Can you snap some pics?

 

This isn't mine but it shows what one looks like before being disassembled. Once the spring has been "tensioned" it's held in place by the winding gear. Does it get a full turn or does it merely engage and gets its tension just from that? I can't tell.

 

Assemble it, nail or screw the gear base to a 2 x 4, hold in a vise and move the arm to see how much push back there is. The way it's sitting there you would think the spring is relaxed or the gear would have come all the way out of engagement.

 

I'm not sure about the spring being relaxed because with the hand crank gear in place, it's nearly impossible to move the arm. It's a very big ratio.


A 2x4 and a vice is a great idea. I'll give it a try.

 

I can obviously be wrong (again :frown). A flat coil spring that thick could be pretty strong.

 

I just measured across the coil spring on mine at mid travel the coil diameter is about 48mm. They are currently wrapped up for storage at that position. I could measure them at each end of the arc if needed.

 

I think you put the spring in place with window track all the way up when you roll down the window spring winds up.

 

You don't need to do any of that. With the spring in place the assembly will look much like this picture. You'll be able to swing the arm enough to catch the teeth in the gear. I don't think it's possible to put a full wind on this spring. Set the spring in place and bring the assembly together, that's all it needs.

edit: I just "unsprung" this one by hand...

 

The spring is there to keep the window from going down to fast.

 

I think cgsheen wins the prize because the spring is too thick and too tightly coiled to for a "full wind."


I guess when I put it all back together I'll set it in place and use the crank and see if it feels "tensioned" enough, and resurrect this thread to share the results.