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Main Boards => The Bowyer's Bench => Topic started by: coaster500 on January 04, 2011, 09:48:00 AM

Title: Shelf shape ... Design and why?
Post by: coaster500 on January 04, 2011, 09:48:00 AM
I'm curious and in my searches I've haven't satisfied that curiosity.

I posted the same question on PowWow but then thought this might be a better forum.

Now that I have owned and shot a BUNCH of bows of different designs and types, I have a question.

What are the advantages and disadvantages of shelf design? I see some bows with longer flat shelves and some with rounded and some that nearly peak where the arrow rests. I have my opinion and preferences but am more interested in hearing bowyers say?
Title: Re: Shelf shape ... Design and why?
Post by: dcmeckel on January 04, 2011, 10:04:00 AM
I have been told that a shelf with an upward radius to it,having the height of the arc above,or very close to,the deepest part in the throat of the grip,is best for most shooters.
On the older Bear bows that I owned,I would simply place a thin piece of leather under the shelf plate,right above the throat.Seems to work for me.
Title: Re: Shelf shape ... Design and why?
Post by: KellyG on January 04, 2011, 10:05:00 AM
Coaster500,
I am currently reading the bowhunters hand book, and it give simple explanation on shelves' and rest. What I gathered is that the more center shot a bow is the less finicky it is to spine of the arrow.  Now the trade off the more center you make it the more wood need to keep it from breaking longer and thinker handle areas. Plus the time in making such bows. If you make a shoot off the hand bow not as much in making the bow if you add even a simple rest and so forth.
As for the shape I think it is more appearances the less contact with the self/rest the better. This is all that I have learned thus far and it makes since. I know others with h more knowledge will pipe in.
Kelly
Title: Re: Shelf shape ... Design and why?
Post by: Swissbow on January 04, 2011, 12:07:00 PM
In my opinion the shelf should be rounded in an upward radius and the peak of this radius should above the pressure point on the grip. On a recurve that means the deepest part of the throat ( like mentioned above ) and on a longbow that means above the spot where your palm applies the pressure on the grip. The reason for that is, that this helps to compensate/eliminate the influence of a bow that is not aligned correct and slightly tilted to the left or right in the bow hand.

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Andy
Title: Re: Shelf shape ... Design and why?
Post by: Loren Holland on January 04, 2011, 12:58:00 PM
i read that a radiused shelf has less contact, with the arrow, and less intereference for lack of a better word.  I cut mine radiused slightly forward, I also slope the shelf towards the center slighty (I saw one of Bob Sarrels bows cut that way and liked it so much i tried it too). this arrangement helps keep the arrow on the shelf, but still promotes accuracy.

to make cutting shelves easier, i do my initial cuts with a band saw, and then use a dremel took after that. for the most bite i use a grout cutting bit, then move up to a sanding wheel.
Title: Re: Shelf shape ... Design and why?
Post by: Swissbow on January 04, 2011, 01:42:00 PM
Sorry, forgot to mention that the sight window also should have a slight radius and it's peak should be at the same place as the one on the shelf.

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Andy
Title: Re: Shelf shape ... Design and why?
Post by: dcmeckel on January 04, 2011, 02:20:00 PM
Andy is right,and if at all possible,line up the high spot in the window,the one on the shelf,and the throat of the grip.
Title: Re: Shelf shape ... Design and why?
Post by: coaster500 on January 04, 2011, 07:25:00 PM
From just the logical view all of the above reinforces my thoughts, so why do some bowyers still produce bows with a flat shelf or to my eye it seems so?
Title: Re: Shelf shape ... Design and why?
Post by: red hill on January 04, 2011, 07:39:00 PM
On the few bows I've made the radiused shelf seems to be best... At least for me.  I tried the flat shelf but accuracy suffered.  The flat shelf was on the first couple of bows I made and were easier to fashion.  The radiused shelves have helped improve accuracy and have a more appealing appearance.
JMO,
Stan
Title: Re: Shelf shape ... Design and why?
Post by: kennym on January 04, 2011, 09:55:00 PM
I agree, radius shelf and side plate.

My bows have been getting a slight peak on shelf over the grip,harder to do on a longbow without much behind the low part of grip.
Title: Re: Shelf shape ... Design and why?
Post by: monterey on January 05, 2011, 01:07:00 AM
Redhill, I agree especially on the flat shelf situation.  If a shelf is flat, especially on a recurve with a lot of depth in the riser, and is at 90 deg to the string, then your arrow will end up resting on the edge of the shelf at the back side of the bow.  This is the case with several old Shakespeares, Martins and Pearson bows I have (or had).  I know some guys who have taken a rasp and sandpaper to these type of sight windows and improved them considerably.

Swissbow explained it well IMO.  The double radius above the bow hand pressure point also helps eliminate the effects of the riser twisting from being gripped too tightly or unevenly by the bow hand.
Title: Re: Shelf shape ... Design and why?
Post by: bamboo on January 05, 2011, 02:05:00 PM
the arrow isn't touching the shelf for very long after the release on the high speed film i've seen--although i do like a radius shelf myself
Title: Re: Shelf shape ... Design and why?
Post by: ChristopherO on January 05, 2011, 02:06:00 PM
Coaster, the reason the factory's made shelves flat was purely economical.  It is much easier to mass produce a bow with a flat shelf compared to a radius shelf and sight window model.  
I just finished up another recurve riser this past weekend and the time involved for this proceedure is considerable.  In years past all details that incorporated unnecessary hand filing and sanding were regulated to the custom shop/extra cost catagory.  Now days a company with CNC machines could make quick work out of this custom feature so there really isn't any reason a lager, well equipted shop would continue the flat shelf/flat sight window design.
At least a stick on arrow holder can be applied to that design.
Title: Re: Shelf shape ... Design and why?
Post by: JamesV on January 06, 2011, 10:28:00 AM
I think a radiused shelf and sight window are a help but not a cure-all. If the bow is tillered right and the shooter has good form it is not as important with the right arrow. But who has all that???? I hunt with a kodiak Mag and it has a flat shelf and window, never checked the tiller but I think Fred got it right and my form.............well.......... but it shoots where I look with good arrow flight. I do radius all my bows and most are cut to center.

                        James............
Title: Re: Shelf shape ... Design and why?
Post by: coaster500 on January 10, 2011, 10:19:00 AM
Thanks guys, it's nice to hear from the experts  :)