How long are your painter ropes? What kind of rope works best, nylon or floating polypropolene, others?
For moving water: floating line, no longer than the boat, no knots in the end. 3/8" line is easier to grab than smaller stuff.
What Angstrom said
Longer (25+) painters desireable for lining boats through rapids (not uncommon on longer river trips), but boat-length is usual guideline otherwise.
I think the rope that floats is poly, or has a poly core. Floating is the key criteria. The fatter the better if you are going to be grabbing the painter in swim situations.
my painters are for tieing up
I’ve towed a boat or two, badly with them, but mostly I use my painter to tie the boat to a tree or rock while i am piddling or having lunch so it doesn’t float away.
So I use 1/2" yellow poly (because that is what I had on hand) but never thinner. Carabiners at both ends. One at the bow, the other clipped to the seat inside the kayak. Poly only so it will float and is eaier to catch when the boat drifts away.
Length, well, long enough to reach that tree and i hate to cut rope so pretty much whatever length i have on hand that will work.
Spectra floats too, but is probably
overkill. I use short, 10’ painters on my whitewater canoes. Polypropelene is nice in some weaves because it is lighter than water, and has little affinity for water, so it doesn’t get sodden.
In whitewater situations, the ends of the painters should be tied or taped, but never knotted. Those knots have a way of getting caught in rock crevices.