Slide coating has many different trade-offs. In this example the coating window is rather small and modest changes trigger different problems.
First, we reduce the Vacuum a little:
The Bead Height warning comes on to indicate that the bead will probably be unstable - so you'd better increase the vacuum to stop the instability.
By increasing the viscosity from 7 to 8cP the same Bead Height warning appears:
Yet by reducing it to 6cP we get another warning:
As you will find within the TopCoat text, slide waves are instabilities in the flow down the slide, just as water flowing down a window is intrinsically unstable.
In this example, increasing the Surface Tension dampens the instability on the slide:
Now imagine if you had really been coating in this dangerous regime. Without TopCoat, how would you have known what to do to solve the problems, especially when the solution to one problem (e.g. reducing Viscosity) gives rise to another one.
Turning the issue around, TopCoat can enable you to find settings where changes to the key parameters have little effect on the stability of the coating. This island of stability is where you want to be and is very hard to find without a powerful tool such as TopCoat.