I am trying to fix a curtain rail in a dormer window. The problem is that the internal wall is brick with lime mortar. Many of the bricks are very poor quality and crumble when drilled. Occasionally I do find a good brick but most of the time they crumble. Is there a way to effectively fill the holes to give them strength. I am planning to use a wooden batten on the wall and fix the curtain rail to that.
If you're using a hammer drill, try using a regular drill (or turn hammer mode off) and the masonry bit. Spin fast, push slow. Oversize the holes and use plastic plug anchors to provide some cushion.
Once you do get a few solid connections, use some construction adhesive or silicone on your batten for additional support.