I am a PhD student at the Biomedical Genomics Lab at the Institute of Biomedicine of Barcelona. 

I am using ChimeraX to produce figures for the publication of an in-house recently developed tool for cancer driver gene discovery.

I am new to using ChimeraX, so I am sorry if my question might seem very naive to you. Anyway, I can't find this information anywhere else.

My problem is simple: I want to show the surface (or volume) occupied by the atoms of a selected number of residues within a chain.

I can easily achieve this by using the Gaussian surface (GS) by adding the parameter "resolution" to the "surface" command as "surface :10-20 resolution 6"
The problem is that the surface visualized in this way has "gaps" where it overlaps with other atoms that are not from the selected residues. 

As expected, these gaps get larger when using a greater resolution. Now, I would like to show the complete surface around these residues, without gaps.

Could you please provide any suggestions?

Thank you in advance, and best regards,

Stefano Pellegrini