Glazing question - old sash window

[bethrob99]

I'm attempting to restore a Victorian sash window. I have successfully removed some of the panes of glass but have just discovered that the horizontal edge where the windows meet up has a channel the glass slots into instead of just lying on the surface of a rebate. It appears the glazing process would have involve running a bead of putty along the groove and rebates, pushing pane of glass into groove and dropping it onto rebates before pinning and puttying the edges. How the blazes can I remove the glass? Can I re-soften the putty? Would it be possible to grind the putty out with a little Dremel tool? Any idea how deep this channel is?

Any advice much appreciated. One of the panes was already broken, but I really want to keep the others and don't want to risk a heat gun because I sure as hell will crack everything. (I scrounged a neighbour's sash for spares and they also had the same pane cracked!)

 

[pinenot]

I take it your trying to retain the glass whole?
Putty is made with linseed oil and can be softened with it, but it wont happen quickly. Try soaking the visible putty overnight, fit a suction cup to the glass and apply a sustained pull up/down action to see if there's any movement, if there is you can work it out of the slot eventually. If your not trying to save the glass, smash it and get a thin chisel or similar into the slot and remove all...pinenot

 

[bethrob99]

If the putty went in over 100 years ago I expect I'll be applying linseed oil for several weeks. Does it make a difference if it is plain or boiled?

 

[pinenot]

actually normal engine oil softens putty as well, so with that I wonder if a release oil would work, could be worth a try, Raw linseed oil if you have it...pinenot

 

[gregers]

probably 4mm glass,smash it coz id be surprised if you will get it out whole,as the rebate will be about 10mm deep.

or you could try using a glass cutter and salvage as much glass as you can then recut for any smaller panes that are needed?