Shooting Sports > Archery

Tinkering with another bow design

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Rancid Crabtree:
I?m contemplating designing/building a different version of a bow .  Ive killed deer with a variety of bows over the years and bore easily. A recent bill affecting bowhunting in WI finally created a statutory definition of what a bow is for the purposes of hunting. Until then, the only definition of what a bow is resided in administrative code. The statue that defines what a bow is for the purposes of hunting reads as follows.

29.001(17) " Bow ," when used with reference to hunting, means a bow , drawn and held by and through the effort of the person releasing it, but does not include a crossbow.

While vague, this legal definition allows for a variety of bow construction. Since I hope to design/build a bow that is legal for hunting I contacted the DNR seeking input on what I am planning. As I currently have it designed, my bow is going to be made from  almost conventional materials and methods and currently I plan to build it from
a treated 2 x 4
an old drawer front
tooth brush
dry wall joint tape
glues
rubber bands
wood screws
a short bow string
and other various and sundry items from the local hardware store.

WI laws stipulates that for hunting, a bow must have a minimum of 30 pounds of draw weight. Its my hope to build this bow with about 40 pounds of draw. As it was initially designed, the bow did not have any limbs (but then the legal definition does not include such a requirement so that should not be an issue).

Not looking to create ways to get in trouble with the DNR I enquired with the DNR as to the legality of such a design. I was told that because the design did not have limbs that ?bow?, that it is not a legal bow for hunting. While the state statute says nothing about limbs it does include the word ?bow? as part of the definition of the word bow. the email I received from the DNR did include a copy/paste from the Merriam Webster online dictionary.

Webster

1a : something bent into a simple curve

2a :  weapon that is made of a strip of flexible material (as wood) with a cord connecting the two ends and holding the strip bent and that is used to propel an arrow

While I see no legal requirement to change the design, I changed it after reading that email to incorporate flexible/bending limbs that ?bow? and made sure to have a cord connecting the two ends of the limbs. The current design now meets Webster?s definition as well as WI statute (since state statute say ?Bow means ANY bow????????..?) and this design certainly meets all the definitions and falls under ?ANY? bow.  This will satisfy the state and Mr. Webster.

This design will use a conventional fletched arrow of normal length as well as using a conventional broadhead and will be drawn and held solely by and through the effort of the person releasing it. I?ve built a few bows in my time. My first was back in 1988. This is not like those other bows. Not having tried such a method I know not what to expect or if it will even work. Even if it doesn?t work I will have discovered a new way NOT to make a bow and there is always something to be learned from attempting and not succeeding. My favorite  quote comes from Thomas Edison. On being asked how he felt about repeatedly failing to design a working light bulb Edison said

"I have not failed. I've just found 10,000 ways that won't work"       Thomas Edison

He also said:

?Results? Why, man, I have gotten lots of results! If I find 10,000 ways something won't work, I haven't failed. I am not discouraged, because every wrong attempt discarded is often a step forward....   Thomas Edison

Never be afraid to fail. Failing to try is a far worse fate.      Me

The ultimate goal here is to devise a contraption ( that is not currently a hunting bow used in my home state) capable of delivering a broadhead tipped arrow with sufficient energy to quickly dispatch a white-tailed deer and to do so by crafting it with inexpensive and easily attainable materials. (for perhaps less than $20)

Since this first attempt is a low fidelity prototype which will hopefully lead to a more refined final design, by its very nature, it will be somewhat crude and unpolished. Its my intension to catalog my attempts with this thread.  My oldest son Lives upstate and my youngest is in the army. I?d like to think I?ve passed along the tinkerers urge in them although they are too busy starting out and establishing themselves to demonstrate if it has stuck. Perhaps this and other follies I pass along on the web will inspire others whom I?ve never met. If so, good.  These are two more of my favorite quotes form Edison.

?If parents pass enthusiasm and creativity along to their children, they will leave them an estate of incalculable value....

?I have far more respect for the person with a single idea who gets there than for the person with a thousand ideas who does nothing....?

So even if I don?t succeed, it wont be for nothing and I will have surely learned something I can use in the future meaning it wont have been a wasted effort. After all, the joy is in the doing.

Rancid Crabtree:
Enough of lofty ideals and high mindedness. Time to start doing. A bow needs a handle. Having recently completed a tower deer stand for my father I find myself with a tremendous wealth of scrap pieces of treated 2 x 4 lumber. This handle does not need to be treated lumber but since I am buried in scrap treated lumber, finding uses for it seemed the thing to do.


I plan to launch the arrow through the center of the riser. I drilled holes in a few pieces of 2 x 4 and then glued them together.



Once dry, I did a little shaping with a saw and belt sander to get to this crude shape.





I?ll set that aside for now to work on the limbs. I have an old hard rock maple drawer front that been moving around my shop for a few years waiting its turn to be used. I will use that drawer front to make laminations for the limbs.



Not really sure how many laminations I need. I guessed at 4. The laminations will be held together with epoxy and will be faced and backed with drywall joint tape in lieu of fiberglass.



The limbs will be straight with no curve so I don?t need to build a form. A scrap of lumber and  many clams will suffice.



Once cured, I can continue. Edison said that "Genius is one percent inspiration, ninety-nine percent perspiration" While don?t claim genius in this project, with temps near 100F today, I think I met the required levels of perspiration. Luckily is not colder out or I would have to think more.

Rancid Crabtree:
With the limbs cured, I unclamped them and sanded the rough edges. The drywall tape rests beneath the epoxy. From the side you can see the thin glue lines.





Here is a pair of limbs cut from the long limb I glued up. I tapered them and drilled mounting holes as well as rounding the edges nearest the arrow rest opening. Aside from the screws, I hope to use the arrow rest to capture the limbs. As you can see, the limbs are very short, somewhere in the neighborhood of 8 inches.



At the tips I filed groves as you would expect to see on limb tips.



Here are the limbs mounted to the riser.



Now its time to make an arrow rest.

Rancid Crabtree:
Its been too hot to work in the shop so the wife and I took a few days and headed up to the cabin over the 4th. While still pretty warm out at least its in the low 90?s and upper 80?s rather that 100+F.  I went to the Dollar store and bought a pack of Tooth brushes for this bow.



Then I cut them down saving the usable portion.



Then I made a holder for them out of scrap wood and attached the brushes with epoxy and wood spacers. I drilled the block so it can be attached to the riser.



The back side is cut out to receive the limbs.




Here is the arrow rest attached to the riser with screws.



The next step was to make a bow string. Nothing fancy, I just made a simple 18 stand string.



As time allows, I will work on adding the other parts and putting it together.

Rancid Crabtree:
As I stated in the opening post, one of the components of this bow would be rubber bands. In this case, physical therapy rubber bands.



I cut a bunch of tapered bands, wider at the point where they will be attached to the limbs and narrower where they attach to the bow string.



Not knowing how many bands would be required to achieve 40 pounds of draw, I cut a lot.



I guessed at 3 bands per limb and got 30 pounds. I added a fourth band and hit 40 pounds right on the head when I drew the bow back to a 28 inch draw length. Here is the rough assembly to establish draw weight.









There is plenty of tinkering left to make this thing manageable in terms of draw and hold before I can even consider sending an arrow through it. After drawing it with my fingers, its clear the string angle is too steep for fingers in terms of string pinch which will effect comfort and a smooth release. I think I need to tie on a loop and use a release. To be continued???????..

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