Thin bellied bow? Handles keep popping?I may have a solution.....

[mikaluger (Mick Kay)]

Hi guys,

Over Christmas I was a little miffed. My two best bows had major dramas develop. Within days of each other the handles on both bows popped off. This was rather disappointing as one was my favourite bow, being my osage flatbow and the other a sweet pacific yew bow I made for a friend of mine. Both were posted here last year. My bows no dot have fibre glass in them and are not the "layed up" type of bows. Some guys would call these type of bows "stick" bows.

Both these bows had a thing in common, they had thin belly's that extended thru the handle/riser area. Not ideal, I know, but that is how the material turned out and that was all I had to work with. Both these bows are real performers, but after about 800/1000 arrows, "POP". Back to square one.

I did a bit of research on the net, and looking at my bows that are still going strong I worked a couple of things out for myself. And after some frustrating weeks, I thought i would share my findings. I am only an amateur bowyer at best, and self taught, so feel free to add to, or correct my thoughts here at any time!!!!!!!

-If you can, use belly wood at least 20mm thick. Add layers on top this for your handle.
-start your fades well into the bellywood.
-keep your riser as stiff as you can, or "static" and tiller your limbs to suit this.

Nothing to hard here, most guys would know this already.

Ok, what if like me, you get some osage or yew or similar and after you have roughed out your timber, the belly wont be as thick as you would like?
Make your bow as usual. Then this is what I have done to stop, or at least try and curb this annoying problem.

-not not use a single piece of timber for your riser, use 3 or 4 thinner pieces and build up your riser. I believe this adds a little more "flex" in your riser.
-add another piece of backing on to the back of the bow, adjacent and the same length as your intended riser. This makes your riser area a little stiffer. It looks pretty cool too!
- make your fades a little longer. I am doing mine at 90 to 100mm now.
- The last thing I am now doing is "pinning" or "dowelling" my risers. After shaping the fades, drilling a 3mm hole, on the opposite angle to my riser, through the first or second layer of riser material and into the belly wood, inserting bamboo skewers and gluing these in with TB3. A little tricky, but guess what, it works. No ill affects so far. My theory here is that this will help stop the first layer of the riser lifting off the belly wood.

I have added a few photos.

This is something I thought I would share, as it has worked for me........so far!!!!! 
If anybody would like to add to this and or correct anything I have said.......... all the better I say!

mick.

[adb]

Some of your observations are correct. If your laminate bow is too thin thru the grip, and the bow bends thru the handle, any riser will simply pop off. I make my belly laminate thickness a minimum of 1/2", regardless of material. And yes, multiple layers are stronger if done correctly. Not because they flex a bit, because there are more glue lines. A well done glue line is stronger than the surrounding wood. If you don't want your bow to bend through the handle, make it that way. It's very difficult to add a riser to a bow that does.

Yes, taper your fades gradually and keep them smooth. They will be less likely to fail. However, I don't believe pinning your fades will do any good. Actually, I think it makes them weaker. They're like a spliced joint... it is plenty strong if done correctly, and is in fact weaker with pins.

You can add a material like leather to a bow's grip to build up the riser. Ask Cameroo... he had this challenge recently, and came through it with flying colors!

[vinemaplebows]

A power lam under the backing would be my cure.


vmb

[Easternarcher]

x2 on the power lam.
I've never had a handle pop off even with wood slats at less than 1/2 in. thickness when I use a powerlam.

[mikekeswick]

As said the pins actually weaken the joint a little.
Powerlams are the way to go. Try one and you'll be sold! Just make sure the edges are actually paperthin and the end of the taper isn't too steep or else you'll get shoddy gluelines.

[Onebowonder]

No master joiner am I, ...but I do not understand the physics of why these pins would weaken the joint in any appreciable way?  Can someone explain why it would be in fact weaker than the straight flat glue line?

OneBow