5
5. Here is a close-up of the nibbler cutting head.
wide so that I don’t need to do any cleanup. Any minor irreg-
ularities in the opening will be covered by the outside trim
around the windows. Note that this approach works only when
you are using windows with trim. Windows in masonry build-
ings normally don’t have trim. It also won’t work for small win-
dows if the nibbler head is larger than the opening needed for
the window casting.
Once you’ve finished with the nibbler, check to see if the cast-
ing will fit in the resulting hole. If it doesn’t quite fit, fine-tune
the hole with the hobby knife, carefully carving or scraping as
needed. To see where material needs to be removed, insert the
casting as far as it will go and look from the inside of the wall to
see where it is binding.
