Tom from SWISCO responded:
July 27, 2018
Well, let's take a step back. I'm not sure if you mean your shoe is 1" side to side, or front to back. You have a Series 351 balance (S351-31) if your shoe measures the same as the 1" shoe shown below. As far as the weight, a "30 5" balance would usually be rated for far less than 50 pounds; more like 28 to 32 pounds. Before considering any change in the spring strength, weigh your window and compare to this chart. Your "30 5" is the modern "3050."
|