Some "No Glass" Information....

[badger5149]

The one thing I like about the wood bows is the same thing that makes me hate the wood bows. When we look at bows in general throughout history we see quite a few radicaly different designs. The asiatic horn bows, the english long bows, the indian bows etc. The one thing these bows have in common is that htey were optimized to work with the materials that they were using. All of them perform close to the same when made right. Trying to make a wood bow look lke a horn bow to me is a waste of time, it will work and give decent results but is taking the long way around for not the best results. When working with wood only we find that there are differences between the species of wood. Most of them behave similar but if we are trying to optimize something we want to get as familiar as possible with the best design for a specific species. Kind of like being married, it might take a few years to figure out how to push that womans buttons just right and if you change women you have to start over and figure it out again. Some of the fastest woods are also the most tempermental, brazilan cherry, purple heart, locust and a few other were emntioned, all of these can make excelent bows and are extremely fast but also prone to cyrsaling. This just means they need a design that suits them. Other woods like osage and yew have a lot of elasticity and can handle much more radical designs. I have found I can get best results out of woods like maple just because it seems to agree with the designs I like to use.
I really believe that one of the secrets to wood bowyering is to establish tecniques that will allow you to monitor the condition of the wood as the build on a bow progresses. When a bow is layed out and glued up it has an optimum draw weight and draw length, hopefully it will be exactly what we are targeting but it seldom is. By over building the raw bow and then honing in on it's optimum features I think we can get closer. When I am talking about the conditon of the wood I am simply reffereing to the wood being in the same condition it was before we started bending it. A perfect bow would have no memory of ever having been bent. Until a couple of years ago I had no idea of how much I was damaging a bow before I ever even got a string on it. I had no way to monitor it. Once you learn how to monitor the wood making adjustments starts to become like second nature.
The first step in monitoring is simply to know how much effort it takes to pull a bow so far. You have your bow roughed out and it is starting to flex a bit when you push it to the floor. Put a string on the bow that is about the same length as the bow, just so it doesn't hang loose to much. Now pull it down about 6" or so and see what your scale reads. lets say it reads 10#. make a note of that and 6" @10# will be your benchmark for now. Pull it to 7" and then go back and make sure it still reads the same at 6". Now go to 8", 9" 10" each time going back to 6" making sure there has been no change. If you notice a slight change then you need to get more limb working as it is starting to show excess strain. Each time you remove wood you will need to establish a new bench mark, always make your new benchmark the furthest place you have drawn it so far. Once you start getting close to full draw and you see the bow has not shown signs of strain you might want to start removing wood from the sides to lower the draw weight, any time it shows a slight sign of strain then you want to remove wood from the belly. If you can succeed in getting a bow to full draw with no loss of weight due to strain you will be amazed at fast they shoot. many times I have cut a bow out to what I would figure to be normal demensions for a 50# bow only to find out 40# was the most I could get out of it without breaking it down a bit. It is kind of a fun excersize to try and really enhances the pucker factor part of making bows. Steve

[Hornseeker]

Steve... would I love to watch you build a bow or two... dammmm...

Hey..do you think my 3/16 inch paduk stripe is what probably failed me, being between ipe and boo?? I sure think so, but cant tell...

So have you built a bow lately?

Ernie

[jwillis]

Steve, that is probably one of the best bow making how-to's I've ever read.

Ernie, did you show a pic of this?

Jim

[forn man]

Steve, I agree. That was a great post.

I have been studying your work for a while now. I currently have a boo backed ipe bow glued up and roughed in. I've been thinking about using this "side tillering" method, but have been reluctant to do so without learning some more specifics.

If I understand you correctly, if you notice that a bow is "showing signs of strain," that is, dropping on the poundage of your benchmark, you should engage more of the limb by tillering on the belly? Remove weight from the sides, and engage more limb from the belly?

I've got a good scale now, and will be planning to use it more during the process.

[HFD60]

Thought I would post a few pic's of my latest bow for you.....It's bamboo backed ipe, 60" oal, 58" ntn, and 55#@ 27". The handle is hickory, shadua, marblewood, and ipe. It's backed with copperhead skins. The string is 10 strands of 8125 with padded loops......

[Kanuck]

HFD60

That is a very, VERY nice bow! I've built a straight limbed bamboo backed ipe with purpleheart riser and tip overlays and I find it nice enough but your R/D ipe/boo/copperhead bow takes the cake!

Have you found that the deflex has increased? Mine has taken quite a set...

Kanuck

[stiknstring]

Thats a David Knight blank if I remember right. I would like copy some of his form measurements to get a similar profile on the next one for me.

[Jesse]

Hfd60 Was that the bow you had down in TN? David makes a nice blank. Tillering out one of his blanks is almost more fun sometimes than building one from scratch.
Badger that was a good explanation of proper tillering. I never used weight as a benchmark before but rather compared the profile before,during, and after construction. Using the benchmark weights would tell you much faster than looking for set only by eye. Thanks Jesse

[HFD60]

Jesse, that is the bow I had in Tenn....

[Hornseeker]

Yeah..that is one purty bow for sure... Seems to have a lot of deflex, but as long as it shoots nice... who cares!!