Primitive Archer

Main Discussion Area => Bows => Topic started by: DC on January 29, 2017, 03:04:30 pm

Title: And some you lose
Post by: DC on January 29, 2017, 03:04:30 pm
This is the OS recurve I've been working on. Managed 14 shots got 165fps on the 13th. You can see the tiny pin where the splinter(s) started. Just about every OS I've broken has started at a little pin. I guess 27 1/2" draw was too much. The bow is 64 NTN but the working limbs are only 18". I'm starting to see a size limitation for OS.
Title: Re: And some you lose
Post by: Stick Bender on January 29, 2017, 03:20:25 pm
Oh man that sucks  !! 
Title: Re: And some you lose
Post by: JW_Halverson on January 29, 2017, 03:24:02 pm
Aw dang!
Title: Re: And some you lose
Post by: bow101 on January 29, 2017, 04:05:56 pm
in my experience a 27 inch working limb seems to do best..  If the working limb is less than,,, you will see more set or string follow.
Title: Re: And some you lose
Post by: Stixnstones on January 29, 2017, 04:24:51 pm
Ouch!
Title: Re: And some you lose
Post by: DC on January 29, 2017, 04:30:07 pm
One thing I did was make the inserts too long. I was afraid to go too thin where the insert was and that shortened the working limb by about two inches. Next time I'll make the insert just as long as the curve.
Title: Re: And some you lose
Post by: Philipp A on January 29, 2017, 04:46:38 pm
Hi DC, was this a heavily crowned stave? Sorry about the break :(
Title: Re: And some you lose
Post by: DC on January 29, 2017, 04:51:31 pm
Yes, the handle is the original size 1 1/2". OS usually handles the high crown although this one didn't. I've made OS bows with smaller pieces but I don't think I worked them this hard.
Title: Re: And some you lose
Post by: Philipp A on January 29, 2017, 05:05:36 pm
I have had trouble with heavily crowned staves in the same area when trying to make a shorter bow that didn't bend through the handle. If I backed them and thinned them out I have ended up in many cases with chrysals.....can't win them all  :)
Title: Re: And some you lose
Post by: willie on January 29, 2017, 05:49:13 pm
Quote
I'm starting to see a size limitation for OS.

Possibly a size limitation on how narrow a crown you can have? Could a decrown (flattening), to a width that is at least half of the belly,  give you some margin and keep the performance?
Title: Re: And some you lose
Post by: Marc St Louis on January 29, 2017, 06:04:39 pm
That is a pain but 18" seems a bit short for a 64" bow.  I can get at lest 25" of working limb from a 64" bow
Title: Re: And some you lose
Post by: penderbender on January 29, 2017, 06:38:11 pm
That's a bummer. Was looking nice Don. Oh well you got a 1000 other potential os staves around you! Cheers - Brendan
Title: Re: And some you lose
Post by: DC on January 29, 2017, 06:44:41 pm
That is a pain but 18" seems a bit short for a 64" bow.  I can get at least 25" of working limb from a 64" bow

I can see how I could stretch it out close to that and that probably would have made the difference. Like I said above I could shorten the insert, tighten up the curves and make my fades a little steeper. The string didn't lift off until full draw so I could shorten the curve an inch. Next time.

Willie- decrowning scares me ;D. OS's rings are very faint and those pins are always in a bit of a rise. I'd be afraid a decrowned back would be asking for trouble. I do seem to have a spare limb I could try it out on though ;). I could decrown it, grab it in the vise and take a big pull on it. I might try that.

Brendan- I've got about 30 staves and assorted billets dry and ready to go. I've had to force myself to not cut any more. I'm almost 70(hate to see that in print), don't want to leave a bunch of wood for my wife to deal with ;D ;D
Title: Re: And some you lose
Post by: BowEd on January 29, 2017, 07:17:23 pm
Sorry to see that.They are heart breakers for sure.Even getting 22" of working limb on each limb would help a bunch on a 64" bow.With something like you've just experienced maybe a little rawhide or sinew might make the difference.
Title: Re: And some you lose
Post by: Bryce on January 29, 2017, 07:26:48 pm
I've got a 60" OS that pulls 28" that still shoot great. Might have been a flaw in the wood who knows. But I think Marc is right.
Title: Re: And some you lose
Post by: DC on January 29, 2017, 07:29:17 pm
I've got a 60" OS that pulls 28" that still shoot great. Might have been a flaw in the wood who knows. But I think Marc is right.

Recurve?
Title: Re: And some you lose
Post by: George Tsoukalas on January 29, 2017, 07:50:15 pm
DC, that bow is pretty heavily crowned; leaving it a few inches longer would have saved it probably.

That's usually what I do with saplings. With a sizable crown the stresses go right down the middle of the back and that is where the break is.

Also, looks like the design you chose stresses the bow quite  a bit

Jawge
Title: Re: And some you lose
Post by: Gorzideudeus on January 29, 2017, 08:04:56 pm
Maybe someday I'll dare to try bends like that!
Title: Re: And some you lose
Post by: DC on January 29, 2017, 08:10:00 pm
I took a shot. One of the problems with Ocean Spray is that an average large piece is 2", a few come bigger, but not many. They also come in limited lengths. They sorta put out new shoots every year so they will grow 5-6'(if you're lucky) and then next year a new side shoot takes over. So you're stuck with a 1 1/2" x 64" stave, average. It limits the design possibilities a bit. But every once in a while you'll get one that you can almost bend the ends together. That throws your judgement off a bit. Once in a while the first section will be less than 4' long but will be almost 3" in diameter. I'm going to start cutting those for billets. The upside, like Brendan said, is that there are hundreds of staves within walking distance of me. I could get up, go get a stave, and be back inside an hour, on foot.
Title: Re: And some you lose
Post by: DC on January 29, 2017, 08:11:41 pm
Maybe someday I'll dare to try bends like that!

I tried a half dozen times with offcuts and I could not get a tight bend in OS. That's why I used the inserts.
Title: Re: And some you lose
Post by: upstatenybowyer on January 29, 2017, 08:18:18 pm
Man sorry to hear about that one. If it's any consolation, I just had a short osage recurve blow up in my face  :o.
Title: Re: And some you lose
Post by: Peacebow_Coos on January 30, 2017, 12:22:20 am
Bummer DC, I've had trouble with bending OS as well, with steam and dry heat.  Sure is tough stuff though, look at that belly still intact, now that's a tension break.  I'm sure your next one will be better
Title: Re: And some you lose
Post by: Pappy on January 30, 2017, 08:41:59 am
That stinks, that was a beauty. :)
 Pappy
Title: Re: And some you lose
Post by: bow101 on January 30, 2017, 12:10:03 pm
This is the OS recurve I've been working on. Managed 14 shots got 165fps on the 13th. You can see the tiny pin where the splinter(s) started. Just about every OS I've broken has started at a little pin. I guess 27 1/2" draw was too much. The bow is 64 NTN but the working limbs are only 18". I'm starting to see a size limitation for OS.

Yep, ya win some ya lose some, I have broke the last 2.  Currently nursing this next one. " but the working limbs are only 18"  I have found from experience that a working limb of 27" or more does not put as much stress on Wooden bows.
This is the problem I have always trying to achieve a good bow that pulls at least 40-42# at 28".  And later after tillering finding out the bow is only 36-38#...  :P
Title: Re: And some you lose
Post by: Aaron H on January 30, 2017, 12:42:17 pm
Bummer, is this the same bow that you had the recurve questions about?
Title: Re: And some you lose
Post by: DC on January 30, 2017, 01:17:29 pm
Yup. It's not all bad. I learned a bunch of stuff from this post. I had messed up a bit on the insert glue line so it wasn't going to be a showpiece anyway. One high point is that I've struggled with string alignment on recurves and this one kept the string on even when it broke. A step in the right direction :) :)
Title: Re: And some you lose
Post by: Springbuck on January 31, 2017, 01:07:35 pm
Ahhh, my condolences.  The good die young, right?
Title: Re: And some you lose
Post by: DC on January 31, 2017, 01:21:23 pm
I think it would have been a lot worse if it broke after 200 shots :D. But if I got 200 shots through it, it probably wouldn't have broke. It doesn't upset me to break a bow. I'm doing this because I like making bows. It doesn't matter what I'm working on. I've got 20 plus bows hanging on the wall behind me. If they didn't break they would just pile up on the floor. I honestly believe that if you pay attention you learn more breaking than making. At least you know you're taking it to the limit.
Title: Re: And some you lose
Post by: burtonridr on January 31, 2017, 01:25:09 pm
Ouch! that was a good lookin bow too.