Types of wood

Hello,

While trying to learn about the different types of woods and how to use them, I came accross http://www.dummies.com/how-to/content/types-of-wood-for-woodworking.html .
I wanted to try to compile here (if that's ok with you) a list of types of woods with pros and cons and some tips to make it easier to choose for novice crossbow builders as myself.

PLEASE CORRECT ANY MISTAKES.

I'll try to compile it through research on the internet but any hands-on experience is welcome and edit it here.

Two basic types of woods:

Softwoods:




Hardwoods:


All of those can be natural or manufactured.

Whilst the manufactured woods are cheaper, I would recommend you stay away from those, especially plywood and chipboard.
If you really want to try using manufactured woods, the only one that I found any good was MDF/HDF.

Quite a task you've set yourself Arminius,as members here are from different countries and continents,pricing and availability will be a real headache.We have a couple of members from Africa on here,and some of the woods they mention I have'nt even heard of,let alone worked with,and I consider myself fairly knowledgeable about woods.Good luck with your project tho', you've taken on 
one hell of a challenge.
                               Hermit.

Did not actually think of that. Thanks, hope I'll make it.

I do really not like being the killjoy, but Arminius, do you consider it being a good idea starting an advising thread obviously without having any experience in woodworking/selection?

Why not just ask for some advice (after clearing some local things as mentioned above) and the answer of wood selection is relatively easy, then gain experience/develop knowledge, and eventually write a guide???

Personally I doubt that this question wasn´t answered in either the community or wiki a couple of times before.


The point of pricing:
Forget about the idea of building a proper crossbow without spending money.
Good wood is expensive and is going to be in the future.



Wood itself:
usually the harder the better,
the longer and compact (more late wood, little spring wood) the grain the better,
look for good grain cut, laminating can diminish grain cut weakness,
the stronger the bow the better the wood should be (reinforcements)


for example top choice: walnut / maple / ash / elderberry ...
medium choice: cherry, peer, plum, oak ...
normal choice: beech, birch...

(considering that you are probably not building a crossbow with several hundrets of pounds each of above selection will do the job when in right dimensions)


poor choice: everything that is lightweight or has little(no) grain structure (this includes mdf and hdf that are in my experience even worse to work with than plywood)



This selection can be continued almost open end, local availability dictates a lot.


But you have considered the point crossbows are prohibited in certain states around the world?

Rizzar

As you have noticed, I just wrote on what I have actual experience, mostly manufactured woods (sadly).


I had a look at the Wiki (http://crossbow.wikia.com/wiki/Wood_as_bow_material) but unfortunately, the links do (http://paleoplanet69529.yuku.com/topic/6213) not work anymore. That's why I started this thread to share what I learn as I go and help other people looking for the same thing.

What you just wrote is a big help!

In my experience, plywood splintered a lot easier than MDF which held up fine. In similar thicknesses it seemed also to hold much better. But I might just have been lucky.

Don't list prices, they vary too much from region to region and date to date.  Don't use "manufactured woods"  like MDF/HDF -- they have a tendency to dissolve or come apart under shock stress. 

Having been trained as a forester, and being a crossbow builder myself there are two bits of advice I would offer. 

First -- Always use the Latin name of the wood you're talking about, along with it's common name.  Common names vary from place to place; nearly every country and state has a wood called "ironwood" but the actual species varies around the globe, for example.

Second -- Do not use woods which are too soft, no matter how cheap or pretty they are, except for decorative inlays and such.  There is a universally accepted scale of wood hardness called the Janka scale, which is discussed here:

http://en.wikipedia.org/wiki/Janka_hardness_test 

as well as many other places on the internet.

The scale runs from 22 (five times softer than balsa!) to over 5000 (an Australian wood harder than Lignum vitae)

As a builder I would suggest that you NOT choose a wood which scores less than Janka 700, and preferably not less than 900.  This eliminates virtually all species of pine and fir -- those used commonly for building  houses and such.

I know this thread is over a year old but I wanted to revive it simply to add an excellent reference link for wood workers and for bowyers
http://www.wood-database.com/

Most of my experience is building stick bows and I find the wood database very useful. It has an extensive list of wood species listed by common and scientific names (important for comparisons) and lists the wood species average material properties in both metric and imperial. A few notes on evaluating material properties. They cannot be used in isolation, they are always relevant in relation to each other.

For example when evaluating bow woods for prods/limbs something with very high Modulus rupture (MOR) but high elastic modulus (MOE) will be tensile strong but break instead of bending. It could be described as brittle. Lower the the elastic modulus and you have a strong wood that will bend well before breaking. However if its compression strength is very weak in relation to its MOR then this same wood will tend to take set as its belly gets damaged from the excess bending. I find the actual numbers tend to be less important than their relation to each other. My method for using this site is to generate ratios for material properties and then compare them to established bow woods to get an idea of how well I should expect an unknown wood will perform. I will divide the MOR by the MOE (I know that I am flipping units when doing this, but it works). Then I will divide the MOR by the Crushing strength and get an idea of how compression strong the wood will likely be in relation to its tensile strength. You will find the best established bow woods tend to have high ratios in both these categories where as most other woods involve compromises in one way or another. None of this is scientific but it is a good ballpark starting point when looking through the stacks at a lumber store or evaluating a tree. Of course there is a lot of variation in an individual piece of wood. Tighter/wider growth rings, wood grain patterns, presence of knots, heartwood sapwood ratios, poor wood drying technique will all throw these figures for a loop when it comes to actually constructing a bow. Even the best bow wood can be made into marginal bows (or simply fire wood) when handled poorly, just as marginal wood can excel when designed and handled properly.

As for building stocks/tillers, I do not have much experience building crossbow stocks.
But I have built a 12gauge shotgun stock from Black Cherry and it has held up admirably to the abuses of shooting buckshot. I would not hesitate to use almost any hardwood from a fruit or nut tree as well as more common woods like sugar maple or oak. I bet any of these wood would work well, feel free to correct me if I am wrong.