How do you clean the dust and other stuff that seems to collect on your rolling stock and locomotives while they are on the layout ?

I just received my new subframe for my old 4-6-0.

I am trying to figure out how to make curved handrails; specifically, the handrails that top a metal grain storage silo.  The prototype was located at the end of the Santa Fe's Eden branch, it was literally the last structure on the line, and was composed of fifteen metal silos; all with what appears to be 2" to 3" pipe handrails lining the top.  That is my guestimate; it appears that the stanchions and the railings were of the same material.  Lots and lots of things in West Texas are made out of surplus/repurposed oilfield pipe, 

As a head's up, Autodesk's Fusion 360 is changing its terms of service (again) for free-to-use hobbyists. If you pay their yearly subscription ($500 per year, $300 on their sale), then these changes will not affect you.

Most of the changes can be found here: https://productdesignonline.com/tips-and-tricks/the-fusion-360-personal-use-license-is-changing-september-2020/