Archive for November, 2009

The OZO gets a new Saddle

Wednesday, November 18th, 2009

Its time now to build a custom piece of hardware to mount the router to the OZO.  Research on the web indicated that people were using MDF for this kind of work.  Its dimensionally stable, and easy to machine, though the dust can be kind of toxic. I’ve never worked much with MDF before, preferring real wood or plywood to this glued up particle board.

Being an avid scrounger, however, there where a few pieces laying around the shop. So, I decided to use it as the base material for this build. Since I didn’t have a long enough endmill to make it all the way through the 3/4″ material and didn’t know if the current spindle would be up to the task anyway, I made it the old fashioned way, with hand tools and brute force. First I drew the design in Rhino, then, printed and transferred it to the wood with carbon paper.



A New Spindle

Wednesday, November 18th, 2009

For a while now, I have been debating the stoutness of the spindle motor that came with the OZO.  It is very quite and high speed but seems to lack enough torque to really bite down and make deeper cuts.  The last thing I cut with the machine, oh so long ago now, was thin plywood.  I tried to cut the whole thickness in one pass, and while the spindle managed the chore it screeched and whined and complained the whole time.  Continuing to use it in that capacity would eventually wear it out and break it.  I decided to save it back for finer task, like circuit board milling (probably what it was designed for) and move on to something with a little more guts.

After researching many CNC forums and DIY build write ups I decided on this.



Fake Thermocouple

Wednesday, November 11th, 2009

If you are interested in building circuits that will incorporate thermocouples, its nice to have a low millivolt supply for testing and simulating a thermocouple in a heat source. It saves time and energy, keeping you from cranking up the hot plate or the blow torch. Most power supplies will not deliver the low millivolts needed to simulate a thermocouple in a heat source. This device allows you to quickly sweep to a general voltage and then fine tune to a specific value. It uses one 9V battery as a power source and is portable. Voltage ranges on the course dial are from approximately 3mV to 200mV and the fine tune dial will adjust about 4mV around the initial set point.