Procedure for installing distance markers on a line

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WJL

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Location
metro Detroit
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I have a question about a good protocol for installing distance markers on a line.

Here's the background: We sometimes dive in a local lake for fun and to practice. The bottom is generally flat, weedless deeper than 25 feet, silty and for most of the year the visibility is in the 10 to 20 foot range - in other words it's a typical northern inland lake. Scattered around the bottom of this lake are various largish items, such as sunken boats, car parts and sections of dock. We have run lines to many of these things, so we can find them again. Some of the lines are fairly long - more than 1000 feet. We decided to install line arrows on some of these lines with distance markings on them to give people an idea where they are and which way is home.

So, this is the method my buddy and I used to mark off the line. We used one of those 100 foot plastic tape measures that crank up to measure the distance. My buddy and I were on our scooters. We started off sticking together as a team. We tied the end of the tape to a point on the line, then reeled out the tape along the line until we reached 100 feet, then installed the line marker, then scootered back to the beginning of the tape measure and untied it, reeled it up, scootered back to the just-installed marker, and repeated the process. This lasted about one iteration, as it was a giant pain in the @$$ - both of us are going back and forth over the same 100 foot section three times to install one marker and be ready to start on the next one.

I already know we are going to hell, but what we ended up doing was this: One person held the end of the tape measure by the line while the other person scootered off along the line reeling out the tape. When the reeler reached 100 feet, the reeler gave two sharp tugs on the tape, to tell the person holding the end that the 100 foot distance had been reached. The person holding the end of the tape then scootered along the line pulling the end of the tape along. The reeler meanwhile installed the line arrow and waited for the person with the end of the tape. When the person with the end of the tape arrived at the new line arrow, we repeated the process.

Using the "go to hell" method we were able to go much faster and accomplished the tedious task of installing many line markers pretty quickly. Of course we were separated by 100 feet at maximum and out of sight from each other for the time it takes to scooter 200 feet or swim 100 feet. We have talked this over a few times because we are uncomfortable doing things this way. The "go to hell" method has the advantage of being efficient, but has the risk of being apart if (when?) something goes wrong. We consoled ourselves with the observation that 100 feet of separation is about the distance we covered in a no-mask, no-air separation drill we did in cave class. But still, there are obvious problems.

The one solution we came up with was to have two two-person teams do the installation. This works, but is so boring that it is hard to get anyone to participate.

So, my question is, is there a better method of marking off and installing the line markers using just two people?
 
So, my question is, is there a better method of marking off and installing the line markers using just two people?

How exact to you have to be?


You could measure how much time it takes to go 100 ft with your scooter and just put a marker down on the line when you scooter for that duration.
 
How about marking the lines before you put them in the water? Wont be exact as the lines will stretch but it would be easy.
 
How exact to you have to be?


You could measure how much time it takes to go 100 ft with your scooter and just put a marker down on the line when you scooter for that duration.

What about pre-marking the line before you put it on the reel (with a knot) every 100 feet.

Then as long as you "start at a knot" every next knot will be approx 100 feet.
That might give you "good enough" accuracy.

then just scooter down the line and install arrows at each knot
 
How exact to you have to be?


You could measure how much time it takes to go 100 ft with your scooter and just put a marker down on the line when you scooter for that duration.
That sort of works, but we found it compounds errors over long distance. For example, before we measured it out, we thought one section of line was about 1500 feet. It turned out to be closer to 1200. We ended up concluding we needed some sort of actual distance measuring device.
 
What about pre-marking the line before you put it on the reel (with a knot) every 100 feet.

Then as long as you "start at a knot" every next knot will be approx 100 feet.
That might give you "good enough" accuracy.

then just scooter down the line and install arrows at each knot

Works great when installing new lines, but old existing lines?
 
Pre-marking the line is what I've done in the past. Rather than knots, I use a Sharpie. Varying the thickness of the marking for various increments. e.g.. 2x thin = 20ft or 1x med + 3x thin = 80ft. You could also combine thickness w/colours as well depending on the colour selected and depth of use.
 
What about pre-marking the line before you put it on the reel (with a knot) every 100 feet.

Then as long as you "start at a knot" every next knot will be approx 100 feet.
That might give you "good enough" accuracy.

then just scooter down the line and install arrows at each knot
We did that for for the initial line from the object we designated as the point of origin. Later lines ran from different objects in different directions. For example, there is a sunken speed boat 175 feet from the origin. So when we ran a line from this speedboat to some other place, there are knots every 100 feet, but that is not the same as the 100 foot increments back to the point of origin. The distances we are marking off are in 100 foot units from the origin.
 
As far as the measuring methods... what about using an alligator clip on the end of the tape... a sharp tug on the tape should release it... but then again the line might suffer from the tugging....

just a suggestion
 
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