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geodaro
12-11-2003, 11:05 AM
Please be gentle, I'm new to spearfishing (but not to diving) and and somewhat mechanically challenged!

My question is this - what is the best (or even easiest) method used to mark a spot for diving once you have seen good bottom on the bottom machine?

Here is my current setup: 1/2-gallon milk jug (bright yellow) with about 75 feet of yellow twine rolled onto it. I tie the line to a 3 pound lead diving weight and just throw it overboard when I see good bottom on the machine. The problem with this method is that the weight often gets stuck and is difficult to retrieve and the line is so thin that it cuts into hands, arms, feet, etc., when trying to retrieve. There must be a better way. Any suggestions from the more experienced would be greatly appreciated.

mhuskey
12-11-2003, 04:44 PM
My suggestion would be to purchase a sur-mark, from one of the local tackle shops. They are a marker with a self contained spool for the line storage, that you wind back in with a handle. They are designed so that once the weight hits the bottom it stops the line from going out any further. That way one can use it in 30ft or 150ft with out any problems of the mark drifting around . I use a 5lb sash weight on mine, sometimes it will hang but the best option is to go down the line and move the lead into the sand. If you take a cordless drill and put a socket on it that matches the shaft size you can bring up the weight without a lot of effort. Hope this helps.

Matt

FredT
12-11-2003, 05:33 PM
Rectangular laundry detergent bottles of nearly a gallon size.
Wrap on a known length of braided mason's twine big enough to be comfortable to work with. Fill the bottle with Great Stuff foam and reinstall the cap.

For the bottom weight use cylindrical weights cast in toilet paper tubes. Cap the bottom of the tube with Al foil, then bury the roll axis vertical in a dry sand bed. Cast to fill the tube embedding a wire loop in the molten metal for a tie off spot. Coat hanger wire makes a decent 1 year loop, SST welding wire is good for a decade but actually costs something. Weight will be about 4 pounds after you peel the paper off it. Salvaged dive and fishing weights from wrecks and ledges are good lead sources over time so the weights after the first batch will be free for the melting fuel & labor. The first batch of lead may come from wheel weights "donated" by your local tire store. Be aware it generally takes about 5 pounds of used wheel weights to get 4 pounds of clean lead.

Write the maximum water depth (line length x .8 or .9) on the bottom of the bottle. Slip the weight through the jug handle to store, pop it back out to use. Make several with water depth ratings matching what you want to dive, plus a couple steps deeper. When you get to the site, simply grab the appropriate jug for the sounder depth reading and pop the weight back through the handle. Run from down current up to remark the site, and toss the buoy/weight assembly overboard as the sounder marks the upcurrent structure edge.

The longer cylinder won't snag on the bottom like a block weight, cost is minimal, and if you tie the line on with a "soft section" of lighter line at the bottom if the weight does snag you can snap it off easily and replace it with one of the spares on board.

Reel Cracker
12-11-2003, 09:13 PM
FredT jug will work but the best weight to use is the old window satch weights. If you use those dive weights for the jug line they have a tendancy to plane off on the drop and won't go straight down.

FredT
12-11-2003, 11:30 PM
Originally posted by Reel Cracker
FredT jug will work but the best weight to use is the old window satch weights. If you use those dive weights for the jug line they have a tendancy to plane off on the drop and won't go straight down.

Please note the weight I suggested is smaller than a sash weight, weighs about 3.8 pounds depending on alloy and mold leakage, and won't plane. They won't rust when stored on the boat if SST wire or cable is used for the loop. It also won't pull the jug under if the line snags on deployment.

FT

geodaro
12-12-2003, 08:58 AM
Thanks a ton for the input. It looks like I will have some fun this weekend building the "perfect" marker bouy! I just knew there had to be a better way to do it! I love this web-site!

mushkee
12-12-2003, 09:30 AM
fredt,
nice autocad skills, im in my autocad class right now as I type...

Doyle
12-12-2003, 11:05 AM
If you are going to make your own out of a jug, try to find jugs that are smaller in the middle than they are at the top and bottom. That way the line tends to stay on better. I used one that had contained Admix (the latex additive that tile layers use).
For line, I found that "crab trap line" works very well.

FredT
12-12-2003, 11:41 AM
Originally posted by mushkee
fredt,
nice autocad skills, im in my autocad class right now as I type...

It's kind of a very intuitive Autocad crippled in 2D, but it's primarily a decent low budget 3D tool similar to SolidWorks. It's been about 6 years since I did any intensive work on an AutoCad system, but I did run one for about 10 years.

I didn't have access to the Pro-E I usually run at the office last night, but I keep a copy of CadKey on the home box for simple concept stuff.

Autocad is a highly configurable general purpose tool, and great for learning the basics of CAD. The primary drawback to it is that by the time you get a configuration set up to do real engineering on it with all the "adder modules" and "libraries" necessary it costs almost as much as a good integrated fully parametric modeling program that is about 10X more useful.

FT

FredT
12-12-2003, 01:01 PM
Originally posted by Doyle
If you are going to make your own out of a jug, try to find jugs that are smaller in the middle than they are at the top and bottom. That way the line tends to stay on better. I used one that had contained Admix (the latex additive that tile layers use).
For line, I found that "crab trap line" works very well.

If you wrap the line tightly around the jug before filling it with foam you'll form a reduced diameter "waist" when you foam it.

FT