dimensions for a bow

[outbackarcher]

i got a new spotted gum stave a while ago and roughed it out and it seemed extraordinarly stiff so i removed wood, exercised limbs, not enough wood off , remove some more wood still way stiff, back to the vice repeat steps over and over and over again............

bow still a little bit stiff but has gained a lot of set and i now realise that spotted gum is well very stiff!!!!!!

so i am looking for new dimensions for a new stave and wondering if any of you talented, wise, resourcefull people who have had success in making spotted gum bows have any preconcived dimensions.

P.S desired bow weight 25-30@25" (yes im slightly short and weak) (dont blame me blame genetics)

lewis

[Mike-dy]

If you haven't read them yet get the Traditional Bowyers Bibles (all four of them) They'll give you plenty to think about, Length, mass , SG, MC, width etc all play a part in how the bow will perform.
I need to go back and read again, I would recommend these books to anyone considering building a self bow, or even a laminated bow.
Cheers,
Mike

[Glenn]

Lewis, one of the best books to buy to get starded on is "The Bent Stick" by Paul Comstock, it's nicely written and very simple. It gives you a nice layout for a flatbow that suits many Australian timbers...Glenn...

[Mike-dy]

I'd agree with Glenn on this too, Paul is also one of the authors in the Bowyers Bibles.
Mike

[GrahameA]

Morning Lewis

so i am looking for new dimensions for a new stave and wondering if any of you talented, wise, resourcefull people who have had success in making spotted gum bows have any preconcived dimensions.

P.S desired bow weight 25-30@25" (yes im slightly short and weak) (dont blame me blame genetics)

lewis

If I was looking at build a bow around that weight and from spotted gum I would probably build it from a floorboard. And it would probably have a profile of a D-Bow, i.e. an "English" Longbow. As long as you do not shoot ultralight arrows from it it will be fine. May not be the greatest bow of all time but you can make it in a couple of hours and it will not break the bank. The hardest thing will be digging through the timber at your local supplier. Look real careful for a piece with good grain. If you do not know what to look for in grain then start reading all the postings on this site concerning selfbows.

My general approach to making said bow is that being a little long, may slow it down but it will be harder to break.

Back to the bow. The depth of the bow is already determined by the thickness of the board. It would be a full compass bow - that it is will bend through the handle. Do not taper the back of the bow. Length - around six foot to 6 and a half foot if you have a longish draw. "As big as the archer plus a bit."

So some rough measurements. Mark out a handle area - say 3" either side of centre - that will be one inch wide. From there taper it down to three-quarters of an inch wide and three-quarters of an inch deep at the nocks and round the belly to a "D" - or something, maybe a flattish "D" and take the sharp edge off the back. Try it on on the tiller. That may be a little heavy and if so take a bit more off - increase the taper - but do it gently.

Caveat - I rarely build bows because I am not good at it but at least they are some starting dimensions.

[outbackarcher]

thank you all for the help, ive heard of the traditional bowyers bibles before but not 'the bent stick' by paul comstock sounds like a nice book to get.

grahameA

i already have 3 staves 19mmT 35mmw and 6ft long. its got okay grain maybe 1-2 run off per limb but it is a little wavy. your dimensions sound like they would make a nice little bow.

ill try to get my hands on these books that have been suggested.
does any one know where to get 'the bent stick' by paul comstock ?

lewis

[Len]

outbackarcher, read what Grahame said and read it again as its great advice for a beginner. If your board is 19mm in the centre then your tips will probably want to be about 10mm thick at tips and maybe 14mm wide. This is bigger than I would make the tips but is safer/easier for a beginner to start off with wider tips and learn how to get them slimmer with time. Good luck with it and stick at it.

[outbackarcher]

thanks lenn sounds like good dimensions. ill go draw them up right now. maybe even start roughin it out

lewis

[jape]

I can't find it in Aus but horsefeathersranch (the primitive archer guys) have it if you want to get it from USA http://www.horsefeathersranch.com/cgi-b ... add=action
and it is cheaper than 3Rivers so should alleviate the shipping costs a bit.

[kimall]

I would use a bamboo floor board for a first self bow at that lower poundage.In fact when you are coming to Toowoomba next mate let me know and I will give you one to have a go with.
Cheers KIM

[outbackarcher]

jape
thanks for the link mate i checked it out gonnas see if i can get dad to pay for it. well ill pay for he can pay postage.

kimall
dunno when im going to toowoomba but often go every weekend but this weekend dad and i are goin to tin can bay for the weekend. its a model helicopter and plane thing. thats my dads hobby these days.

[outbackarcher]

ok fellas just checked the thickness of the tips of the bow and they came out 7-8 mm thick 15 wide an bow is at least pulling 50 pounds .

i have no idea why it is so stiff. does any oneknow why my spotted gum is just really really stiff?

thank you, lewis

[pdccr]

No idea, i thought spotted gum was just naturally stiff...

[outbackarcher]

it is naturally stiff but the dimensions ive been given are saying it should be 30# not how heavy it is now. im not saying theyer demensions are wrong, but every peice of wood different.
this spotted gum i have must be stiff compared to other spotted gum.

lewis

[pdccr]

Oh in that case i guess your right, you must just have a stiff stave. Have you backed it yet?

[outbackarcher]

yep one layer of silk and pva glue.

lewis

[pdccr]

Ok i dont know, im sort of new to bow building so i'd ask a pro

[GrahameA]

Hood Morning Lewis

it is naturally stiff but the dimensions ive been given are saying it should be 30# not how heavy it is now. im not saying theyer demensions are wrong, but every peice of wood different.
this spotted gum i have must be stiff compared to other spotted gum.

lewis

Wekk Done.

So the bow is overweight. Not an issue. Sink the Bow.

Very carefully

Thin down the bow. Sand/scrape a little off the belly of the bow and the weight will drop. So just sand/scrape until you get it to the weight you want. Remember to keep an eye on the tiller and a little bit at a time.

[outbackarcher]

ok, ok my skills at the keyboard arent that good and my spacebar is stuffed, pratically have to punch it to space, so after ive done my home work, its off to the shed!

thank you, lewis