We’ve got a project going on where we want to string fishing line between two poles. We plan on drilling a hole through the poles to thread the line through so it won’t slip down. What’s the best method to then secure the line? Wrap it around the pole several times and then some sort of knot?
Not sure what your pipes are made of or how long they are.
For a long fishing pole, I’d buy a steel top eye rather than drill the top thin (weak) point. I would also tie the line to the base of the pole and wrap it several times till I reach the top. This is so that if the fish breaks the pole, the line doesn’t go with it.
How thick is the trawl line and what is it made of? Is there reason to think it needs an extra secure knot or that some ordinary hitch is not suitable?
I don’t think the OP is asking a question regarding fishing poles or fishing.
I’m assuming tension is important along with security. You can follow the instructions in the video below and pretend the caribiner in the video is the hole in one of your poles. Will work the same for fishing line as rope.
Just keep in mind, there is fishing line with a strength of 10 or 20 lbs, and there is also thin cord with a strength of hundreds or thousands of lbs, to say nothing of rope… Don’t mix up the applications 
If you ARE trot line fishing, be sure to check the local regulations, as you are not allowed to do it everywhere.
Thanks everyone! We are not fishing - we are stringing fishing line between copper pipes to build a trellis for the garden.
Not much tension needed, so any old knot will do. You can skip through the following videos and see if it looks like any may be helpful.
https://www.youtube.com/watch?v=gH3-5VXWpZQ
What I would worry about would be rough or sharp edges that may cut through your line, which as we said may not be very strong to begin with. You will have to carefully file and smooth the hole and/or otherwise protect the line from chafing. Actually hitching the line to a post so that it does not come loose is a trivial matter, as x-ray vision says; for instance you could take a round turn and finish off with a buntline hitch, or finish off an anchor bend with a strangle knot, or whatever.
Er, I mean, after the round turn(s), finish with a clove hitch or anchor bend or whatever around the standing part in such a way that it will not spontaneously loosen.
My experience as a fisherman is nylon weakens fairly quickly in the environment, both water and uv weaken it, my suggestion would be use rope or wire.
Finish off with a dab of thin c-a glue. It doesn’t actually bond to the nylon of the monofilament directly, but will penetrate all the spaces of the knots and bind it all. Works even better of you use braided fishing line rather than monofilament.
Or just melt the filament. That’s what I do to leather sewing braid.
If you are going to buy new line, rather than just using what you already have, don’t use monofilament. Your best options would be:
Fluorocarbon if invisibility is important. Normally used for leaders, especially around jetties, oyster reefs, and other rough structure, it it much more resistant to nicks and abrasions than monofilament. Buy it in the heaviest test weight you can find - like 80 lb. or so.
Braided line will be more long-lasting, and even more resistant to abrasions. It’s not transparent, low-visibility green works well in water, and I suppose in a garden setting would be almost invisible. It’s also thinner - braid will be smaller in diameter than the same weight mono or fluorocarbon.
Stainless steel leader will probably be the longest-lasting, and even the thinnest stuff on the shelf will be rated at 100 lbs. or so.
As for the knots - just google-up appropriate knots for whichever type of line you choose. A great knot for mono will not necessarily work with braid, for example.
Another idea: if the hole is near the top of the pole, tie a kind of Palomar knot or even a pile hitch by passing a doubled end through the hole, coming around the outside to form an overhand knot and slip the bight over the top. No way that’s going anywhere, no glue or cement or melting required…
If not nylon, braided UHMWPE or steel should be fine even out in the sun and rain for years, no?
Bayaker touched on this, but what kind of line is it? Monofilament is terrible at holding knots.
It won’t be invisible, but amateur radio guys like me use black dacron line to hang and support antennas. The black dacron is UV resistant and lasts for years outdoors.
I’ve got a length of 1/4" holding an antenna thats been up for 16 years so far with no issues.
Why not use copper wire. Fishing line is not a good choice, IMHO.
Goodluck.
Drilling a hole through the copper may not be your best solution. I would get some Landscaping Spikes. Use what ever wire, rope or monofilament and tie it around the spike and drop it into the copper. I would also get some big washers to prevent the spike from falling down the pipe.
Tie your line to the top of the spike and drop it in using a big washer to keep it from falling through.
Also, I would consider using a truckers hitch knot if using any type of rope paracord. It can be tightened and adjusted easily. They are really easy. I use 'em all the time.
They give you the advantage of a pully in the rope itself.
Lot’s of instruction online.
Thank you everyone, you’ve given us a lot to consider. We originally went with fishing line due to the cost (not necessarily the aesthetic) and are reconsidering - wire may be what we end up with because I have no desire to restring this trellis every year (or more frequently!)
Save yourself the trouble of drilling by using constrictor knots: Properly tied (easy to do), they emphatically will not slip.
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