Home Tournaments Calendar Weather Merchandise Sponsors

Go Back   Spearboard.com - The World's Largest Spearfishing Diving Boating Social Media Forum > Spearfishing Gear > Non-Gun DIY Projects and Customizations

Non-Gun DIY Projects and Customizations This section is for your DIY spearfishing projects and customization other then spearguns.

Reply
 
Thread Tools Rate Thread Display Modes
Old 10-14-2016, 12:11 PM   #1
CyborgDroid
Registered User
 
Join Date: Aug 2016
Posts: 13
2L coke bottle float

I have been using a 2L coke bottle as a float for my pole spear and gun to avoid dropping it when in deeper water than I can dive. It works great so far. Most commercial floats are 15L+. If I was going to use a few coke bottles to float small-medium fish instead of the gun reel, how many liters would I need? 2-4 coke bottles enough (4-8L)?

Thanks.

Sent from my VIVO 5 using Tapatalk
CyborgDroid is offline   Reply With Quote
Old 11-04-2016, 01:38 PM   #2
kingfisherflesh
Happy Huntin'
 
kingfisherflesh's Avatar
 
Join Date: Apr 2008
Location: Wherever the fish take me
Posts: 658
Re: 2L coke bottle float

Could you describe your float more?

Details of the construction will help others to know what it can handle.

Generally coke bottles are pretty weak and thin walled - and in addition you may have weakened it further depending on how you attach your spear.

Lastly and most importantly if used to fight a fish, it will crush very easily and at a shallow depth.

Commercial floats are filled with pressurized air or foam to prevent them from crushing.
__________________
Dude, put the controllers down and go dive!!!----David Deman

WISCONSIN SPEARGUN HUNTERS
kingfisherflesh is offline   Reply With Quote
Old 11-04-2016, 03:02 PM   #3
CyborgDroid
Registered User
 
Join Date: Aug 2016
Posts: 13
Re: 2L coke bottle float

Coke bottles are quite strong. They explode at 10bar of air, most floats go up to 2-3bar recommended pressure. So if you inflate the coke bottle to 4-6 bar it should be quite stable and will not crush until 30-50 meters deep. Line is dyneema or spectra core, same as reel line. Figure of 8 to create a larkshead that attaches to the coke bottle neck, and add two constructor knots just to be sure it doesn't come off. The figure 8 knot is just the right length so that the larkshead is "locked" in place around the neck by acting as a stopper to avoid it loosening at all since plastic is slippery and the neck ring is thin. I'll upload a picture tonight. The downfall is the limited buoyancy offered by a 2L float. Great for making sure you dont drop your speargun or polespear in the deep, but probably not for fighting fish unless you daisy chain them or something. Its a free float you can pick up anywhere when travelling, add your caps with the inflate valve and good to go.

Sent from my VIVO 5 using Tapatalk
CyborgDroid is offline   Reply With Quote
Old 11-04-2016, 03:14 PM   #4
CyborgDroid
Registered User
 
Join Date: Aug 2016
Posts: 13
Re: 2L coke bottle float

This video is about making a compressed air tank out of a 2L coke bottle.

https://youtu.be/r3D5FAPwqj8

They also made an array of these here:

https://youtu.be/mx7_03ryFVQ

And here is the pressure test:

https://youtu.be/SDTvjJZlnR8

Sent from my VIVO 5 using Tapatalk
CyborgDroid is offline   Reply With Quote
Old 11-04-2016, 03:24 PM   #5
kingfisherflesh
Happy Huntin'
 
kingfisherflesh's Avatar
 
Join Date: Apr 2008
Location: Wherever the fish take me
Posts: 658
Re: 2L coke bottle float

Very interesting.

You have a lot of thought invested into this.

I still think I would have used a thicker plastic, but it obviously can stand up to pressure.

Did know that you were pressurizing them.

I think what you need to do now is test how much lift these have in water - and then compare them to the numbers we have on various floats and design something comparable.

I think that a RA foam filled 12L is about 23# of lift.
__________________
Dude, put the controllers down and go dive!!!----David Deman

WISCONSIN SPEARGUN HUNTERS
kingfisherflesh is offline   Reply With Quote
Old 11-06-2016, 04:01 PM   #6
Ron S
Registered User
 
Ron S's Avatar
 
Join Date: Nov 2005
Location: Truckee, CA
Posts: 4,793
Re: 2L coke bottle float

This is pretty cool! If the coke bottle is strong enough, but you want more floatation, what about a 1 gallon disposable water jug? I don't mean the ones that look like milk jugs. I mean the clear ones with beefier screw on lids. They're pretty robust.
Ron.
Ron S is offline   Reply With Quote
Old 11-06-2016, 04:35 PM   #7
saltysunburns
Registered User
 
Join Date: Aug 2016
Location: Miami, FL
Posts: 22
Re: 2L coke bottle float

Ritz Cola 3L bottles...fill it with expanding foam?
saltysunburns is offline   Reply With Quote
Old 11-12-2016, 11:01 AM   #8
Alec
Shoot em' up
 
Alec's Avatar
 
Join Date: Sep 2010
Location: Palm Beach
Age: 22
Posts: 1,995
Re: 2L coke bottle float

Hope you don't plan on shooting anything bigger than rainbow runner or spadefish
__________________

Spearfishing & Freediving Supplies
501 Harbor Blvd
Destin, FL 32541
Shop # 850-837-3315
http://benthicoceansports.com/
Alec is offline   Reply With Quote
Old 11-13-2016, 04:37 AM   #9
Diving Gecko
Shooter & Shooter
 
Join Date: Nov 2014
Posts: 584
Re: 2L coke bottle float

Quote:
Originally Posted by CyborgDroid View Post
Coke bottles are quite strong. They explode at 10bar of air, most floats go up to 2-3bar recommended pressure. So if you inflate the coke bottle to 4-6 bar it should be quite stable and will not crush until 30-50 meters deep. Line is dyneema or spectra core, same as reel line. Figure of 8 to create a larkshead that attaches to the coke bottle neck, and add two constructor knots just to be sure it doesn't come off. The figure 8 knot is just the right length so that the larkshead is "locked" in place around the neck by acting as a stopper to avoid it loosening at all since plastic is slippery and the neck ring is thin. I'll upload a picture tonight. The downfall is the limited buoyancy offered by a 2L float. Great for making sure you dont drop your speargun or polespear in the deep, but probably not for fighting fish unless you daisy chain them or something. Its a free float you can pick up anywhere when travelling, add your caps with the inflate valve and good to go.

Sent from my VIVO 5 using Tapatalk
I love this idea, ghetto floats! I might do this in the Philippines.

In terms of using bigger water bottles, there might be an issue - big bottles tend to have bigger caps. Bigger caps have more surface area which means the compressed air will exert way more force on a bigger cap than a smaller one. So, while the smaller caps hold up to the pressure, the bigger one might not. Worth testing, though.
Diving Gecko is offline   Reply With Quote
Old 11-13-2016, 06:50 AM   #10
SEATUX
Registered User
 
SEATUX's Avatar
 
Join Date: Apr 2005
Location: Port Charlotte Fl
Age: 70
Posts: 1,861
Re: 2L coke bottle float

The 1.75 L Canadian Club is possibly even stronger..but like Diving Gecko said, the cap may be the limiting factor.
SEATUX is offline   Reply With Quote
Old 11-13-2016, 11:19 AM   #11
Freedvrjim
straight shooter
 
Freedvrjim's Avatar
 
Join Date: Jul 2008
Location: Wrong Island, NY
Posts: 1,046
Re: 2L coke bottle float

Quote:
Originally Posted by Diving Gecko View Post
I love this idea, ghetto floats! I might do this in the Philippines.

In terms of using bigger water bottles, there might be an issue - big bottles tend to have bigger caps. Bigger caps have more surface area which means the compressed air will exert way more force on a bigger cap than a smaller one. So, while the smaller caps hold up to the pressure, the bigger one might not. Worth testing, though.
duct tape the cap?
__________________
Do like you want, like what you do.
Tristateskindivers.com
Freedvrjim is offline   Reply With Quote
Old 11-15-2016, 05:32 AM   #12
Diving Gecko
Shooter & Shooter
 
Join Date: Nov 2014
Posts: 584
Re: 2L coke bottle float

I was thinking more like adding a layer of carbon fiber, haha. But that's overkill. You could prolly wrap some thin dyneema around it to do the job - if it's the threaded part which gives. But the more I think about it, the more the whole idea might be overkill. I mean if you need to blow your float up to avoid it collapsing at +30m then it's prolly a fish that doesn't care about a 2l float...;-). I still like the idea and for reef fish and with persons the slightly larger bottle, I'll still keep it in mind.


Sent from my iPhone using Tapatalk
Diving Gecko is offline   Reply With Quote
Old 11-15-2016, 02:48 PM   #13
9x19MdM
Registered User
 
Join Date: Aug 2014
Location: Western Arkansas
Posts: 306
Re: 2L coke bottle float

This 1 gal/3.75L style of bottle/jug is thicker than milk jugs and has a great handle to tie on to.

9x19MdM is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 12:50 AM.


The World's Largest Spearfishing Diving Social Media Forum Powered by vBulletin® Version 3.8.1
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright ©2002 - 2014 Spearboard.com