hank wrote:
I have have a house full of double hung windows. ( actually only the
lower half raises and the upper half stays fixed) The spring has a
plastic cover on the upper half which has become brittle and needs to
be replaced. Lockwood the manufacture originally from Canada has gone
out of business
as far as I can tell. Is that plastic sleeve at all a standard
replacement part.for other window manufacture If so where would I
find
them.

They might not be the same but check with one of your local suppliers
to see if you can retrofit aluminum spring balances. They are about
the same thing, but are in an aluminum tube. I know I found some
for my old aluminum windows at Jones Aluminum here in Tulsa. I
know you don't have Jones where you are. They sell all kinds of
aluminum products such as carports and awnings.

Who knows a place like that might have the original plastic ones.
Take one out and take it with you when you find the place so you
can be sure you get the right one.

Good luck
Bill