Series 600 Spiral Balance Conversion

Hey, Frank. I'm not really sure that I understand what you need. The Series 600 is an updated design, itself. They haven't really changed how this balance works in a long time. What exactly are you trying to do?

That's funny, people usually recommend the opposite. Either way, I'll tell you what I usually tell others who are considering this kind of project: spiral balances and coil balances are not designed to be interchangeable. That said, it is sometimes possible in certain circumstances. 

Before I recommend anything I need to tell you that our company always recommends that you stick with what you have now. Speaking only for myself, I think that's a good policy. It's a lot easier and will save you any potential headaches further down the line. If it ain't broke, etc.

If you still wanted to use a coil balance, then I'll need more information from you. To start out, please tell me the width and thickness of the pivot shoes your window uses now. Please also show me a picture of the pivot bar that interacts with them. That will allow me to determine whether any of our coil balance shoes will work in their place, which is probably the most important deciding factor. If we can find a pivot shoe that fits then the rest should fall into place.

Sounds good to me! Most customers I talk to actually despise their coil balances. Even some of my colleagues do. In most cases it's because they're more difficult to replace, but in some cases there's the (mistaken) idea that they're not efficient. I disagree; I personally like coil balances, but people want what they want.