ADi...the KR20 rail is already pre-loaded, so the "light" spring you have shown won't help in reducing motion. It will slightly raise the resonance of the system, but it's doubtful this will be much of a benefit. What it
will do is to create a constant torque on the poor KR20 carriage, resulting in premature wearout.
The "strong" spring likewise would only help if you had a
very heavy system you were trying to move, but the KR20 can drive heavy loads, so the usefulness of that spring is questionable.
Rik linked to a recommended idler rail implementation I shared for the KR15 system, and this can be applied to the KR20 as well. I did this for a vertical setup which ended up with another forum member, based on the WeMacro vertical system. This implementation offers several improvements vs the rail by itself:
- constrains the system on both ends so no low frequency resonances, allowing faster settling times
- reduces moments, which improves rail life, and greatly reduces amplitudes of any movements (stiffer system) caused by environmental disturbances
- constrains lens end so rail movements don't translate to the image
With the system you have shown, I'd expect settling times of >1sec, and even after settling of a major disturbance, the system may continue to move for much longer at lower amplitudes which could have impact on the image. With the idler added, I'd expect settling times <100msec, and once settled the residual movements to be small enough to not cause impact on IQ.
Here's the modified WeMacro system:
