I apologize for leaving you without a window since my last post.
We now come to the interesting part of the process. You need to get the sash cord over the pulley at the top of the jamb, and to get it to fall down into the pocket so you can grab it and tie it to your sash weight. Unbundle a bunch of sash cord. Locate the pulley, it is near the top of the jamb. You will push the end of the sash cord over the pulley. You must continue to push sash cord through that hole, until you’ve pushed enough to fall down into the pocket to grab through the space where the pocket cover was. You will check the pocket, look for the sash cord, and then push a bunch more sash cord, hoping it will fall down. You know that it is just balling up beyond the pulley, but perhaps if you keep pushing it will start falling, but it doesn’t. If it should happen to fall into the pocket, and you can grab it, you might as well know it was a fluke and it will never happen again. If it should happen to fall and you can grab it, tie it to the weight. If it doesn’t, it’s time to take a length of wire, bend an open hook at the end of the wire, and insert the wire upward in the pocket and go “fishing” for the sash cord. You might get lucky, and catch it. If not, keep fishing. Try not to swear at the sash cord, it is very sensitive. Keep fishing. Do not, under any circumstances, try to push the wire over the pulley to lead the sash cord down into the pocket. The wire will get stuck and never come out. So I’ve heard. We would never try such a thing.
Keep fishing, keep pushing cord, and eventually you will get the sash cord to come down behind the jamb and you can tie the end to the sash weight. Make a good knot, double check that it will hold. Give the cord a little shake, if the sash weight falls on your foot you didn’t tie a good enough knot.
You’ve got the weight tied, and now you need to put it back into the pocket. Just set it there, and pull the sash cord over the pulley until it is taut. Then pull it a little further, so the weight is hanging about an inch above the bottom of the pocket. As you hold this, pinch the cord right as it comes out of the pulley, this is where you want the knot. Pull the cord toward you, and keep your fingers pinching the place you want the knot. Cut the sash cord about five or six inches below the place you are pinching the cord. Do not let go of the sash cord. No, that’s not quite what I mean to say. What I mean to say is DO NOT LET GO OF THE SASH CORD! Yes, that’s it. You will tie a knot, like the one you pulled out of the window, in the sash cord making sure it tightens right where you are pinching. Generally, it is just a loop that you put the tail through twice instead of once. That will make the knot big enough that it doesn’t go through the pulley.
Once you have this knot tied (you have not let go of the sash cord, so you haven’t had to go “fishing” a second time) let the weight drop slowly. The knot should stop at the pulley, and the weight should still be dangling. If this is true, you’ve done it correctly.
Repeat this process on the other side. Cake, huh?
Now, with the two knots at the pulleys, and the weights pulling against the knots, you want to replace the covers of the sash pockets. They need to be pushed in, and slid upward. The notches at the top will slide around the nails in the jamb. You may have to use some gentle persuasion (like a hammer against a small block) to get the pocket cover to go completely into place.
Once the pocket cover is in place, replace the screws that you haven’t lost. Do the same on the other side. Now you’ve got smooth jambs against which a window can slide.
Go get the window. Put it back between the jambs, making sure the outside faces out and the inside faces in. Take one of the knots from the pulley, pull it down, and locate the hole in the side of the sash. Stick the tail in the hole first, finishing with the knot, that will hold the tail in. Otherwise the tail will lead the knot out of the hole. Do the same on the other side. Amazingly, you no longer have to hold onto the window, counter weights do keep it in place. Check to make sure the window slides up and down easily.
Replace the stops, making sure to put them on the correct sides with the flat edge against the window and the bevel at the top under the top trim piece. Pound the finish nails into the same holes they came out of and voila, you have a functioning window!