When all the front putty is gone extract the nails & lightly hit the frame on the inside both sides top & bottom with a mallet to loosen the glass.
Derek Williams
February 2007
I was a glazier for 55 years,use a hacking knife & hammer or a wood chisle.sometimes you can scrape the putty out useing the chisle side on.If you use a chisle & hammer put the bevell edge to the putty or you will cut into the frame to easily.I hope this helps you.
Derek Williams
February 2007
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