John Bowen Synth Design

Initially I thought that the pitch wheel was very stiff and considered how to fix that. Tonight the spring appears to have fallen off and left the wheel with very low mechanical resistance. Fortunately there is a small dead zone around the center position, so Solaris is still usable. However, I have to fix the stiff/missing spring problem some way. Has anyone else had a similar problem? Any suggestions?

Yes, it is stiff. If you're like me you use the pitch wheel for vibrato...