Belly plugs

[Jim Davis]

There are cases where leaving a hole open would certainly bring failure. I made that rectangular plug before I finished tillering the bow. I think the limb would have broken before I got it tillered if I had not repaired the belly.

The thing is, wood is much stronger in tension than compression, so the belly needs to have no large voids or bad wood..

[ravenbeak]

Hey Ryan,

what I use and feel to be the best is powdered stone.  I get it from a wood turners supply in the usa.  I use mostly the green - malachite and the dark blue - lapis.   

Mixed with a bit of gel ca glue it works amazing and polishes up nice too.    Will fill right to the edges of the whole and very little voids.

I use it for my circular arrow pass on the longbows and also for filling knot holes from dead branches.

cheers,

Jamie

[penderbender]

Jamie you did some with copper filings that looked really nice.

[ravenbeak]

Hey you are correct.  Have we met?

I really like the copper dust as well.  It is a bit tricky to work with because it sets up so fast.

I have also used grey sand from the kids sand bow.  That worked great also.

I have never liked the look of sawdust and glue.

[wizardgoat]

Thanks Jamie. I knew you used stone for arrow passes, not for belly knots.
I'll have to check that out. I've seen Simon use aluminum I believe.
I'm not wild about the look of sawdust either, thanks for your input.

[Markus]

Pieces of sinew made into a ball saturated with hide glue and stuffed into the hole workes also.

[penderbender]

Ravenbeak no we have not met haha I emailed you about sinew a while ago. Look forward to attending one of your arrow courses. Cheers

[Dakota Kid]

Baking soda and ca glue is often used to repair missing sections of ivory bridges on string instruments. When it sets up it's as easily as hard as quartz. There's a chemical reaction that takes place, but I'm not sure of the details without looking it up. Next time you got your ca glue out mix it with a little baking soda and let it dry on your table. After it sets up test it's strength, I was surprised.

[mikekeswick]

Some interesting thoughts here. I've used powdered stones as well. Look at a traditional artists shop that sells pigments.

[Del the cat]

I've been re-reading Del's blog and way back he used a piece of limb as a plug so the end result looked like a knot. He only seemed to use it once and never mentioned it again. It sounded like a real slick idea.

Yeah, that was for decorative effect, the limb plug has pith in the centre which may create a weak point so I didn't do it again (it was also a lot of work)
Personally I don't like the idea of stone etc. I think the ideal plug should have the same properties as the material around it. I try to use an off cut from the same log, of saw dust/epoxy with the dust being from the same log.
I think the killer is where you have either buried knots which are invisible or small knots which go bigger and deeper than you realise giving effectively a cavity.
Del

[Eric Krewson]

I have done several of these half moon plugs, they work but don't last for the long haul, usually cracking in a year or so of shooting.