Author Topic: Working on a static recurve  (Read 21894 times)

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Offline bubbles

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Re: Working on a static recurve
« Reply #15 on: February 07, 2014, 02:11:51 pm »
That  V-splice looks like a PatM glue up to me! :).  I've been thinking about trying a spliced lam recurve. Good to know there are multiple glue up options.

Offline Easternarcher

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Re: Working on a static recurve
« Reply #16 on: February 07, 2014, 02:23:37 pm »
I use Urac for statics and glueups.
I also like using tip wedges and underlays to prevent the curve from pulling out.
These aren't as drastic as yours tho.

Offline PatM

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Re: Working on a static recurve
« Reply #17 on: February 07, 2014, 04:18:30 pm »
Yeah, that is mine. don't mind at all. I added an underlay to hide the v-splice. Not sure why you would have trouble with that type of splice. You seem to have access to far more precision equipment than I have.
 I think it is best to have the backing go right to the tip rather than feathering out on the curve. You want to support that grain on the tips. It looks like it should have run more in the direction of the angle rather than across it.
 I'll link to some pics on PP that show a similar joint to the one you made except the tip is tapered to an edge that the loop straddles rather than resting in a groove. I think that's a lighter tip solution.
http://paleoplanet69529.yuku.com/reply/256834/NorthEurasian-laminated-bow#reply-256834

 Here's a close up of the tip with the underlay: Keep in mind my spliced in tips are steam bent so the wood is  curved rather than just cut to shape.


« Last Edit: February 07, 2014, 04:43:27 pm by PatM »

Offline adb

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Re: Working on a static recurve
« Reply #18 on: February 07, 2014, 05:18:56 pm »
Thanks, PatM. Thought that was yours. So, are you going to answer the question? How did you get the inside surfaces of the V splice smooth enough for glue up?  ???

Interesting write up on PP. Shows there's more than one way to skin a cat. I wondered about running the backing right up to the tip, but I thought it would be unnecessary.

Anyway... some progress. Roughed in some pin nocks, cut some shallow string grooves on the back of the static tips, and narrowed the tips down further to 1/2". I'm still debating whether I should reduce the tip thickness... I can always do that at the end without effecting tiller. I put it up on the tiller tree to have a look. Bending nicely, but not a bunch, but I safely pulled it to 45# (target weight), and it didn't fly apart. Phew. String alignment is bang on... no twist. Yah!

Offline PEARL DRUMS

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Re: Working on a static recurve
« Reply #19 on: February 07, 2014, 05:25:36 pm »
You will know if the tips needs reduction after the first full draw shot. It'll be smooth or chatter your teeth! Id guess you can take some depth off them.
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 PatM

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Re: Working on a static recurve
« Reply #20 on: February 07, 2014, 05:34:21 pm »
I just cut the V with a very fine toothed Japanese saw and then made the tapered point fine-tuned to fit. I did get a very nice fit but you can make a pretty sloppy joint and  use epoxy as a gap filler and hide  it under the backing and underlay.
 Shoot the bow for a while with the chunky tips and then reduce the width if it looks like the string is reliably hitting the groove.
 If you had run your backing strip right to the end you can really trap the tips to the back considerably and leave the belly side a hair wider.
 I would be most concerned that the tips could just split right off at mid curve myself.

Offline adb

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Re: Working on a static recurve
« Reply #21 on: February 07, 2014, 05:39:39 pm »
You will know if the tips needs reduction after the first full draw shot. It'll be smooth or chatter your teeth! Id guess you can take some depth off them.

Yah... that's what I was thinkin'. It'll be a fun game reducing tip mass and not weakening them. As it stands, I think these tips would probably loosen your fillings!

Offline adb

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Re: Working on a static recurve
« Reply #22 on: February 07, 2014, 05:46:09 pm »
I just cut the V with a very fine toothed Japanese saw and then made the tapered point fine-tuned to fit. I did get a very nice fit but you can make a pretty sloppy joint and  use epoxy as a gap filler and hide  it under the backing and underlay.
 Shoot the bow for a while with the chunky tips and then reduce the width if it looks like the string is reliably hitting the groove.
 If you had run your backing strip right to the end you can really trap the tips to the back considerably and leave the belly side a hair wider.
 I would be most concerned that the tips could just split right off at mid curve myself.

Thanks, Pat. I never thought of a fine toothed hand saw. I was using my bandsaw. It's nice and quick, plenty accurate, but the final cut was too rough for a good strong glue joint IMHO. I even tried using my miter saw. It made a smooth cut, but wasn't good enough at the point of the V. I also made the mistake of profiling the tip taper first, instead of the belly wood taper. I realise now, you have to cut the inside V of the splice on the belly wood first, and then fit and shape the outside tip splice to that. Live and learn.  ::)

Offline PatM

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Re: Working on a static recurve
« Reply #23 on: February 07, 2014, 05:47:53 pm »
 I don't know. I've made some pretty chunky Grumley style tips and I was pretty happy with the feel of the shot despite the added weight.
 Still, you can just keep filing and scraping on them until you lose your nerve and call it quits. The Grumley I made had chunky tips and I then reduced the sides to allow the loop to pass on either side and left a bridge/brush nock. Unfortunately never got to test the difference as the bow died in a 'floor tillering" accident.
 Here's a pic of the tip of the ill-fated bow on the left.

Offline adb

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Re: Working on a static recurve
« Reply #24 on: February 07, 2014, 05:49:35 pm »
Beautiful tips.

Offline Danzn Bar

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Re: Working on a static recurve
« Reply #25 on: February 07, 2014, 08:01:17 pm »
Wow adb that's looking nice, can wait to see that one bending. 
DBar
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Offline Cameroo

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Re: Working on a static recurve
« Reply #26 on: February 07, 2014, 08:02:39 pm »
I can't answer any questions, but that's looking pretty sweet Adam!

I was kinda thinking the same as Pat.  If they break, it will likely be along a growth ring around mid-curve (assuming I'm seeing the grain correctly).

Offline adb

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Re: Working on a static recurve
« Reply #27 on: February 07, 2014, 08:10:01 pm »
Thanks, Cam! How's that big elm warbow comin'?

Offline Cameroo

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Re: Working on a static recurve
« Reply #28 on: February 07, 2014, 08:15:57 pm »
Haven't touched it since heat treating/tip alignment last weekend.  Going to start at it again tomorrow.

Offline PatM

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Re: Working on a static recurve
« Reply #29 on: February 08, 2014, 02:21:46 pm »
Any updates?