What slows down a shaft the most?

Hahaha, nice, billy good luck making the dimples on the shaft, about the golf design, Lance Amstrong in his last Tour the France he had a jersey made that the texture was like a golf ball, it was for the time trial even and it was suppose to be faster because the wind could slide better.

Quote from hau

[quote='Tin Man','http://spearfishing.world/forums/index.php?thread/&postID=22512#post22512'] about things that slow down a spear shaft.

Obviously, there are lots of things that create drag and rob energy from the spear.

I hesitate to write this, but in response to Tin Mans statement, IMO, spear weight is also a very important factor related to spear speed. IMO, a shorter spear weighs less, is faster and stiffer than a spear of the same diameter that is just 1in longer. That s why I personally shoot the shortest spear possible. Though this opens the discussion of spear speed and spear weight as related to kinetic energy. A lighter weight spear will be faster than a heavier spear, but a lighter spear traveling at the SAME speed of a heavier spear will have LESS kinetic energy. If spear speed is the GOAL, then lighter spears is a major factor. I am not saying that thin,short spears are better for real life spearing, I'm saying that shorter, light weight spears are FASTER.

But, if to thicker spear to take more powerful bands, the spear will fly as quickly?

Quote from aquaolga

[quote='hau','http://spearfishing.world/forums/index.php?thread/&postID=22558#post22558']

But, if to thicker spear to take more powerful bands, the spear will fly as quickly?

Here are some approximate muzzel velocity's of shafts shot from my old Mares in fresh water, all at 20 Bar.
(wet barrel)
7mm shaft=34m/sec
8mm shaft=29m/sec
9mm shaft=26m/sec

Cheers, Don Paul

115cm asso tovarich (25 Bar) with 9/32 shaft is probably the fastest shooting shaft i have used. It would reach the end of the mono super fast. Everything else just seems slow after shooting that gun. My Denton shoots pretty fast but not as fast. A railgun feels like slow motion.

Quote from greekdiver

115cm asso tovarich (25 Bar) with 9/32 shaft is probably the fastest shooting shaft i have used. It would reach the end of the mono super fast. Everything else just seems slow after shooting that gun. My Denton shoots pretty fast but not as fast. A railgun feels like slow motion.

Oh the call of the wild is beckoning, I feeling a pull back toward the Dark Side I may have to try using a air gun in the big surf this year. If lose it I can just buy another one.Where I'm going to dive for big White Sea Bass is down a very steep cliff trail. A 115 would sling over my back with my fins.:D Ok... I start a new thread.
Cheers, Don

Quote from greekdiver

115cm asso tovarich (25 Bar) with 9/32 shaft is probably the fastest shooting shaft i have used. It would reach the end of the mono super fast. Everything else just seems slow after shooting that gun. My Denton shoots pretty fast but not as fast. A railgun feels like slow motion.

Oh the call of the wild is beckoning, I'm feeling a pull back toward the Dark Side I may have to try using a air gun in the big surf this year. If lose it I can just buy another one.Where I'm going to dive for big White Sea Bass is down a very steep cliff trail. A 115 would sling over my back with my fins.:D Ok... I'll start a new thread.
Cheers, Don

Quote from LunkerBuster

Don, is it really possibly for there to be laminar flow along an object that is both creating forward disturbance and cavitating? isn't there going to be at least micro turbulence around the shaft?
i see how laminar would be ideal, but i feel like that is only possible on paper, no?

I have often wondered if the turbulence created by releasing the bands would disrupt the fluid dynamics effecting the shaft as well as the shafts own properties as it moved...

Sorry I just saw the post.Yes perfect laminar flow is not very likely with our sliptips, shaft tabs, fins and heavy
mono. long thin shafts are also susceptible to drag gyration. drag gyration is defined when the rear of the shaft
rotates concentrically about it's axis in a circular motion off the flight trajectory line. The faster it go's, the harder it is to go fast. Shite I just realized I came to a Fun forum with cool bikini pictures and now I'm making this place sound like Work.:@:D Here's some shaft porn.:D
Cheers, Don

ooooooh sexy

I don't see the bikini....

Quote from Marco

I don't see the bikini....

Here you go.....:D

HA!

Thought you guy's could used this:
Don

I did some un sanctioned testing in my apt pool on saturday night.

I set out with this in mind...one gun w many variables that could be changed one at a time...

I used my AB biller 54 floridian and a 20lb cat litter container filled with sand.
the test was simply to determine which shooting configurations slowed down the shaft the most and how much..I did this by placing the target 10 and then 20 ft away and seeing if it could penetrate the target with the following factors

1) single vs double(floridian one long one short opposite sides) flopper- both 7.5mm (freeshaft)
2)double flopper vs double flopper with a tip guard(just to see how much a blunt cork could slow the shaft down
3)double flopper shaft w line v without
4)double flopper lineshaft v double flopper lineshaft w reel attached w pigtail snap.

for such an unscientific test, i was surprised that the thing that seems to slow the shaft down the most is the lineshaft(at least in a biller configuration w slide ring.

1) both shaft full penetration on both targets
2) both shafts made it to the target and the one w the cork pierced the cork on the short target and knocked over the second...not slowed down very much
3)free shaft penetrated both targets. line shaft penetrated the 10ft and didn't even reach the 20ft
4) both penetrated the 10 ft and neither reached the 20ft

I know that alomost none of us use a slide ring, and now the reason why is clear.

I wish I could have done this testing w my RA, but it was too cold to get in the 25m lap pool and i fear that the RA freeshaft would shoot the full 30ft pool and that would be a no no for my complex
once I can do a daytime test I'll try in the long pool

the glaring lack of science here is fairly hilarious, but the data is still valid, just not very detailed

Don insired me to do SOME testing with all the awesome stuff he's posting

well Jeff, the shaft i tested without the line still had the slide ring on it and i didnt notice and appriciable difference..this is the "low profile slide" for the Floridian shafts..it is a lot smaller than the traditional wrapped metal ones...I will add that comparison to the next testing i do and use a true freeshaft vs lineshaft w no line attached..good thinking...

..but that's why you are The Tin Man and I am just an engineer who couldn't make it and ended up a lawyer

Don insired me to do SOME testing with all the awesome stuff he's posting Quote: LunkerBuster.

Way Cool .... I just don't want to inspire you to not hurt anyone nether.I've done some real stupid shite over the years.

Safe in water testing will give guy's a new tool in their spearfishing kit. The point of all this is not just the
findings, it's the quest to refine all gear we use and build.:thumbsup2:

All the best, Don

Quote from Tin Man

Thanks for the elaboration. I'll have to look up the low profile slide ring that you referred to, as I don't think I know what that is.

I don't have use silde rings but I think he's comparing the old wound spring (hi drag) to the thinner
stamped sheet, or investment cast type.
Cheers, Don

The thinner the shooting line the higher the shaft speed @ range. If a loop of fat 500 mono is drug as
the shaft leaves the barrel it's putting on the brakes.

Cheers, Don

Jeff, here is a bit more about the rings

http://www.abbiller.com/replacement.html

the bottom of that page shows the Biller slide rings.

the one I am referring to as "low profile" is the SLR-C, the one I call the "old type" is the SPR