Wood Window Balance

Question

The metal tube ONLY is 33" by 1/2", tho the rounded half round groove in the wooden sash is 5/8". There's a whitish plastic piece at the bottom. The spiral is attached to a metal bracket on the bottom of the sash. See photo.
I can't find any number stamped on the tube.

The sash simply goes up and down within the trim. Not tilting.
There's a 1/2" exterior diameter balance that is 33" long or at least a tube with balance inside that is nailed at the top. The wooden sash has a 5/8" half round groove on each side. Possibly a 5/8" tube would fit, but would be tight. A spiral metal piece extends out the bottom.
There's a whitish plastic piece the spiral metal piece comes through and it is pinned to a metal bracket attached to the bottom of the sas

comparing with Product Code: S500-33.
The plastic color coded plug seems to be white?
What sash weight does that indicate?
Also, there's a bracket on the bottom.
Is it possible to try a side clip?
Any difference in how these attachments (brackets or clips) will work?

Tom · Accepted Answer

This is a very old spiral balance. Your exact model likely isn't available, but I feel pretty confident that our S500-33 can still work. If the channel where the balance installs ends up being too small then you will need a way to give it more room. That said, I doubt that will be necessary.

Your bottom bracket looks like it might be in good condition, so it could be reused. If not you can always use our 17-012 as an alternative. I wouldn't use a side clip in this scenario. You want to stick with what you have as closely as possible. These brackets are easier to work with than a side clip, anyway.

As for the color tip, this is what indicates the calibration of the spring. Your balance is quite old so I wouldn't trust it to line up with our more modern color options. Your next step should be to weigh your sash on a scale and refer to the chart on our S500-33 store page to verify the best weight option.