First Bow Spotted Gum

Message

chodoboy · #1 Post by **chodoboy** » Fri Jul 31, 2009 1:51 pm

I just finished my first longbow the other day it was all going great looked like the limbs seemed to be drawing evenly although i was worried about one limb that had an imperfection in the timber. Just tried to string it to test it with some arrows when SNAP the limb i was worried about broke.

The question i want to ask is about the staff. Is it important to get a proper bow staff cause due to availability in my area I used a 36x36 finished section of spotted gum?

looseplucker · #2 Post by **looseplucker** » Fri Jul 31, 2009 1:56 pm

Hello

sorry to hear it went bang on you - perhaps if you post some piccies and also tell us the dimensions of the limbs? - where did it snap? What did the imperfection look like?

Spotted gum is pretty reliable and you can normally get a serviceable bow from a floorboard with the right grain. I've had one SG board bow develop cracks running off the side but have wrapped in silk and epoxy.

chodoboy · #3 Post by **chodoboy** » Fri Jul 31, 2009 2:34 pm

the bow was 1940 long in the center 35 wide x 32 deep, it tapered out to 18mm wide at the tips and was 13mm deep along most of the arms the wood had a resin like section in it like it had been damaged while growing it looked like dried sap. I will try upload a pic but i don't have one of the finished product just one near the end. I'm going to start another one and hopefully it wont have the same outcome. It snapped near the center of the lower limb.

looseplucker · #4 Post by **looseplucker** » Fri Jul 31, 2009 3:04 pm

Probably a place to start is to look at the dimensions - this is assuming a standard flatbow - not a pyramid or anything.

For a bow 68" nock to nock try the following dimensions:

Handle area - about 1" wide and about the depth you already have it. The handle is ideally about 4" long. Best to mark out 2" either side of true centre.

Then from where the handle ends have about 2.5" for it to widen out to the widest point which should be around 2" or 50mm

Keep the width of 50mm going until the midlimb - this will be about 14" or 360mm from the flares

The thickness of the bow at the flares, assuming a correct fade out will be about 13-15mm - and you should have a continuous taper to the tips - with that being about 9mm.

These measurements are a guide only - but I've made a couple of board bows based on these which shoot ok.

You could also consider getting some bamboo flooring - vertical - and playing around with that - bit more forgiving - Kimall has posted a good thread on this called Newbie Bow Makers.

Good luck

otis.drum · #5 Post by **otis.drum** » Fri Jul 31, 2009 9:48 pm

i'm with looseplucker. you need to change your dimensions. your tips look way too big in both width and thickness.

give it another go. good luck.

Glenn · #6 Post by **Glenn** » Sat Aug 01, 2009 7:31 am

chodoboy at 18mm wide and 13mm deep your tips are far too stiff and you can see it in the photos, they would have been placing your mid limbs under a lot of extra pressure even for a bow of that length. Have a go at Loosepluckers dimensions they are a lot more reasonable. Next time when you tiller your bow make the limbs bend all the way from the handle fadeouts to the tips but make sure the limbs bend gradually less as they near the tips, you will have much better results and outcome...Glenn...

ichiban · #7 Post by **ichiban** » Sun Aug 02, 2009 4:43 pm

dont worry, its an experiance esspecialy spotted gum, every1 raves about how good it is but in my oppinion it will make a bow but not a highly stressed one. last week i made a spotted gum self bow 68" long, drawing 30@28" all was well and good but when i went for the final inch of draw BANG the whole limb snaped right through (and hit me....) so i think spotty is ok but i would be more inclined to use ash honestly as this isnt the first time a spotty gum bow has blown up on me.

looseplucker · #8 Post by **looseplucker** » Mon Aug 03, 2009 9:32 am

And even with the right dimensions they can still go - that happened with some bamboo on the weekend

Glenn · #9 Post by **Glenn** » Mon Aug 03, 2009 10:04 am

Any bow made of any timber can break, even overbuilt low poundge bows can, and do break. Tiller and limb design are very important to the longevity of a selfbow...Glenn...

ichiban · #10 Post by **ichiban** » Mon Aug 03, 2009 1:02 pm

to right glenn.... maby this belongs in the wood v glass section hehe.
there is a good deal of skill involved in reading the wood grain, as long as its PERFECTLY stright you have good odds but the smallest wiggle could be the end of the bow sadly...so i went out and bought some hickory

Ozbow

First Bow Spotted Gum

First Bow Spotted Gum

Re: First Bow Spotted Gum

Re: First Bow Spotted Gum

Re: First Bow Spotted Gum

Re: First Bow Spotted Gum

Re: First Bow Spotted Gum

Re: First Bow Spotted Gum

Re: First Bow Spotted Gum

Re: First Bow Spotted Gum

Re: First Bow Spotted Gum