Build Along ( building by mass)

[tom sawyer]

That first bow I posted was also osage.  And I honestly don't find the second bow to have hand shock at all.  Thats a subjective thing though.

[Marc St Louis]

Some people figure the formula is good for begainers but I actualy think it is more for advanced work.

You're probably right Steve. A lot of guys that have been making bows for many years are satisfied with the bows they make even though they no doubt can be improved on. Beginners are the ones more likely to use the formula though and in so doing make huge improvements in their bows mainly because they have no preconceived notions and are starting out with an open mind.

[jwillis]

Marc, you said a mouthful.  As a beginning primitive bow maker, I agree 100%.  You guys who have made many, many bows from many different woods have an advantage.  I've only made one selfbow, so I have no preconceived notion, except from my many years of making glass bows.  Big difference.  To be honest about it, I'm also looking at the mass formula from the perspective of improving my glass designs.  Many glass bow makers including myself often get bailed out on a bad design due to the forgiveness and strength of the glass.  I'm trying to overcome that.  A good bow is a good bow...lol.  Jim

[mullet]

  Can you imagine all the knowledge of bow makeing that could have been shared 10 years ago without the internet.

[Badger]

I think the internet has given us 10,000 years of advancement in bowmaking. One thing I laugh about a lot. If joe shmo has a great idea about bow making and shares it with us online within one week the whole world knows whay he knows. A lot of guys are just blessed with a natural feel for the art of bow bowmaking. Before the internet I htought I was the only one in the world who made wooden bows, I struggled like crazy for a few years.  2 weeks after I got online I was making bows that worked. Jim, I think it is really cool that glass bowyers and wood bowyers have started sharing design ideas, I imagine when glass firt came out they did the same thing and then went seperate ways. Everything went to glass recurves. The long bow is making a big time come back in traditional archery. Both modern and primitive. Good stuff happening right now. Steve

[Badger]

I am actualy working on another one right now, this time an elb, I glued it up this morning and will clean it up tomorrrow and start tillering. The only two set ctiterias I have are draw length and bow length. I am going to let mass dictate the tiller and the poundage. I will do it as a buildalong. It is bamboo, maple core and mora belly. The raw glue-up weighed 30 oz, belly is allready rounded, tomorrow I will shape it like an elb and clean it up and I imagine the weight will drop to about 25 oz and from that point I will see where it steers me. An 80# elb with a semi stiff handle section should come in around 22 oz, this will likely be what I go for. Steve

[George Tsoukalas]

"Daddy, all your bows look the same." That's what my daughter said once. LOL. I always tried to involve my daughters in bow making for various reasons. I guess I'm not that open minded regarding trying different things.   Jawge

[Badger]

Jawge, you are like a rock in our bow building community. You show people how to build good solid bows using sound proven principles. Ane then you have that science background behind you to seperate the bs from the good stuff. Good mix! Steve

[George Tsoukalas]

Thanks, Steve, for the kind words. Jawge

[Keenan]

 Great info Steve, Thanks for sharing.   You are definately the one that knows the threshold of what bow wood can take and design concepts for performance. Most will build a bow leaving alot of excess wood and stay very safe with overbuilding. But you seem to love coaxing every once of performance that a bow can give. I'm sure that you've pushed the limits beyond the breaking point more then any can count, but because of that you've learned the limits.     Keenan

[jwillis]

"I am going to let mass dictate the tiller and the poundage."

Steve, can you explain how you are going to do this?  I usually remove wood to obtain a certain cross sectional shape or profile or arc on the tiller board.  Are you just saying that you are going to do this down to the target mass and see what the draw weight ends up at?  Jim

[Badger]

Jim, good question, thats one of the reasons I am doing a build along or possibly several of them is to hopefully see what kind of questions come up. What might seem clear to me might be really confusing to someone else not familair with it.
   Ok on this elb I am working on now. I randomly selected a demension of 72" long and 1 1/8 wide at the handle. An elb has certain guidlines it has to meet, The belly need to be rounded starting from the back and it also has to meet a 5/8 rule of thickness, meaning the thickness cannot be less than 5/8 of the width. On this particular bow I simply glued it together, and then this morning I went out and just ground it out on the belt sander to meet the 5/8 rule and got the tiller pretty close with no pre determination on draw weight. ( i will post pics in about an hour) anyway after cleaning the bow up and re weighing it I find the bow weighs 22 oz. A boo backed bow can easily go about 10% less than what the calculator spits out so I go from there. I know now that after final tillering the bow will come in around 20 oz. I simply go back to my calculator and feed some numbers into it to see what poundage, draw length and tiller style would best fit this bow. Elbs have 3 basic designs a sporting tiller, a flight tiller and a war bow tiller. ( elb enthusiasts correct me here if I am wrong) If I use a war bow tiller for instance I would feed numbers in that allow for an arc of the circle tiller. This would be a 0 for stiff handle and fade area and would have a full working handle. The warbow tiller would allow me to build about a 100# bow from this stave and draw it to 30".  If I decided on the sporting tiller I would leave the center 8" on the stiff side although they would still have some flex so i would use a 4" figure for stiff handle and fades and this would allow me about an 80# bow for 20 oz.  Now if I choose a flight tiller I would keep the center 16" on the stiff side but still flexing so I would use an 8" figure for stiff handle and fades and this would allow me about a 70# bow at 28". Nothing has to be exact here but the formula is giving me a good idea of what I have to work with. I don't have to have any knowledge of this wood as long as I know it is true bow wood to carry out these designs and feel certain of a good performing safe bow. Now it just so happens that I do have some prior experience with this particular specimen of wood and I know it can be pushed safely a little beyond what the formula calls for. So I will actually go for something inbetween the sporting and the flight tiller and look for a finish draw weight of about 80# and a mass weight of 20 oz, possibly 19 oz if I feel lucky. Steve

[Badger]

Here are a couple of pics, floor tillered and front view, Today i will glue on some overlays which can be removed later for horn nock replacement. Tomorrow hopefully I can tiller it out.

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[Badger]

One thing i want to mention is that I am doing these bows a little faster than I notmaly would and the tillers won't likely be perfect. some guys have a natural eye for tiller and some guys like me can spend a month tillering something and it still won't be perfect anyway LOL. Sometimes it seems like the longer I screw with something the worse I make it. The bow in the pics has about 1/2" reflex glued into it and will hopefully finish out with about 1" of follow or less. Steve

[Badger]

Maybe a little discussion on the different tiller shapes for elb would be in order right now. I would guess that a sporting tiller is primarily used for lighter weight elbs that one might use for target or weekend clout shooting for instance. Just by the nature of the design of an elb they are allready so narrow that it would be hard to make them narrower for a lighter weight bow. The only real logical way to make them with a lighter draw weight is to just tiller so the outside limbs are moving more and the center of the bow is moving less otherwise there simply wont be enough stored energy to effectively swing that long working limb, if you went narrower they would become lateraly unstable. Using woods with different specific gravities more tailored toward the draw weight and length of the bow you will be shooting can help effectively give you the desired tiller shape, otherwise the mass formula can suggest how to tiller for a specific draw weight based on how much wood you have to work with. Steve