balance weight

Question

I am replacing 25inch and 29inch balances and can not find a weight stamp on the balances. The series 370 appear to be correct balance. The un-tensioned spring on the 25 inch balance is 7 inch; a total length of 18.5 inch from the pin holding the block and tackle and the pin holding the end of spring. The un-tensioned spring on the 29 inch balance is 12.75inch; a total length of 26.25 inch from the pin holding the block and tackle and the pin holding the end of spring.

Tom · Accepted Answer

I'm afraid knowing the size of the spring doesn't tell us anything. If you have no stamps on the old balances to reference, you will need to weigh your sash on a scale and refer to the weight chart we have for both the S370-25 and S370-29.