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Discussion Starter · #1 ·
I had to try it. Tested the forks out by lifting a 5 gallon bucket full of sand. Over 50 lbs. I could barely grip it but no pproblem. 20200508_161643.jpg 20200508_161717.jpg

There us 2.25 square inches of surface area in the joint. The glue is rated at 3500 psi. Half the area is shear and half tension.
 

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Glue, when applied correctly, is actually stronger than the wood. Guess what the strongest wood glue is?

In this case, the glue joint might not be the strongest, because of the end grain in the plywood involved.

-TL

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Well your the judge here and its your face thats behind those forks. I would def wear safety glasses. If you predrilled a small hole and then put a screw or two into the 2 that might be a good idea., and be safer. You could put a plug over the screw head if it bothered you. Or put a tight fitting pin in it.

Its a good bond and it shows you did well being able to pick up that much weight with it, but over time the wood will shrink and expand, the sling shot is going to be knocked around and the continual pressure from the bands , all these things will weaken the joint over time.

I do like the finish and the simplicity of your design. keep making them, and never settle for common (N.S.F.C)
 

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Titebond is polyvinyl-acetate glue. Fine woodworking magazine did their own test a few years back. They found it was the strongest glue for wood, even stronger than epoxy, easily stronger than the wood.

The strongest glue bond is along the grains. However wherever end grain is involved, the bond is much weaker. Plywood has a lot of desirable characteristics. But the presence of end grains in all edges is a fly in the ointment.

OP has a nice frame. I probably would include some sort of joineries to supplement the glue joint.

-TL

PS The frame seems to be for left-handed shooter. The handle is in front of the fork. The force is therefore trying to pull the glue joint apart. Putting the handle behind the fork is probably a better construction.
 

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Titebond woodglue
Ahhh ok, I thought you may have been using something different. I would recommend putting some dowels in soaked with titebond 2. To insure that everything will hold while putting a lot of stress on your forks from the rubber. That is my only concern the dowels will give you added insurance. Just my thoughts is all...

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Mojave Mo
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Titebond eh? Any relation to James? Sorry, long day. Nifty frame. Unlike a steak, a slingshot overdone is better than underdone. I haven't experienced a catastrophic failure at the sling range, just not gonna let it happen.

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Some of those old hide glues were used in woodworking. If I remember correctly you had to heat it up.
Yes, that is the best that they had. Used it for hundreds of years. You can get it to soften up by applying heat also. Some people who make musical instruments still use it. But the new stuff is just plain better in every case.
 

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Some of those old hide glues were used in woodworking. If I remember correctly you had to heat it up.
Yes, that is the best that they had. Used it for hundreds of years. You can get it to soften up by applying heat also. Some people who make musical instruments still use it. But the new stuff is just plain better in every case.
Modern flies are amazing. But I still use hide glue for some jobs where strength is not the biggest concern . But that being said, slingshot probably aren't one of those things.
 

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Discussion Starter · #17 ·
For some reason I was thinking about or dreaming of a dowel plate tool before I ever posted this sling. A dowel right through the center would do the trick. There are some nice videos posted on how to make one f r om some guy in AAustralia.Now I have some 3/16 or 1/4 inch angle iron around here somewhere.
 

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Dowels are so cheap and easy to buy though... of course a dowel plate tool would be fun to have.... something satisfying about driving wood through one!
 

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Ive even used colored pencils as dowels. You get a little ring of color and a colored dot in the middle. I still use glue on them no matter how tight the fit.
 
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