Toughest bow wood...

[Canadabowyer]

Originally posted by gobblegrunter:

 Infact, it seems as though, all woods are on level playing fields when it comes to laminated bows...do I have that correct?

Yes and of course no.As an example, if you build a glass laminated bow with all red elm limbs(light weight wood) and an identical glass laminated bow with all osage limbs( a heavier wood) the preformance( speed) will be very close with the red elm maybe just a few fps faster. But the bow will have a very different feel at the shot, with the osage bow having more recoil or hand shock. In a well designed bow the difference is slight and personally if I liked how a certain wood looked I wouldn't let the slight difference stop me from using a certain wood. Also If you use a very heavy wood for the riser and very light wood for the limbs you will get a very well behaved bow and if you were to use a very light wood for the riser and heavy wood for the limbs it wouldn't be as nice a bow to shoot. These are general rules and there are always individual bows that are the exception.  Bob

[Lee Robinson .]

Osage is indeed tough, but given the knots I don't know if I would rank it above Purple Heart or Bubinga in terms of riser strength...and IMO all of the above are too heavy to make ideal limb cores.

I would say bubinga is my favorite riser wood, and I would say one of the very best. There are many other excellent riser woods of course, such as purple heart, cocobollo, wenge, maple, and others, but I think bubinga has these all beat with purple heart coming in just as nice performance wise and durability wise, although not as nice looking. For limbs I like edge grain red elm and/or edge grain maple the best. Bamboo is also nice as a limb core, but I don't think it is as strong as the elm or maple. For a laminated bow though, all of these are fine.

Additionally, I know it has been said many times that the limb core doesn't matter much in a laminated bow, and that may be true to SOME degree in a bow that doesn't have much limb core, like a recurve...but for a bow with 0.250" total depth back to belly or more, I just can NOT accept such reasoning...and here is why. Say you have a bow with a 0.250" total thickness back to belly and with 0.086" of glass (2 x 0.043"), that would leave 0.164" of wood core...which is about 1/6." Some bows, such as a 66" length longbow may have a total depth from back to belly of 0.350"...and with 0.100" of glass that would leave 1/4" (0.250") of wood core. Get a raw lamination that is 1/6" to 1/4" thick (not in a bow) and that is 20" length lamination (about the length of the limbs in many bows) and bend it...and you can feel its resistence. Sure, in a laminated bow the glass does most of the work...but if one looks at this raw lamination and how it bends one will see variation in how it flexes based upon its grain and content (knots and such). This is why I like edge grain red elm, edge grain maple, or bamboo...as all are very consistent from one end of a lamination to the other end of the lamination...and bend more evenly than say something like bocote with its knots and variation that is seen in flat grain. Sure, the glass will hide such variation to a large degree, but I can't get past knowing the variation in the core is there with some limb woods, and that bothers me even if it is slight. A very knowledgeable bowyers once told me it doesn't matter what a limb's core is made of, and while I don't want to disagree with him, I would say "physics is physics" and if the core has variation I believe that variation remains even if minimized by the glass.

Now, that said, I have made up a bow with bocote in it, but I will only use very thin (0.025" - 0.030") veniers when I use something like that in a limb...allowing me to leave the majority of the core for a more consistent wood.

[wollelybugger]

Bamboo and Ipe make a nice bow. Osage gets my vote for a self bow.

[Rob DiStefano]

everyone has their faves and yet most any typical bow wood genus will work just fine for limbs and riser.  mine are ...

limbs - all bamboo or cane (not 'actionboo') cores and veneers
riser - any hardwood that looks purty

the *real* durability is in the finish, and fullerplast or any of the two part finishes will be stronger than the wood itself.

[Tajue17]

Yew is hard to beat and I have a few but YEW is very soft and softer than pine plus if it where a Yew selfbow you don't want to take it out in temps less than 20 degree's..

toughest and best woods are OSAGE all day long,, its fast, its tough and its reliable.  there are osage selfbows that have cracks, knot holes and dings all over them that are 30+ years old and still shooting great,,,, if it was 1 wood it would be Osage without a doubt.

everythign has a bad side and the only thing I can think of with osage is its heavy and the selfbows can have bit of handshock,, modern fiberglassed design would never see this.

[leftyfred]

Obviously the glass takes all the punishment in the limbs, so durability is a non-issue for the limb wood choices.  I have seen punky spalted maple hold together for years and years under glass with a good core and a good glue job.  For riser woods, my opinion is that Honduras Rosewood is the hardest, most durable wood available.  I base this opinion on how Honduras effects tooling.  Some may know my gig, however, I use all the woods spoken of and more.  LF

[Deerhntr]

Flat grained Red Elm for a core wood.

[Covey]

Originally posted by DesertDude:
I have always found laminated maple (action/diamond wood) very strong......

I agree, hard to beat! Maybe not as purdy as the exotics, but tough! Jason

[JamesV]

Mike,

I agree with you that wood choice isn't that important in a glass bow. I have built glass bows with many different wood cores and don't see much difference in performance from the same design. I have a nice straight grain piece of pine for my next victim.

James...............

[Huntschool]

I was told by a very, very good bowyer, that if we could find a way to trap just air between the glass lams on the limbs we would have the same performance as any wood...  Can you say carbon foam....  Life expectancy might come into play here.

[gobblegrunter]

This thread has become a full-out, college-caliber course! Thanks everyone!

Another question (probably a really stupid one)...when we talk about limb veneers, do most bowyers put clear glass over top of them (example: bocote veneers with clear glass), or is the glass only put overtop of the limb cores (i.e. clear, black, brown glass, etc.) themselves?

I guess the reason I ask is because I wonder...are you better off ordering a bow with black glass over the limbs rather than fancy wood veneers as far as toughness, durability, and longevity is concerned?

[gobblegrunter]

Originally posted by gobblegrunter:

Another question (probably a really stupid one)...when we talk about limb veneers, do most bowyers put clear glass over top of them (example: bocote veneers with clear glass), or is the glass only put overtop of the limb cores (i.e. clear, black, brown glass, etc.) themselves?

I guess the reason I ask is because I wonder...are you better off ordering a bow with black glass over the limbs rather than fancy wood veneers as far as toughness, durability, and longevity is concerned?

ttt, hopin for help with this other stupid question  :D  ...

[Lee Robinson .]

S-glass (ULZ) is superior to e-glass (ULS). Stats are available here...   http://www.gordoncomposites.com/products.htm  Unfortunately, S-glass isn't available in a good clear form. The natural that is available in s-glass is rather cloudy, so I use S-glass when I use black and e-glass when I use clear. Both are excellent, but s-glass does have a slight edge.

Carbon foam core certainly is already proven in performance, but it is also showing some concerns in terms of durability.

Also, when it comes to wood cores and durability, I would NOT confuse hardness with durability. Toughness = durability, but there are many hard woods that are dense as well...but more prone to crack due to their stiffness. Ebony is one such example. Yes, it is used often and used successfully, but it isn't near as durable as many other woods.

Also, I have shot some bows with osage in them that are certainly tough, but due to the limb mass it isn't my preference for a limb wood as I can feel more shock from it in some bow designs than other wood choices.

Again, these are just my opinions based upon my experiences.

[gobblegrunter]

Originally posted by Protege Longbows:
S-glass (ULZ) is superior to e-glass (ULS). Stats are available here...    http://www.gordoncomposites.com/products.htm   Unfortunately, S-glass isn't available in a good clear form. The natural that is available in s-glass is rather cloudy, so I use S-glass when I use black and e-glass when I use clear. Both are excellent, but s-glass does have a slight edge.

Carbon foam core certainly is already proven in performance, but it is also showing some concerns in terms of durability.

Also, when it comes to wood cores and durability, I would NOT confuse hardness with durability. Toughness = durability, but there are many hard woods that are dense as well...but more prone to crack due to their stiffness. Ebony is one such example. Yes, it is used often and used successfully, but it isn't near as durable as many other woods.

Also, I have shot some bows with osage in them that are certainly tough, but due to the limb mass it isn't my preference for a limb wood as I can feel more shock from it in some bow designs than other wood choices.

Again, these are just my opinions based upon my experiences.

Great! Thanks very much for the time put into your helpful response!

[Lee Robinson .]

NO problem. You know...many people have said that the core doesn't matter, but there are several reasons that I can't accept that.

Not only the "flex" test mentioned above, but also let's discuss carbon. When a bowyer puts carbon in a bow (under the back side glass where its tension strength is allowed to perform), I have to use considerably less core to obtain the same poundage.

For example...if I had two bows one with carbon and one without, the carbon bow would have about 0.0030" less total core (the exact amount may vary depending upon pull weight, draw length, and bow length). Meaning, 0.030" of carbon replaces about 0.060" of wood or bamboo. Now, if one put the carbon in the center of the limb's core its contribution isn't as great. Why? Well...because of its very high tension strength, so it should be used on the tension side (I use it directly under the back glass to protect it).

My point is, when we select what materials go into a limb, I believe it is best to use materials with good tension strength on the back side and good compression strength on the belly. I feel the use of carbon proves this, even though it is a synthetic.

[Sixby]

I agree with everything Lee has said. I especially agree that core does make a difference and I say that from extensively testing it. I also agree on his choices of core woods but add Zebra as my top choice.
Here is what I look for in core wood. A wood that is extremely light but very strong , stiff , holds together instead of splitting and evenly bends with no knots or weird grain runouts. The action woods accomplish this by their very nature but even then there are great variences. For instance Action Maple and Actionboo have very different charistics. Maple is much , Much tougher but on the pull and on the shot boo is much softer in feel. Thereforein many of my bow designs I incorporate both Using them in the stack where they are most beneficial to their character.
 The thicker the core , as in longbows, the more difference it makes. But, it still makes a difference in recurves. There is a lot more to building a good bow than slapping two pieces of glass over whatever. The tension , compression , stiffness, torsional strength and durability qualities of the whatever makes a of difference.

God bless everyone and have a great New Year, Steve

[Kenneth]

Very interesting reading.  Lee and Steve, what would your ideal limbs on a longbow be comprised of (Core, belly, back) for performance not looks?  This is something I've been thinking a lot about and I'm glad I found this thread.

[gobblegrunter]

Originally posted by Kenneth:
Very interesting reading.  Lee and Steve, what would your ideal limbs on a longbow be comprised of (Core, belly, back) for performance not looks?  This is something I've been thinking a lot about and I'm glad I found this thread.

Good question.    

[Lee Robinson .]

Even though bubinga isn't the prettiest wood in the world, nearly all of my personal bows have risers made of it, as it is nearly bomb proof. It has EXCELLENT physical mass, excellent compressive Strength, excellent bending Strength, excellent stiffness, and excellent hardness. It is the perfect riser wood. Check out the specs here on bubinga (scroll down after you click on the link).         http://workshopcompanion.com/KnowHow/Design/Nature_of_Wood/3_Wood_Strength/3_Wood_Strength.htm          

The only thing that is comparable is hickory, and bubinga even has that beat. Also notice in that particular chart there is one wood that beats bubinga in hardness...but as I mentioned earlier if you look at the other scores you will see hardness does NOT mean strength, as that "hard" wood doesn't have near the strength that bubinga has. Many hard woods do indeed crack.  

For what its worth, when Gary Sentman set the world record back in 1976, HH archery and company built a bow of bamboo and it broke. They made another of maple, it too broke. The bow that was the world record bow was actually made of 5 lams of straight grain hickory. That one held together. That stuff is tough, but it has a lot more mass than most people would want in a bow's limb (of course that didn't matter for a world record bow). I only mention it as a testament of what those numbers in the link above mean in terms of DURABILITY.

For my "ideal" bow, my riser would actually be "figured" bubinga with phenolic lamination reinforcement in the grip/sight window section of the riser. The limbs would be 0.030" s-glass (ULZ) on the back with 0.030" of carbon DIRECTLY under the glass. Then my core woods would be bamboo on the tension side (back side of the core) followed with either edge grain red elm (or edge grain maple...as both elm and maple are excellent). The belly would be clear 0.050" e-glass (ULS).

This would be for a bow over 52#@28." If I was interested in a bow 50# or less at 28" I would likely use 0.040" glass on the belly side.

That is my ultimate longbow. I will post some photos of it when I get some new pictures.

Now, all that said...for those that like osage, if I ever used it in a bow it would ONLY be on the belly side and even then I wouldn't use a piece over 0.050" thick in a personal bow. Too much mass to let it get into the "neutral" shear zone or tension zone of the core,  but I think it is fine to use 0.050" on the compression side as long as they use a piece thin enough to keep it in the compression zone...as one might actually get enough compression strength out of it to justify its use there. Many moons ago, Randy (from Saxon Archery) told me that when he used osage on the belly he would get the same pull weight with less core as an alternative lighter wood/grass that flexes easier. I want to do some testing with this, as  it makes sense, but I have yet to test it myself in my own design. If that holds true, then despite its additional mass, one might be able to use less of it in the compression zone and end up with a final limb mass no heavier than an alternate lighter wood that lacks osage's compression strength. Personally, I know I do NOT like bows that are all osage limbs, but that is another ball game, as osage is famous for compression, so why someone would use it on the tension side is beyond me (given there are other choices that have better tension strength to weight ratio). However, a single belly veneer may be acceptable as that would be using the wood's attributes in a manner most productive...and its strength to weight ratio on the compression side may be high enough to justify its use there. For specs on this, check out this link...   http://chestofbooks.com/home-improvement/woodworking/Mechanical-Properties-of-Wood/Compressive-Or-Crushing-Strength.html

[Kenneth]

Originally posted by Protege Longbows:
For my "ideal" bow, my riser would actually be "figured" bubinga with phenolic lamination reinforcement in the grip/sight window section of the riser. The limbs would be 0.030" s-glass (ULZ) on the back with 0.030" of carbon DIRECTLY under the glass. Then my core woods would be bamboo on the tension side (back side of the core) followed with either edge grain red elm (or edge grain maple...as both elm and maple are excellent). The belly would be clear 0.050" e-glass (ULS).

This would be for a bow over 52#@28." If I was interested in a bow 50# or less at 28" I would likely use 0.040" glass on the belly side.

That is my ultimate longbow. I will post some photos of it when I get some new pictures.

Very interesting!  I was thinking along the same lines except without the carbon, and I thought the boo as a core, maple on the belly, and elm for the back.  Also I thought of Cocobola for the riser.  How does flat cut elm with the nice grain showing compare to the edge grain?