya fall off get right back on ...  only way I ever learned anything    

That stave looks a bit more user friendly than the first one. If it were mine I would try to get it to bend a bit more even across the whole bow in the beginining not just at the fades.... I am a newby so take anything I say with a grain of salt.

You'll nail it this time!!

[k-hat]

Well, got about 8 inches left to remove of the last ring, but bout got'r chased.  Here are some pics of the back and you can see the butt end a little in one.  I'm stopping short of the ring i was going for, which was about 1/8" thick, this one is between 1/16th at thinnest and 1/8th at thickest, which i suppose is enough.

You may notice some extra material left around three pin knots. toward the top end of the stave.  Gonna fine tune those next.

 

 

 

I'm pretty excited about this one.  This will be my first finished chased ring.  I've started some on a couple of osage staves, but haven't finished those yet, too many distractions  
I will say osage is definitely easier than this was, but this was a good teacher, and finishing those osage staves will be a breeze!!!


As you can see, this one is quite a bit wavier and undulationier (yes, made up another word!) than the one i started with in this thread.  Just what i was hoping for . . . more challenge!

On the downside, this 2+ inch wide stave is now down to about 1.5" wide due to how deep i had to go to get some good wood.  Yes, much narrower than preferred for hackberry, but she will be backed with silk and only going to 30#.  Hope that does the trick.    

Can't wait to finish shaping and floor tiller!!      

Appreciate any thoughts and input!

[k-hat]

After a bunch of shaving and rasping, finally got'r down to about floor tiller.  Her character is really coming out now.  

Only question is, how much character do i wanna leave in her?

I know i've got some straightening to do laterally to get the string through the handle (now about an inch out).  And need to even up the limbs as well.  

Part of me says get her as straight as possible, part says tiller the crazy thing!

Eyeball a straight line tip to tip and you can see the string alignment issues:
 

Another character pic:
 

Compare this one (top) to the bottom pic and you can see that she is a sister stave to the one that started this thread (and broke).  The first one had already been corrected a bit before the first pic taken:
 
 

If i start corrections, you can bet i'll be working on my next stave during the rehydration period   :D

[PEARL DRUMS]

Is that the same width from end to end?

[k-hat]

Right now yes, cept one area that i need to narrow a bit.  Needed to use the belly to help me see where to shave off the edge, didn't get to it yet.  

I wanted to get it to a heat-correctable width and thickness before i take more off.  I'm gonna narrow the tips too, bout the last 8 inches or so.  

Figured it'd be ok to do my corrections before all that?

[PEARL DRUMS]

The stave has to be a bow before it can be floor tillered.

[PEARL DRUMS]

Originally posted by PEARL DRUMS:
The stave has to be a bow before it can be floor tillered.

Let me reprahse that. That sounded rude and wasnt my intention. The stave needs to be cut/rasped out to your desired profile before you take anymore from that belly. Get it shaped, then concern yourself with alignment.

[k-hat]

No worries PD.  Guess I misrepresented my intentions, and maybe a little confused.  The order i was going to go in was:

1. Heat correct the lateral issues
2. Rasp in the width tapers on the last 8 inches of each limb
3.  Belly taper and floor tiller.

But you're saying go in the order of 2, 1, 3?  

I'm still learning the "way of the stave", so all comments and suggestions are welcome.  Don't know any other way to learn (other than trial and error ...but who wants to do that    , and i hope this is helpful to someone else down the road.

Thanks for your input PD.

[PEARL DRUMS]

Most folks get their desired profile done first thing. That dictates your taper.

[PEARL DRUMS]

[k-hat]

That's what i've always done with my board bows, but to be honest, it was difficult for me to see how i needed to lay it out with it as wavy as it was becoming. I used the ring pattern on the belly as i removed material to see where the natural edges of the stave should be, that way i could remove width where it needed to be without forcing an unnatural shape/"violating" the rings on the sides.
I took it down to the max width and limb thickness tip to tip hoping that she would start "speaking to me"       so i could get a better idea how to approach the width profile without doing irreversible damage.

If there's a better way (other than just having the eye of experience to see the way to lay it out from the back), lemme know!  The grain on the back was too fine for my newbie eyes to follow   :rolleyes:  

I did follow your advice and began finishing the width parallels and tapers.  Hope to have that done by the end of the weekend.

[k-hat]

Ok, put'r on the tiller block this morning.  Shot a couple of pics and a video i'm gonna try posting ala coaster500:

At rest, no tension:

 


Drawn to 14" and 15# on somewhat long string:

 


Here is a video link so you can see movement:

 http://s1216.photobucket.com/albums/dd374/k-hat/?action=view¤t=120117_001-1.mp4


Sorry for the quality, gotta get a decent camera, will when funds permit :

Looking forward to your comments:)

[Steve B.]

I think that, if you are going to continue to build bows in the future, its ok to use different approaches and to experiment with your new ideas because you will learn from them and eventually find your own way.  That's actually part of the satisfaction--persevering through your failures and achieving success.  So go with your gut and enjoy.

My thought on allowing the waviness of the rings to dictate the edges of the limbs are that it might work as long as you leave enough wood on for later tiller and design.  I think there would be a temptation to flatten the belly full length in order to see the ring waviness and you might go too far.
The last 6" or so of the limbs need to be rigid when complete.  If you flatten that belly out at full width then later taper edges you might have weak tips, whereas you should have allowed the tips the narrow yet thicken to remain rigid.  
So it depends on your design and such.

Also, with floor tillering at full width, when you taper the edges your floor tiller will change, or could.  

I'm doing an osage bow now with wobble and twist.  I put the stave in a vise, back up, and drew a line, with hand/eye, down the entire crown, following the wobbles in every way.  Then I measured out to the edges from there to lay out the bow.

I can't tell much from the video.  I have another bow with similar looking limbs as yours.  I don't use the tiller setup like you have.  I use a vise and stick.  With the bow in the vise, strung, and belly up, I pull up by hand so I'm close to see the limbs moving.  I look at how much movement I'm getting, percentage-wise, from tip to fade.  Knots, undulations, tips, and handle, will be stiffer but everything else has to move via a certain percentage.
I'll do a little of that then tiller stick and step back and look.  Then I measure each limbs overall arc compared to the other.