Primitive Archer
Main Discussion Area => Bows => Topic started by: Tommy D on March 21, 2010, 03:30:19 pm
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I have been trying to make a bamboo backed bow for some time now. I live in EAST Africa and I have been struggling to get good wood for the limbs as most timber yards only stock a few species (certainly none of the well known West African Bow woods well documented in bow building circles).
So far I have made one successful bamboo backed bow using a yew left over from a self bow I built and I don t think that my tillering is too bad but so far all my other attempts have failed!
I have had 2 attempts with Eucalyptus chrysal; I have tried a local wood called African Camphor (Ocotea usambarensis) and it chrysalled as well.
The only other woods that are stocked are Cypress (which I am guessing wont be great), African Mahogany and one called Podocarpus spp. which I am told is distantly related to yew?
Does anyone know anything about these woods that I have mentioned and whether they might be suitable for bow building? Or have any other suggestions?
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Well... you are much like me, and live in a bow wood desert. Unfotunately, if I want to make bows, I have to import my wood.
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I used some american Cypress and its quite a bit like Eastern Red Cedar. It was from a board and backed with canvas. It was okay. If I were you I'd try the African Mahogany. I'd guess it would be a good as Cherry or maybe Ash. Pick a board that's heavy compared to the rest, and probably you'll need back it. Good Luck!
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Here in Japan I have used Podocarpus macrophylla with good results.
Not sure about physical properties of your species but it may be similar.....
The wood depends much where it grew, and growing conditions. We have poor soil here where it grows so its usually much denser than ones people grow in garden. Treat similar to juniper or low density yew.
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The Podocarpus I have is white wood but very knot free. I guess I will try this one if Far East Archer has had some luck with it. Did you have to back it and how did you use the grains. Do you think it is better in tension or compression?
Our mahogany has very course grains and is actually quite soft so I am not so sure about this one. Although I don't live in a bow wood desert most African bows are made from fairly narrow saplings of a few certain species that dont grow big enough to get lumber from.
I read somewhere that Eucalyptus tends to chrysal badly - have other people experienced this?
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Oh yeah we also have Juniperus procera - East African Pencil Cedar. It is beautiful wood but very brittle so I have been put off trying it. It will split if you tried to nail it. I dont know if this would work with a backing?
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Where in East Africa? I used to live near Nairobi Kenya :)
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Junipers will make a good bow. After looking at the data sheet, African pencil cedar (Juniperus procera) looks pretty good...so I would recommend that you experiment with the cedar. It's probably cheap as well.
If you can cut your own cedar, that would be the best choice. Cedar boards might work but you will probably need to back the bow with rawhide or sinew.
Here is a data sheet on Juniperous procera:
---http://www.fpl.fs.fed.us/documnts/TechSheets/Chudnoff/African/htmlDocs_africa/Juniperusprocera.html
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Born just outside of Nairobi but work in Tanzania now Jesse. Thanks for the info Jackcrafty. I will try the cedar.
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Jambo Tommy. Have you heard of an area called South B? That was my neighborhood.
Wish I could help with the wood but I dont have a clue what you have there :)
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You are lucky to have no knots!
Yes, it is a white color wood, sometimes its look peach color or have different color growth ring, but mostly whitish.
Well, I have try both. Unbacked bow work well if its clean back.
I have backed with bamboo no problem, so from my experience this wood is better in compression than tension, but it can be made unbacked.
You should test some scrap piece before make bow.
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Have you tried laminating any of the different woods you have together? Just a thought.
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What would the advantage of this be? What is the advantage of a tri-lam? I know to some this may sound like a silly question but fear that if I can't get it right with bamboo backing it would be even more work to do a tri-lam and break that one!
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Interesting that the Australian Pine post came up - I didnt realise it until it was mentioned but we have a lot of Casuarina on the East African coast and so I would like to hear more on the subject!
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I read somewhere that Eucalyptus tends to chrysal badly - have other people experienced this?
eucalyptus is not one tree but a category of trees that produce eucalyptus oil in the leaves. most 'Gum' trees here in oz are eucalypts. some of them are fast growing crap wood, some are slow growing excellent wood (for bows and other uses), further to this the conditions an individual tree grows in will have an impact on it's quality. a tree that has had good contions will not produce a quality wood like a tree that has had harder conditions.
we have a species here called spotted gum. if it grows on one side of the range (sea side) we don't use it, infact it's not even harvested. if it grows on the other side of the range it is harvested and used for all number of building uses and bows.
there is also a lot of african mahogany growing around me. it is apparently no good for bows. the small amounts i'bve used (not for bows or bow limbs) has been hard but brittle and snaps when you look at it.
if i was you i'd be looking for a slow growing tree in hard conditions. find a good branch or trunk for a stave, roughing it out to floor tillered. paint the back and ends to stop it cracking while it drys and chuck it in an air conditioned room for a month or until it stops looing weight and give that a go.
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Otis,
Thanks for your message. What species of gum make good bows - we have loads. They were originally planted by the settlers to drain swaps and provide fuel for the railways. Some common ones are Saligna and Blue Gums, but there are many species that have been introduced and I am sure I could find the good ones.
Do you ever use Australian Black wattle - that was introduced for tanins in the leather industry. Also Mimiosa trees from Australia.
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Tom,
black wattle is a commonly used name for a few different species of wattle (acacia) so it will depend but i know people have made some excellent bows from 'black wattle' (can't tell you which type). i have tried with the black wattle we have where i am and found it to be no good (split and cracked), but i hadn't seasoned it fully at the time and i know others have said the same thing with black wattle that isn't fully seasoned.
the good thing about many australian hardwoods is that the grain orientation is of little importance. infact it can often be used upside down or sideways. grain violations are not a concern, and it will handle a fair amount of grain runoff as long as the grain is running fairly well down the limb. but as i said in the last post the harder the conditions the tree grows in the better. draining swamps sounds like pretty ideal conditions for a lot of gum trees and so the wood may be to light and poor in quality. if you can find one on a rocky ridge or in poor conditions grab some.
grey ironbark is considered one of the best, but red ironbark is also good. http://www.hardwood.timber.net.au/species/ironbark_grey.htm
spotted gum is definitely one to try.
spotted gum http://www2.dpi.qld.gov.au/hardwoodsqld/10142.html
stringybark can work and i have used it before.
http://www.timber.net.au/?option=com_species&name=Yellow%20Stringybark&Itemid=472
cooktown ironwood is another i have used, although backing it is advised as i have found it very high in compression strength and can overpower itself. upto 1300kg per m3.
http://en.wikipedia.org/wiki/Erythrophleum_chlorostachys
jarrah also makes servicable bows.
http://en.wikipedia.org/wiki/Jarrah
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I would second the use of Ironbark and for aesthetic purposed would go for Red Ironbark even though it is not quite as strong as the Grey, however as both are stronger than most other woods it is not a problem. ;D
Have had mixed success with spotted gum and stringybark.
Craig.
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I have read that most Eucalyptus chrysalls easily - is this true - or very species specific? Has anyone made board bows out of it? Must it be backed? What diameter tree to you start with for a self bow? What is the best way to season it from scratch?
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I have read that most Eucalyptus chrysalls easily - is this true - or very species specific?
There are over 700 species of Eucalypt and yes some are brittle and will crystal readily. Otis has given you the name a number of trees that you can make good bows out of.
Has anyone made board bows out of it?
A number of the woods Otis mentioned are available in Australia as floor boards or decking boards and yes people have made plenty of board bows out of them.
Must it be backed?
Not necessarily, depends on the grain and annual ring orientation plus the weight of bow you are making. Same as any western/American tree.
What diameter tree to you start with for a self bow?
Its wood just like that in the West, so same rules apply, some have made bows out of 3inch saplings others from larger trees, it also depends on the type of bow you are after.
What is the best way to season it from scratch?
Split into staves, seal the ends leave the bark on or remove it and seal the back. some species check terribly no matter what you do.
Craig.
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I have read that most Eucalyptus chrysalls easily - is this true - or very species specific?
There are over 700 species of Eucalypt and yes some are brittle and will crystal readily. Otis has given you the name a number of trees that you can make good bows out of.
i have had stringybark chrysal. i doubt you could get ironwood to chrysal if you tried. its amazingly dense stuff. i don't think its fair to say eucalypts chrysal as a rule, however there are, as stated, 700 odd varieties, and some are pretty crap wood. the types i gave in the above post are a couple of woods more than worthy of a try.
What diameter tree to you start with for a self bow?
something 6"-12" round is a good start.
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Thanks for these replies. Going back to African Juniper - from these stats can anyone comment on whether it will work for bow wood? http://www.wood-database.com/lumber-identification/softwoods/african-juniper/
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i know nothing about it so i shouldn't say too much. but it does look to be very light at 500 odd kg per cubic meter.
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The stats on the African juniper look really good for a softwood. They are better than Eastern red cedar (US species), for example.