helical ?
01-05-2003, 05:54 PM
#3
Nontypical Buck
Join Date: Feb 2003
Location: Altmar New York USA
Posts: 1,247
RE: helical ?
From what I've read, and learned on this sight, mags, internet. There's no reason to be shooting straight fletchings accept where rest clearance is a problem. You should be shooting some sort of offset-helical. The more the better. The sooner, and more spin you can put on your arrow the more accurate it should fly. I started many yrs ago with some pre-fletched straight vanes. When I began doing my own, and used a right helical I couldn't believe the difference!
01-06-2003, 02:35 AM
#4
Dominant Buck
Join Date: Feb 2003
Location: Blossvale, New York
Posts: 21,199
RE: helical ?
I've been an advocate of straight fletch for years. Well, when I went to a little faster setup with lighter arrows I had to work harder to get broadheads tuned. I'd start with a dozen arrows and end up with anywhere from 6-8 that I called hunters. I'm picky. If it doesn't shoot like a field point I don't use it. The last couple times I had arrows fletched I put in a little helical. Not much, just a little. It sure has helped my arrow flight.
01-06-2003, 12:34 PM
#5
Join Date: Feb 2003
Location: Clarksburg Wv USA
Posts: 33
RE: helical ?
I have always shot straight fletch also, but am considering going to helical. Really didn't have a whole of problems with straight but could probably be better. How much helical would one need with a Whisher Biscuit ?
01-07-2003, 02:35 AM
#7
Join Date: Feb 2003
Location: Vermilion Ohio
Posts: 183
RE: helical ?
years ago i use to have problems tuning broadheads....then i started watching some hunting videos. you know the ones that replayed the shot 2 and 3 times in slowmo. well i noticed during the slowmo's that no one shot a straight fletch. i said to myself "hummmm maybe they're on to something here", so i switched to helical fletch for hunting and haven't had a problem since. i'm convinced that i could shoot a fixed blade broadhead w/a 12" cutting radius and make it fly using a helical fletch on my arrow. <img src=icon_smile_big.gif border=0 align=middle>
01-07-2003, 10:58 AM
#9
Join Date: Feb 2003
Location: Baltimore Maryland USA
Posts: 1,385
RE: helical ?
This subject recently came up on another forum and the person posting the thread asked: "Can someone tell me if i can shoot broadheads using straight vanes, or if i need to replace them with helical ones...". The answer is 'yes', you can shoot broadheads using straight vanes - that is, IF your bow is exceptionally well-tuned.
In my shop we always tune to straight fletching and then offer the customer whatever style of fletching he/she desires. The tuning of a bow with helical puts a 'bandaid' into the system that may have a corrective action before you really identify the real problems. If your bow is tuned finely with straight fletching, and then you desire to go to an offset or helical, you much further ahead in the confidence and forgiveness areas.
Another poster entered into the conversation on the other forum with a statement about wind affecting arrow flight and how helical would correct this problem. My response was: "As far as wind is concerned, any object will drift with the air flow/current. Airplanes, in order to arrive at a specific destination, sometimes have to fly many degrees off a straight line to counter the wind. Arrows cannot make 'in-flight' course changes; therefore, no amount of helical will really correct for a crosswind."
Another poster brought up the comparison between rifle rifling and arrow spinning. His question was: "If straight fletching is perfectly acceptable... wht then did rifles get away from smoothbore and go to "rifling"???
Simple... it still stabilizes the projectile.
End of story.."
Well, that wasn't really the "End of story.." I responded with: "The ratio of diameter to length of a bullet is QUITE a bit different than that of an arrow. The spin put to a bullet is to attempt to keep it from tumbling. We're also talking about something that travels over a much longer distance at a much greater speed when referring to bullets.
If analogies are to be used, I think we should compare the arrow to a spear (such as those used in the Olympics). If helical fletchings made that much difference on an arrow. why not use them on a spear, which has similar diameter to length characteristics?
Keep in mind that I believe helical fletchings can be helpful; but, I try not to use helical as a cure to insufficient tuning."
Then a poster named "hickock" (USAF) enter the thread with this authoritaritive response: "Okay back to the real question.......the spin induced on the arrow is beneficial always. what it does is insure that no abnormality in weight...glue....or what ever stays on one side of the projectile where it will be allowed to pull it off course....it spins the abnormality and ensures it cancels it's own self out....It shouln't be compaired to the rifling of a bullet because the rifling of a bullet will enduce a centrifical force that will stabilize the bullet like a gyro......arrows won't spin fast enough for this.
The interesting thing about helical fletching with broadheads is that you can induce barrel rolls.....where a particular head attempts to plane but the arrow's spin pulls it around and the result is a nauseating barrel roll towards the target resulting in complete unpredictability."
My final response was: "hickock: Thank you for that clarification. Helical was originally done for wooden arrows to do just what you stated - "....it spins the abnormality and ensures it cancels it's own self out....". Wooden arrows were not straight and had many abnormalities in their design.
I look at the helical more as a drag coefficient rather than a spin characteristic. Too many try to correlate the spinning arrow to the spinning bullet."
While you have my comments/feelings on the subject, I believe it is in the best interest of the sport to get other points of view and to relate them. I hope all this helps.
In my shop we always tune to straight fletching and then offer the customer whatever style of fletching he/she desires. The tuning of a bow with helical puts a 'bandaid' into the system that may have a corrective action before you really identify the real problems. If your bow is tuned finely with straight fletching, and then you desire to go to an offset or helical, you much further ahead in the confidence and forgiveness areas.
Another poster entered into the conversation on the other forum with a statement about wind affecting arrow flight and how helical would correct this problem. My response was: "As far as wind is concerned, any object will drift with the air flow/current. Airplanes, in order to arrive at a specific destination, sometimes have to fly many degrees off a straight line to counter the wind. Arrows cannot make 'in-flight' course changes; therefore, no amount of helical will really correct for a crosswind."
Another poster brought up the comparison between rifle rifling and arrow spinning. His question was: "If straight fletching is perfectly acceptable... wht then did rifles get away from smoothbore and go to "rifling"???
Simple... it still stabilizes the projectile.
End of story.."
Well, that wasn't really the "End of story.." I responded with: "The ratio of diameter to length of a bullet is QUITE a bit different than that of an arrow. The spin put to a bullet is to attempt to keep it from tumbling. We're also talking about something that travels over a much longer distance at a much greater speed when referring to bullets.
If analogies are to be used, I think we should compare the arrow to a spear (such as those used in the Olympics). If helical fletchings made that much difference on an arrow. why not use them on a spear, which has similar diameter to length characteristics?
Keep in mind that I believe helical fletchings can be helpful; but, I try not to use helical as a cure to insufficient tuning."
Then a poster named "hickock" (USAF) enter the thread with this authoritaritive response: "Okay back to the real question.......the spin induced on the arrow is beneficial always. what it does is insure that no abnormality in weight...glue....or what ever stays on one side of the projectile where it will be allowed to pull it off course....it spins the abnormality and ensures it cancels it's own self out....It shouln't be compaired to the rifling of a bullet because the rifling of a bullet will enduce a centrifical force that will stabilize the bullet like a gyro......arrows won't spin fast enough for this.
The interesting thing about helical fletching with broadheads is that you can induce barrel rolls.....where a particular head attempts to plane but the arrow's spin pulls it around and the result is a nauseating barrel roll towards the target resulting in complete unpredictability."
My final response was: "hickock: Thank you for that clarification. Helical was originally done for wooden arrows to do just what you stated - "....it spins the abnormality and ensures it cancels it's own self out....". Wooden arrows were not straight and had many abnormalities in their design.
I look at the helical more as a drag coefficient rather than a spin characteristic. Too many try to correlate the spinning arrow to the spinning bullet."
While you have my comments/feelings on the subject, I believe it is in the best interest of the sport to get other points of view and to relate them. I hope all this helps.