Dear Lisandro Otero, Sorry, you cannot change the coil thickness only for a specific part of a model. It always applies to the whole model. "The subcommands cartoon style and cartoon tether control per-model settings": <https://rbvi.ucsf.edu/chimerax/docs/user/commands/cartoon.html#style> However, you could try opening an extra copy of the same structure, and then showing only that loop in the second copy. E.g. if you wanted to do this for the coil at residues 245-252 of structure 2mnr: open 2mnr open 2mnr hide #1:245-252 targ ac hide #2 & ~ :245-252 targ ac cartoon style #2 & coil thick .8 Meaning: open two copies of structure (model #1 and model #2). Hide residues 245-252 of #1, both atoms and cartoons. Hide residues except for 245-252 of #2, both atoms and cartoons. Make coil of #2 cartoon thicker. You can see #2 is a different color than #1, but you can make it the same color, e.g. color #2 & C tan targ ac I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco

On Oct 18, 2021, at 9:47 AM, Lisandro Otero via ChimeraX-users <chimerax-users@cgl.ucsf.edu> wrote:

Dear Chimera developer;

How can I change the coil thickness in a specific loop in ChimeraX? I have tried with the Hierarchical Specifiers but I was unsuccessful? Could you please give me a command line as example? I'm using “cartoon style coil thickness XX”

Thanks in advance.

Best.