Author Topic: A better glue up method  (Read 2931 times)

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Offline fiddler49

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A better glue up method
« on: July 16, 2013, 02:44:40 am »
I have been using C clamps and spring clamps but I had some problems with the glue lines and backings sliding sideways as the pressure is added so I tried wrapping with a  cord. The cord is much easier and quicker to apply plus the backing edges self align. Another cool thing is you can put a fresh glued and wrapped limb between chairs
and push in the middle of limb to induce reflex. The reflex stays without adding weight. Plus it's easier to clean off excess glue along edges to check glue lines. Here's some pics
of a tri lam take down, purple heart belly, hickory core, ash back using tight bond 3. With induced reflex added to limbs. The limbs are 2 7/16" wide x 30 1/2" long x 3/8" thick.
The bow has 3 inches of total reflex as measured from the back to a stretched string between the nocks. 69" ntn, 65 lbs at 31" cheers fiddler49

Offline fiddler49

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Re: A better glue up method
« Reply #1 on: July 16, 2013, 02:50:25 am »
Here's a few more pics of tri lam Alaska style take down. cheers fiddler49

Offline Carson (CMB)

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Re: A better glue up method
« Reply #2 on: July 16, 2013, 03:36:38 am »
I havent much experience with glue-ups...burned my ash backed ERC glue-up.  But I personally like the idea of this method because I haven't invested in a bunch of clamps yet. 

I recall seeing some photos on here where wood shims were tapped in under the cord to increase "clamp" pressure after wrapping with cord.
"The bow is the old first lyre,
the mono chord, the initial rune of fine art
The humanities grew out from archery as a flower from a seed
No sooner did the soft, sweet note of the bow-string charm the ear of genius than music was born, and from music came poetry and painting and..." Maurice Thompso

mikekeswick

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Re: A better glue up method
« Reply #3 on: July 16, 2013, 04:34:43 am »
The wedges method was used by the Japanese primarily. It is very effective.
Fiddler - why don't you use innertubes? A trip to the local bike shop will probably see you leave with a box full for free! Plus you will get flawless gluelines if you prepared the lams well.
To stop the lams sliding sideways first wrap with packing tape every 6 inches or so before clamping. The lams can't move then.

Offline bubby

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Re: A better glue up method
« Reply #4 on: July 16, 2013, 03:34:37 pm »
The wedges method was used by the Japanese primarily. It is very effective.
Fiddler - why don't you use innertubes? A trip to the local bike shop will probably see you leave with a box full for free! Plus you will get flawless gluelines if you prepared the lams well.
To stop the lams sliding sideways first wrap with packing tape every 6 inches or so before clamping. The lams can't move then.

that's what I do, I had to promise the shop owner that I was gonna "recycle" them
failure is an option, everyone fails, it's how you handle it that matters.
The few the proud the 27🏹

Offline Easternarcher

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Re: A better glue up method
« Reply #5 on: July 16, 2013, 10:22:31 pm »
I second the inner tubes idea..
Also, I use shrink-wrap to hold everything together and control glue squeeszeout til I get the tubes on.
You can get the wrap at the dollar store in 4 inch widths on a spindle.

Offline fiddler49

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Re: A better glue up method
« Reply #6 on: July 16, 2013, 11:59:36 pm »
I have read about the inner tube method but never have seen it done. Maybe one of you lads could show how you use them with some pics. The problem with the C clamps is having enough of them. If I put the C clamps down the middle of the backing and lams, the edges of the backing curls up leaving a gap even with the spring clamps along the edges. I had to grind off the ash backing in that first pic and do it over with the cord. The cord I used is  cheap poly stuff that stretches slightly. Nylon mason line or kite string would also work. The thin cord lets you wipe away the excess glue and check the glue lines. Plus it dries faster and like I mentioned, you can easily put reflex into a limb just by bending it. No wedges needed. This is my fastest shooting take down so far.
cheers fiddler49

Offline JW_Halverson

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Re: A better glue up method
« Reply #7 on: July 17, 2013, 12:03:34 am »
The wedges method was used by the Japanese primarily. It is very effective.
Fiddler - why don't you use innertubes? A trip to the local bike shop will probably see you leave with a box full for free! Plus you will get flawless gluelines if you prepared the lams well.
To stop the lams sliding sideways first wrap with packing tape every 6 inches or so before clamping. The lams can't move then.

that's what I do, I had to promise the shop owner that I was gonna "recycle" them

HEY! Watch it bub!  Go "pedal" your puns somewhere else, this is my corner!

Love the innertube clamping system.  Had great luck with it.  Just be careful that you use even tension on the tubing and that you don't do too many wraps in one spot because you can cause excessive squeezeout. 
Guns have triggers. Bicycles have wheels. Trees and bows have wooden limbs.

mikekeswick

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Re: A better glue up method
« Reply #8 on: July 17, 2013, 04:09:44 am »
Fiddler - if you have to use clamps again anytime then use pressure plates to spread the load of the clamp. Cut squares of wood a little wider than the limb to be glued and about an inch thick. They can all be stuck to a piece of carpet /materail for ase of handling.

Offline Easternarcher

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Re: A better glue up method
« Reply #9 on: July 17, 2013, 09:23:08 am »
Fiddler, imagine wrapping an elastic around your finger...quite a bit of pressure right? but it is evenly distributed around your finger also.
I use bike inner tubes that simply have the valve cut out. I don't split the tubes lengthwise...these things last a good long while too.

I used to use two shorter ones and reverse the wrap in the other direction to help minimize twist, but not now.
I start at one end and wrap the tube over itself once to hold it and then stretch the thing quite tight before wrapping it around one full turn, stretch and repeat til you get to the other end. I just hold the tag end at the limb tip and use the shrinkwrap to wrap around it to hold it from unravelling. this works great IMO.

I must say I get great glue lines...Sometimes even surprise myself ;)
You can induce any deflex-reflex you want after that either on a form or strtegically places c or bar clamps along the limb...it only takes a couple and maybe one in the middle to hold it.

There's my method.

Offline bubby

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Re: A better glue up method
« Reply #10 on: July 17, 2013, 07:35:49 pm »
I defer to your mastery of the pun JW,didn't mean to step on your toes but it's hard not stepping on those big ol' clown shoes >:D
failure is an option, everyone fails, it's how you handle it that matters.
The few the proud the 27🏹

Offline lesken2011

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Re: A better glue up method
« Reply #11 on: July 17, 2013, 07:50:29 pm »
Hey, Fiddler. I learned how by following ADB's holmgard bow build along.  Here is the link.
http://www.primitivearcher.com/smf/index.php?topic=5129.0.
For by grace you have been saved through faith, and that not of yourselves; it is the gift of God, not of works, lest anyone should boast.

Ephesians 2:8-9

Kenny from Mississippi, USA

Offline adb

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Re: A better glue up method
« Reply #12 on: July 17, 2013, 09:44:58 pm »
I still do it the same way, but I leave a bit more space between the wraps now. Clamps are a total waste of money.