Adding a Halyard with mast up

[Brion Toss]

Hello,
We used to use a length of bicycle chain on a long messenger, but found it too easy to get a foul in it. So now we use a series of peanut-size lead fishing weights, the kind that clamp onto a string. Try about 10 of these, spaced an inch or less apart. Wrap tape between the first few, so they form a slightly stiff section, easier to push over the sheave.
Lean the boat over to the side the exit is on first. Tighten all other internal halyards. Fish the messenger out with a bent piece of TIG rod or the like.
Fair leads,
Brion Toss

[tpg]

I may attempt another method, unless Brion or someone else, talks me out of it.
A know-it-all friend of mine sez to send an electricians "snake" up the mast from the
halyard's exit box at the base of the mast. He asserts that it will be easier to see and grab the snake at the sheave - with me at the top of the mast. Then pull the snake's end out, attach the new halyard, pull it back down. Whadda' you think?

[Brion Toss]

Hi again,
There are many paths to the mountain top ó or the masthead ó but this is a bad one; that snake might be able to support its own weight all the way up there, but it will almost certainly wind around other halyards en route. And when/if it does get to the top, it will be far from easy to "grab it". Let gravity do the work for you.
Fair leads,
Brion Toss