Arclight  wrote:
> What system does everyone use? Money jar next to the machine? RFID
> accounting by user?

At the moment, money box next to the machine. $10/hr of laser firing time, so setup and cleanup time isn't charged. The controller prints the time on the display during operation, but we haven't gotten around to finding a way to log that data automatically. 

To ease the manual calculation, there's a little time-to-money chart at the bottom of the time-of-cut checklist, like so, printed and attached to the machine:

time min	money $
0.6		0.10
1.5		0.25
3		0.50
6		1
12		2
30		5
60		10

Consumables for other parts of the shop are an open discussion. There's a poster in the electronics room that explains it:
http://i3detroit.com/wi/index.php?title=File:ERoomZonePosterWithMoney.docx

And such things may get created for other parts of the space, pending availability of round tuits.

-Nate-
