FOB flecthing only better!

[gibblewabble]

How do you find time to tune your arrows when you're always on here?
Regardless, I never liked the whisker biscuit, thought they were a piece of crap, still do. I did peruse the FOB web site and I think that there is more merit to the FOB than the whisker biscuit. Each to his own.

I am a still hunter by nature, I have a very hard time sitting for long periods therefore I like the whisker biscuit as it lends itself to my style of hunting. If I just shot 3d I would give em a try but 3d for my is a fun way to get ready for the season, that and my wife likes 3d as well after 12 years of trying she finally got onboard 5 years ago.

[Kirby]

They do weigh alittle more than vanes obviously 24.5 grns to 15grns so it helps to bump your FOC alittle but not much because the FOB actually creates some lift for the back of the arrow.

Sorry, but how do they cause lift??

Kirby

[Slugman]

Sorry, but how do they cause lift??

Kirby

Beacuse the vanes are encircled, this outside ring or structure actually functions as a wing as it pass through the air. The offset of the inner vanes which induce your arrow spin(3-4 degree offset) slow air flow through the inside of the ring and the air that passes over the outside of the ring moves faster. This creates a degree of lift in the same way a plane wing does - yes Im a total geek, bow geek that is, I love this stuff!

[Kirby]

Beacuse the vanes are encircled, this outside ring or structure actually functions as a wing as it pass through the air. The offset of the inner vanes which induce your arrow spin(3-4 degree offset) slow air flow through the inside of the ring and the air that passes over the outside of the ring moves faster. This creates a degree of lift in the same way a plane wing does - yes Im a total geek, bow geek that is, I love this stuff!

Ya.... uh if its shaped like a wing, the lower half would also be causing "lift" in a downward motion. I really don't see that working. Basic physics says that it would be neutral.

Kirby

[Bowzone_Mikey]

Beacuse the vanes are encircled, this outside ring or structure actually functions as a wing as it pass through the air. The offset of the inner vanes which induce your arrow spin(3-4 degree offset) slow air flow through the inside of the ring and the air that passes over the outside of the ring moves faster. This creates a degree of lift in the same way a plane wing does - yes Im a total geek, bow geek that is, I love this stuff!

sorry pal ..your physics dont add up its shaped like wing .. but is in 360 degrees... thus causing lift in all directions ...therefore being nuetral ...I dont have a unit in my hand ..but if I am not mistaken but the winged(curved) egde in on the inside of the circle ..so if anything it tries to induce more spin by causing a low pressure higher speed air travel inside the "airfoil" ..kinda like how a turbine works ..... If I am mistaken ...and the curved surface is on the outside ... then it will do nothing but slow down your arrow ....

oh and by the way ... having weight on the back of ones arrow does not nessiarily help ones FOC .. or front of center balance ... Ideally sould be about 11-15% Front of center .... for ease of illustration for our audiance and calaculation you arrow is 100 Cms long ...center would be 50 cm mark ... 13% FOC on that arrow would be 37Cms from the front or 13 cm from center or 63 Cms from the back ...FOC balance point is 13% of the total arrow lenth in front of the center point ...
Having a good FOC will help one create and maintain momentum and solid hit ... if the balance point is far back when your arrow hits somthing solid it will flex like a wet noodle and have no penitration

[Slugman]

Perhaps I didn't explain it too well and I understand what you guys are saying, I thought that too at first but the design does create a DEGREE of lift. When it comes to FOC I couldn't agree with you more it is extremely important for good arrow flight, all I was saying was the increased weight off the back of the arrow does effect the arrows center and thus the FOC of the arrow. I run my arrows at around 13.8% but research I've read seems to point to HIGH foc of 18% or more! Proof is in the puddin tho and for me these things really work!

[Kirby]

I thought that too at first but the design does create a DEGREE of lift.

HOW??

It makes no sense. If it causes lift in one way its gonna cause and equal about of "lift" on the opposite side. its not like a plane where you have a fixed wing surface... FOBS are spinning, as it spins every single point along the ring is going to cause the same action, all of these will cancel each other out, if you don't your gonna get bad arrow flight.

Proof is in the puddin tho and for me these things really work!

Glad they work for you, of the dozen or so guys i know who have tried them your the first to be happy, like you said proof is in the pudding. I remember in the mid 90's when guys were shooting drop away rests and everybody laughed at them... time tells the truth.

Kirby

[Bow Walker]

Perhaps I didn't explain it too well and I understand what you guys are saying, I thought that too at first but the design does create a DEGREE of lift. When it comes to FOC I couldn't agree with you more it is extremely important for good arrow flight, all I was saying was the increased weight off the back of the arrow does effect the arrows center and thus the FOC of the arrow. I run my arrows at around 13.8% but research I've read seems to point to HIGH foc of 18% or more! Proof is in the puddin tho and for me these things really work!

Actually the research that I have studied points to a lower FOC (12% or less) for Aluminiums and a higher FOC for Carbon shafts (13% or higher - to a max of 18%).

Then again, it really depends on what your particular setup "likes"...sort of like a rifle liking one particular "brand" of bullet and/or load than another.

But. like yourself - I'm a gear junky/nerd. I love learning about the equipment and what makes it function better/more efficiently.

[Slugman]

Actually the research that I have studied points to a lower FOC (12% or less) for Aluminiums and a higher FOC for Carbon shafts (13% or higher - to a max of 18%).

Then again, it really depends on what your particular setup "likes"...sort of like a rifle liking one particular "brand" of bullet and/or load than another.

But. like yourself - I'm a gear junky/nerd. I love learning about the equipment and what makes it function better/more efficiently.

Yes there are sure alot of variables that come into play thats for sure - I think the study I read about FOC on-line somewhere the guys name was Ashby? I think any guy that shoots bow is a natural born tweaker looking for that perfect arrow and perfect set-up! When it comes to the FOB and the lift it creates, it doesn't need to be wing shaped to create lift just different rates of air flow. On the website it may of been refereing to a different principle at play maybe vacuum? If you truly are curious and not just a naysayer if you punch in 'starrflight' you'll get the proper explanation behind the design.

[Slugman]

sorry pal ..your physics dont add up its shaped like wing

.. but is in 360 degrees... thus causing lift in all directions ...therefore being nuetral ...I dont have a unit in my hand ..but if I am not mistaken but the winged(curved) egde in on the inside of the circle ..so if anything it tries to induce more spin by causing a low pressure higher speed air travel inside the "airfoil" ..kinda like how a turbine works ..... If I am mistaken ...and the curved surface is on the outside ... then it will do nothing but slow down your arrow ....

oh and by the way ... having weight on the back of ones arrow does not nessiarily help ones FOC .. or front of center balance ... Ideally sould be about 11-15% Front of center .... for ease of illustration for our audiance and calaculation you arrow is 100 Cms long ...center would be 50 cm mark ... 13% FOC on that arrow would be 37Cms from the front or 13 cm from center or 63 Cms from the back ...FOC balance point is 13% of the total arrow lenth in front of the center point ...
Having a good FOC will help one create and maintain momentum and solid hit ... if the balance point is far back when your arrow hits somthing solid it will flex like a wet noodle and have no penitration

Dude perhaps you should have been hanging with the guys in lab coats when they were testing this in a wind tunnel to offer your expert opinion - I think the guy who designed these made sure he could back up the science behind how it actually works! Oh and thanks for breaking down FOC for the rest of us dummies!