Materials verse design

[RC]

Ok ,On r/d longbows of the same design everything the same. How much difference in performance will you get from using Bamboo or maybe red elm or osage.Talking lam bows here.Thanks,RC

[RC]

I ment to add that a bowyer told me once that design has the most to do with performance and mat. very little.opinion or fact?RC

[Orion]

Design may have more to do with performance than material, buy you're asking what's the effect if design is kept constant.

In that situation, I think bamboo has an edge over other materials, though I don't have measurements to back it up.  For one, the bamboo is physically lighter so there is less energy wasted moving the mass of the limbs.  IMO, bamboo is also springier and recovers more quickly from being flexed. (That's why it also makes good fly rod material.)  That also leads to a little more energy per pound.  To me, bamboo also feels smoother to draw.  I don't think any of these differences are large.  They probably are measurable, but I don't know of anyone who's done it in a systematic/scientific way.

[Apex Predator]

I haven't noticed much difference Robert.  If using heavy woods for the outer lams, I try to keep them thin in relation to the lighter core lams.  I'm gonna start using thinner glass soon, and expect that's where I will start seeing a difference.

[owlbait]

EVERONE knows that Bamboo makes the difference! I convinced myself of that years ago and I couldn't change my mind now if Dr. Ashby told me it wasn't true  

[mooseman76]

I've shot Black Widow recurves with both the bamboo and birch cores and to be honest I couldn't tell a difference.  I thought the bamboo was smoother, but that turned out to be in my head.  I had them side by side and couldn't tell which I was drawing with my eyes closed.  That said, I've heard that the cores matter more on a thicker longbow limb than on a thin recurve limb.  Best bet is to ask the individual bowyer...Mike

[ONE SHOT]

I use .030" "F" Glass on My Kids Young Youth Bows.
I use .040" "F" Glass on any Bow be it Recurve or Long Bow in the 40#-50# Draw weight range.
I use .050" "F" Glass on all My other Bows.

AS for different wood Laminates it dosen't really make a huge difference. I prefer good old Hard Rock Maple for My cores, all the other Laminations are just for Cosmetic purposes.

Since I cut down My own Trees I have access to Black Locust, REd Elm, Osage, Black Walnut, Hackberry, Mullberry, They all make for vwrypretty Bow Laminations under Clear "F" Glass....ONESHOT...      

[vermonster13]

Maple has been one of the best core materials forever, very durable and consistent(a lot of gold medals have been won with maple cores). Bamboo can be a great core material depending on the bamboo used.

Design is much more important in wood and glass bows.

[longbow1]

I agree with vermonster, design is most important. With that said, I don't shoot anything but bamboo.

[Holm-Made]

I use bamboo for cores because it is a nice material to work with and it comes in 6 foot lengths which is convienant.  I think maple, red elm and others are just as good.  Hard to argue against Maple when you see 50 year old vintage bows still shooting strong today.  
But to answer your question, design is what makes a bow tick.  Chad

[ChristopherO]

With my limited knowledge I look at it this way;  if I can keep my f/g laminated bow strung continuously without fear of loosing draw weigh or causing set then the fiberglass must be doing all the real work.  The wood lams are pretty filler.

[RC]

Thanks Guys. RC

[Canadabowyer]

While design seems to be the most important factor with wood and glass bows,if i build a two longbows excatly the same except use very light limbs in one( like bamboo) and very heavy limbs in the other(like osage) the shooter will find they feel different at the shot.For lack of better words the bamboo will feel smoother and less shockey than the osage. The longer the bow the more this is evident.As the bow gets shorter this becomes less evident. I like my long longbows to have light limb lams and as I get down to about 62" I prefer the heavier woods, mostly because I build the 62" bows to shoot heavy arrows for Moose hunting.   Bob

[RonD]

Bow building is something new to me and haven't had the opportunity to look into the subject. Could you explain what constitutes bow design and how that relates to the materials used in constructing a bow?  Please forgive me ignorance on this subject matter but I am very interested.

[O.L. Adcock]

RonD, That would take volumes and would mostly be subjective at the end anyway!  


Design definately is the biggest factor but that doesn't mean materials aren't an issue. The problem with saying "this is better then that", is the huge variation between the same materials. Take bamboo for example...If you randomly check the density of bamboo lams commonly available, you'll find over 100% variation in density alone. Add in riser stiffness variations and you can see 10% performance differences in the same design....O.L.

[wingnut]

DAng OL said a mouth full there.  Rusty used to tell me when I asked all questions about consistancy of materials or lack there of.

"It's wood DUMMY"

That's why we make all our own lams, we can control the selection process, moisture content and grind.  Get a lot more consistancy when you don't rely on others to make it.

In our bows, the tonkin bamboo core will out perform the maple by 8-12 ft/sec.  Can't speak for other designs.


Mike

[myshootinstinks]

I've shot two bows of the same exact maker / model, using the same arrow, and very similar draw weights,(1 lb diff), side by side.  Checked on a scale, not taken from what is marked on the bow. One being obviously faster than the other.  Logically, design would be the most important factor in bow performance but there is something else going on here. Material? Age? (one bow is 2-3 years older).
 Beats me..... Doug

[amar911]

No one has mentioned foam cores yet, but the material is very consistent, especially along its entire length in a given bow, and it is light too. One might argue that it has not been tested long term like wood, but I am pretty sure it will last me well for as long as I will be shooting a bow, and probably my son too. Bob Morrison says he will personally never shoot a bow that is not foam core unless something new comes along that is better. Now that I have half a dozen foam core bows I can say that I am very pleased with the material, but I still have about 30 wood core bows, and most of them are great shooting bows too. I don't know anything about building bows except from what I have read, from what I have heard from the bowyers who do build them, and from shooting many bows with various materials and designs. From what I have read, heard and observed, I agree that design is much more important than materials, but there can be incremental advantages to the judicious use of the correct materials in a particular design. Just because a good material is used, that does not mean the resulting bow will be better than the bow would be without it. For instance, most bowyers have found it difficult to produce a recurve in poundages below about 60 pounds that has carbon backing on the limbs where that bow is as smooth and forgiving as one that does not have the carbon. That is because those limbs are too thin to be able to get the proper proportion of carbon fiber to core and glass material. As the poundage of the bow gets higher, the limbs get thicker, and then the carbon backing does not overpower the other materials. Because longbow limbs are thicker, but not as wide, as recurve limbs, carbon backing seems to work fine in most designs when the limbs are greater than about 40 pounds or so. Bob Morrison tells me he has experimented a lot with the carbon backing, and he does not recommend it on most of the recurve limbs he produces unless the draw weight gets higher than what the majority of his customers shoot. That is with his limb designs. I think that Black Swan has been successful in using carbon backing and ceramic bellies on recurves of even lighter poundages. David Knipes tells me that Black Swan uses more advanced materials (carbon is not carbon is not carbon) and new designs to achieve the desired results. So, design and materials definitely work together, and the bowyer must understand what materials work with his designs. We are fortunate to have so many good bowyers making great bows that we can shoot.

One comment on the observation that bamboo makes good fly rods. I remember many years ago when the premium rod that Orvis sold was made of bamboo, but anyone who is not at least middle aged can remember that time. Orvis and every other major fly rod manufacturer long ago turned to carbon fiber and other high tech composite materials to make fly rods (and other rods) that are the best performers. Bamboo rods are still some of the most beautiful, but they have mostly gone the way of the dinosaurs. We long ago discovered that various composites enhanced the performance and durability of "traditional" bows. Bamboo may outperform maple in the Dryad bows and may even be as fast as foam cores in the same bow, but with other designs I expect the foam cores to be even faster. There is nothing more beautiful than wooden bows, but we can also get that beauty when we combine advanced composite materials with wood in our bows, and many of today's bowyers do just that. Today's trad bows are the best ever made.

Happy New Year to all!

Allan

[amar911]

Before I get slammed by someone saying that carbon is always the same, please let me say that I am not talking about carbon on an atomic level, I am talking about the properties of carbon embedded  sheets that are used to build bows, fly rods, bicycle frames, aircraft, etc. It is not the same in those varying forms. Remember that diamonds are just carbon too! Sorry, but I wanted to clarify my statement.

Allan

[O.L. Adcock]

Allan, There are some very good bows being made with "foam" cores but the "foam" I've tested isn't "lighter" at all. I think folks assume it's lighter cause they call it foam or because they've hear others say so. It's no lighter then red elm nor have I seen any bow tests to show any advantage at all other then consistancy.....O.L.