UPDATE: @theozimm identified a space
WHERE: Workshop Cafe, 180 Montgomery
WHEN: 6pm-8pm
Bumping up his note here: 
"Hey everyone! So to celebrate 3D Printing Day we are meeting at the Workshop Cafe at 180 Montgomery from 6p - 8p. The hot topic of the meetup will be discussing the Olsson block but we will also be discussing other topics. Bring some recent prints! I will be! We have Ultimaker, Type A, and Zortrax users all attending the event! "
Been talking with Ultimaker operators from the San Francisco area (headed up by the excellent @theozimm) about doing an Olsson Block Clinic on December 3rd somewhere in San Francisco to match the one Iām co-hosting at the hubs meetup at Fat Cat Fab Lab in NYC with @dano on the same date.
Any interest in joining up with the SF crew? Any ideas for a venue and those looking to get together to do an open hubs event somewhere central?
The SF folks would love to match up with others who are already planning to take part in #3DPrintingDay and pitch in on the festivities. We also want to see if we can draw together as many of the Ultimaker operators in the area into one space to hang out, share our latest projects, and meet each other.
And hereās what we have in mind for the Olsson Block Clinic itselfā¦
The Olsson Block Clinic is a chance for those with Ultimaker 2 Family machine to show up with their machines and Olsson Block kits to get their kits installed, and satisfy the curiosity of those with machines from any vendor who are looking for time with machines with swappable nozzles. The Olsson Block installation is easy, so if you have been procrastinating, time to get yours going among good company.
The clinic will also offer peer-to-peer troubleshooting and a few backup heaters and temp sensors at hand as an emergency backup. Prob unnecessary, but we donāt want to slow down your hubs-printing-productivity. 
Again, this activity isnāt exclusively for UM2 operators ā weāll be sharing experiments with alt nozzles, materials, and other topics of interest to those with UM classics and anyone exploring beyond 0.35mm/0.4mm nozzles on their repraps, third party hotends, and other desktop machines. Weāll be demoing (still evolving) slicing tips from the community, talking about advantages/challenges to the various nozzles for those testing printing materials, and more.
If you havenāt hear about the Olsson Block project before, hereās a write up at Ultimaker. It is a community invention created by Anders Olsson that the Ultimaker community has fallen in love with. Consists of a custom heater block that makes it easy to swap nozzles without dismantling the hotend itself. Itās a drop-in replacement for Ultimaker 2 Family machines and can take advantage of a growing third party ecosystem of nozzles from 0.25mm on up to 0.8mm and beyond that are used by projects like the E3D hotend.