This weekend was spent reinstalling panes. I have reinstalled panes in 3 1/2 sashes (6 sashes in project). I will glaze all sashes at the same time.
Before reinstalling the panes I first made sure all the old glazing, paint, and debris was removed from the wood. Be careful not to nick or split the wood. Muntin bars are very delicate. I have already glued several that were split before I started the restoration.
I used a variety of tools to remove the old glazing compound. Most of the time a putty knife with a sharp edge will work. To remove glazing from corners, I use a little bent probe. You can buy a 4 piece assortment at Harbor Freight for around 5 bucks. These are normally used for removing O rings but they work great for digging crud out of corners and small cervices. When that doesn't do the trick I use my Dremel with a barrel sandpaper bit. Be very careful not to gouge the wood. I have found that setting the speed at 1 or 2 at the most is sufficient. Keep the tool moving.
My windows had a variety of "stuff" used as glazing compound. First the traditional glazing compound which either dried and fell out or was rather easy to remove. The second type was paint. Seems that the PO had used paint to fill any cracks in the glazing compound. The third substance is unknown, but I can tell you it was hard.
I start to prepare to reinstall the panes by first making sure all compound, paint, and broken glazing points are removed. I then use a dry paint brush to brush away loose particles. You could also use a shop vac but my cats don't like the noise. I next brush on some boiled linseed oil. Some prefer oil base primer but I don't want to have to worry about primer getting on the interior side which at this time is stained. I think the main thing is to seal the wood so that it doesn't pull all the moisture from your glazing compound which in turn dries it out causing it to crack and lose it usefulness.
Make sure you cover both the vertical and horizontal surfaces. I may or may not apply more than one coat. I usually apply a second coat if it looks like the wood is still dry. In any case, I let it sit and absorb for 30 minutes or so.
I next lay down a small amount of glazing compound for the pane to rest on. First knead the compound in your hand for several minutes. This really helps with the workability of the compound. I also never reuse any compound that falls on the table or floor OR becomes contaminated with dust or small particles of debris. Glazing compound is cheap. You've invested a lot of time into re doing your windows, now is not the time to be cheap.
I carefully lay the panes onto the compound. Do NOT force the panes into place. I place all my panes into the sash before I install any glazing points. This insures that all my muntin bars line up. Muntin bars just float in place and really only gain their strength once the panes are permanently installed. Any compound that oozes out the back can be removed after all the panes are firmly in place and glazing points installed. Only after this is completely done, do you attempt to turn over the sash and remove the excess compound. I use the glazing tool again to remove the compound. Discard this compound if it has come into contact with any dust etc.
I usually let the sash sit for a day or two before I move onto glazing the window. If I am just replacing a single pane I immediately glaze the window.
Also make sure you get all your glazing points and panes installed before your nail (fingernail) appointment comes up. You will need a manicure STAT after working on your windows. Be prepared to answer the question, "What have you been doing?" after Madge gets a look at your hands. Don't forget to tip generously on those days.
Time invested this weekend 8 hours. Total time invested.......30 hours.