Archive for September, 2008

Close Control

Thursday, September 18th, 2008

The opposite of remote control.

So far, considerable time is being spent, finding the Zero position on the work.  Part of the reason has been that the computer keyboard and the machine are about 10 feet apart and my back is to the machine while I am at the keyboard controlling it.  This has led to some body contortions and running back and forth about 10 times to tweak the machine into the X0 Y0 position.

The solution, a pendant!

I found this el cheapo USB numeric keypad at Big Lots $6


Finding that edge

Thursday, September 18th, 2008

When setting up the machine its proved hard to tell where the bit center is in relation to the work.  There is a shroud around the bit and in some instances a brush.  This means lowering the Z axis and then eyeballing from the front and the side, peering under the brush with a flashlight, run back to the keyboard, jog, jog etc…

A while back I found this video posted on Hackaday and realized there was a better way.

I started with a crosshair laser from deal extreme, yes I ordered other stuff too as it was to hard to resist.


Encoders Revisited

Tuesday, September 9th, 2008

Prompted by my friend Michael I decided to take another look at the encoder set up on the OZO machine.

The encoder board, has the spindle signal conditioning circuit mentioned in previous post as well as two SN74LS123 Monostable Multivibrators.  Its my guess that these chips act as one shots, conditioning the signals coming from the encoders.  On the encoder board pictured below, pin 1 is at the top and 22 is at the bottom.  Encoder signals are marked with black connecting lines.