Author Topic: elb handle splice ratio  (Read 3909 times)

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Offline stuckinthemud

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elb handle splice ratio
« on: July 29, 2017, 09:18:27 am »
Quick question, I've cut v-splice to join two blackthorn billets at the handle. i've used a 4:1 ratio resulting in a 3" long splice. Is this ok? I'm making a 72" long ELB target weight is over 50#

Offline Del the cat

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Re: elb handle splice ratio
« Reply #1 on: July 29, 2017, 09:32:36 am »
I use a Z splice these days, I have done Vs and I have had one fail (managed to repair it ) I'd go as long as possible depending on how much stiff handle you are allowing.
One common mistake is to mark out a 4" splice but find that when the bow is narrowed to final width the splice has lost a lot of length.
Draw up the final width on the back of the billets and mark the splice to length on that and continue the lines out to full width. (Hope that makes sense)
Last one I did was a Z of about 3.75" length so that gives 11.25" of glue line
Judging by that I'd suggest going to 5" V or a Z.
Just checked my copy of "Billets to Bows" (a good read) he shows the 'Z' and 2 prong 'W' being 4" and the V being about half as long again)

One cast iron belt and braces trick which I used on a repair is a very shallow scoop off the back of the finished splice, overlapping the ends and a Yew sapwood patch over the splice and bulging slightly over the scoop (This makes a good looking slight swell at the grip).
I've used a similar trick when splicing Yew belly billets (for a crossbow prod) which will have a continuous backing, you can get away with a very short splice then
Del :BB
« Last Edit: July 29, 2017, 09:37:35 am by Del the cat »
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Offline stuckinthemud

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Re: elb handle splice ratio
« Reply #2 on: July 29, 2017, 09:52:55 am »
Hi Del, I've taken that section of the bow to final width (7/8)  to try to avoid that very situation, but, I'm not keen to use a z-splice as I'm hand-cutting (no band saw) . Guess I need to take this out to 6". Any thoughts on pegging the joint to give some mechanical advantage?

Offline Del the cat

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Re: elb handle splice ratio
« Reply #3 on: July 29, 2017, 11:10:18 am »
IMO pegging won't do much other than help hold it together whilst gluing.
The only thing I'd recommend for absolute certainty is the thin back overlay, it just gives a continuous layer to bridge the join.
Think about the strength of a butt joint compared to a butt joint with a plate lapped over the join.
It only has to be 1/8" thick to give a huge increase in glue area and provide wood in tension !
Del
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Offline stuckinthemud

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Re: elb handle splice ratio
« Reply #4 on: July 29, 2017, 12:50:59 pm »
I'll definitely add the patch, I have a small offcut that's perfect

Offline Del the cat

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Re: elb handle splice ratio
« Reply #5 on: July 29, 2017, 01:52:12 pm »
Out of interest what glue are you using?
Del
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Offline DC

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Re: elb handle splice ratio
« Reply #6 on: July 29, 2017, 02:02:23 pm »
The patch on the back also hides a less than perfect glue line. But you wouldn't have one of those ;D ;D ;D

Offline stuckinthemud

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Re: elb handle splice ratio
« Reply #7 on: July 29, 2017, 02:54:08 pm »
Nice of you to say that DC but my glue lines are slightly less than perfect, so I  was going with cascamite as the white finish of the resin looks ok on a white timber. 
« Last Edit: July 29, 2017, 02:58:31 pm by stuckinthemud »

Offline Del the cat

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Re: elb handle splice ratio
« Reply #8 on: July 29, 2017, 04:11:22 pm »
Nice of you to say that DC but my glue lines are slightly less than perfect, so I  was going with cascamite as the white finish of the resin looks ok on a white timber.
Yeah, Cascamite/Resinte/whatevertite works for me :)
Del
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mikekeswick

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Re: elb handle splice ratio
« Reply #9 on: July 30, 2017, 03:36:14 am »
You can mix it with some sawdust to improve gap filling.

Offline WillS

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Re: elb handle splice ratio
« Reply #10 on: July 30, 2017, 03:50:50 pm »
Make sure you boil both ends after cutting and fit them together while hot, then allow them to fully cool.  You can get away with the most disgusting hand-sawn splices that way ;)

I've done a couple by hand (don't have any power tools!) and they've been fine if I use the boiling method.

Limbit

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Re: elb handle splice ratio
« Reply #11 on: August 01, 2017, 12:59:43 am »
A lot of guys do the W splice for smaller splices since it has increased surface area. I just use a 4-5inch V splice on just about anything I splice. I wouldn't go shorter than 4 inches because (like other guys said) when you shape the handle you may reduce the splice a bit while narrowing. Like other people said, steam the splices for about twenty minutes and clap together for a few days to make a perfect splice. Also, look at it carefully after steaming and before clamping. You may have not cut it perfectly due to using a hand saw, and while it is hot, you can bend it straight and clamp it through the splice (assuming your wood is tough enough). Use a viscous glue and don't clamp it too tight while glueing or too much glue might shoot out of the gap creating a weak splice. Obviously, also wash the splice with alcohol or dish soap before gluing if using an oily wood. As long as you aren't making a crazy high poundage ELB, this splice works just fine. You can even use it in bendable handles. Plus, it is a whole lot easier to find usable wood!

Offline WillS

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Re: elb handle splice ratio
« Reply #12 on: August 01, 2017, 02:01:57 am »
You can actually do it on crazy high poundage bows!  I know it's been done on a 160lb bow which bends through the handle.  It was a 7" splice though...

mikekeswick

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Re: elb handle splice ratio
« Reply #13 on: August 01, 2017, 03:31:28 am »
I would warn against trying to 'degrease' oily woods as acetone,alcohol etc actually just draw more oilks to the surface. Most good moderns glues aren't affected by oil content in the wood.

Offline bradsmith2010

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Re: elb handle splice ratio
« Reply #14 on: August 03, 2017, 07:35:34 pm »
 (-P