Primitive Archer
Main Discussion Area => Bows => Topic started by: blades7558 on August 24, 2011, 12:09:39 pm
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I plan on making a crossbow for my friend who was very impressed with my 45 lb version. I was wondering if beech would be a good wood for 80 lbs or so at 20 inches. The stave I have selected is about 48 inches long. It does have a wiley knot in the one limb but I plan on backing it maybe with sinew...
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Grind out a bow from an old leaf spring. Wood crossbow ballast can be disappointing.
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Beech has quite short fibers. I personally would go for a 'better' wood.
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I will eventually go to metal for the prod but I still like the idea of wood. I made one out of redoak and the cast was ok.. itwas 45 lbs. I don't have much better wood then that any suggestions?
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Could this be a language thing, over here in the UK beech is very brittle short fiber stuff (fagus sylvatica) but i hear over in the US beeck is what we call hornbeam which i hear is great bow wood.
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American Hornbeam is also called Blue Beech but it is not a true beech. Our beechs are very similar to the European variety.
I've never made a bow from beech. I have seen long bows made from beech but don't know how it would work as a short, high weight crossbow prod.
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American Hornbeam is quite different that Hop Hornbeam in strength Dwardo. I have a big American Beech in the back yard that is hard as a stinkin rock! I have no idea how strong in tension or compression it is however. I would think heat treated elm would be a great choice for this project. That stuff doesnt come apart at the seams if handled correctly.
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There is a fundamental problem with wooden crossbow prods, which is why they weren't in use much. To get a lot of poundage from a short draw and a short bow is difficult.
I think you need a good wood or build the prod with some deflex so that it doesn't get over strained just bracing the darned thing.
Alternatively something with maybe a Bamboo back (Maybe bamboo back, belly and core... with maybe some extra bamboo somewhere ::)).
To get a high draw weight and it looking 'right' I'd go nice and wide, rounded back, enough deflex to take it to almost brace and bit of reflex very near the tips.
This is something that's on my 'to do' list and that's how I plan to do it.
Remember to make the bow slightly curved so it's tips sit higher that the centre, to stop excess string pressure on the stock/track.
Let us know how you get on.
Del
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Thanks everyone for your input. Dell deflexing the prod is some thing I should have thought of on my red oak, it has a 2 inch set now and the cast is not as good as I had planned. Ithe beech im going to try and make the new prob from is 1.5 wide, I wish it was a little wider but maybe if I lower the weight expectancy to 60 lbs it will be more cooperative. I plan on making it like a mini D style bow so I can get as much out if the wood as possible. Wish me luck!