Getting Knotty (Tieing knots in cave line)

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b1gcountry

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Alright, I am in the process of surveying a large cavern area near St Louis, and for the survey we had to tie knots in over 1500' of cave line to provide measurement information for the survey process...we lay the line between intersections, and then take the width of the cavern at every knot--ten feet.

Other divers like to do this with their primary reels, or spools, so here is what I did to help speed up tying over 150 knots in a whole crapload of cave line:

Tools Needed:
Line (Duh!)
Cardboard Box with something heavy in it
Knife/Box cutter
Cheap Floor Lamp
Tape Measure
Cordless Drill
Long Bolt
Fender Washer

Okay, now that I've peaked everyone's interset, here's how it works. First find some open space on the floor--preferably carpeted, as it feels better on the bottomside. Take your line and tie the first knot in it at the end. Measure 10' (or however often you want knots), and tie another knot in the line.

Now, move the cardboard box next to the floor lamp about half the distance away as you want the knots spaced. Make a 1" vertical cut in the top edge of the box, and put the end of the line into this cut. wrap the long end around the floor lamp, and bring it back to the box. Position the box so that both knots are even with the cut you made. Should look like this:

BOX Line Floor Lamp
___
| |__________
| |__________O)
| |
----

Now simply pull the line through the cut in the box until the second know pops through, pinch the line where it touches the box edge, and tie a knot by passing the spool around and through the line. Repeat until done.

When you have all the knots tied, you can rewind the spool/whatever by hand, or do what I did, and pass along bolt with a fender washer near the head through the spool, and chuck the end of the bolt into the drill. You now have the spool sandwiched between the washer, and the drill chuck. Pull the trigger and watch that line wind itself! Woohoo! Go Baby Go! Only word of advice is not to have as much fun as I did with the drill. Also make sure the line doesn't slide off the spool, or you will have to re-do it.

Cheers!
Tom
 
For these kinds of projects, I find that one of those folding lawn chairs works wonders- they keep you off the floor, but not too high that you can't reach into a cooler or toolbox. :wink:

When I respool spools and reels, I like a little tension on the line, so I daisy chain a few double enders together and hang then up from a hanger or some other convenient point. I then run the line though the gates to create some drag. Of course, it might not run so smoothly with knots. :D

Which cavern are you surveying? 1500' sounds too big to be Roubidoux. Maybe Mine La Motte?
 
Yeah, we're going down to the offsets on Sunday. Part of our little effort to get it cleaned up and more be useful to divers. We are doing the open air cavern sections to the left of the main dock on Sunday. Hopefully to expand to the other sections later on. I've found a couple side tunnels that would be pretty easy to accidently wander down (I went in about 10' before realizing the roof over my head), so we'd like to mark the locations of these. There are no warning signs in this part of the mine.

Tom
 
https://www.shearwater.com/products/peregrine/

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