I'm intending to change my single to double glazing on teak frames.I'm a carpenter and intend to do it myself. Problem is removing rock hard putty without damaging the frames.Has anyone seen the professionals do this process.Also a standard router won't rebate into the corners.What kind of tool do they use for this. Any suggestions would b appreciated.
Unfortunately, it is a slow painful process removing the old putty, and you will have to deepen the rebate in the corners with a chisel.
Where the sashes open get new sashes made as they will now come with rubber draught seals or groove the sash yourself and fit some rubber draught seals.