La fonderie de Yan / Yan's foundry

Mon interface CNC pour le tour Gingery
My CNC interface for the Gingery lathe

I've been dreaming about it for years, thinking it was really too expensive and complex for me.
I decided to prove myself wrong and build my own after finding nice simple controler plans.
Since I'm building the lathe, I tought I could automate it on 2 axis as well!

I elected to use this circuit from CW Tech and chose to build it myself only for 2 axis.

I had:
I needed:
I bought the parts and waited, then put everything together and here is the result:


Here is a bit of a pictures story. Make you dreams alive, it's possible!

Here is a case I found. It had this hole on the face so I put this computer lock key I salvaged.
This will keep kids and wanderers from starting this thing and breaking it.



Here is the back of the box after intalling the power input and parallel port.
Both parts come from old computers or the parts bin.



My old pentium 233mmx with 128 mb of RAM, 6 gig of hard disks, cd, parallel port card and network.
It is pictured with my box, the power supply and the cabling. This has not cost me a penny yet!
Plenty enough, for it's cnc purpose and sufficient for other tasks as it will be installed in the garage



Here is the board I made. The chips and the diodes are missing but I had to order these rare ones...
Okay, the green-gray bus is the parallel port input, the antenas are the home switches.
At its right, the jumper bus taken from and old PC and the resistance pack. Then the chips heat sinks.
I found those in a computer as well as the 7805 voltage controler heat sink in the back.
The 7805 was found in a PC power supply. The numbered bus are the motor output bus.
4 coils + common ground. The little black block behing them is the + - power input terminals.



Here is the back of the board, it has strips of copper you can use and cut to separate from other parts.
I really sucked at soldering at the beginning, been so long, but the twist got back quick.



Here is the case with the board fitted. Now waiting for final seembly at which I will add a 5A fuse.
I fitted 2 home switch on the front face of the case. The box has a ground in the back that I will use.



The chips have arrived! Shipping and custom really killed me here... at least double the cost!
The diodes too have arrived, no problem there. So I build the thing.



Here you can clearly see the parallel port wires and block at the left, top is the fuse.
At the right are the motor ouput blocks, higher the power input block and 7805 controler.
In the center are the reverse diodes and left to it the UDN5804B chips and resistor bridge.
There are also resistors for the input circuits which you do'nt see.



And here is a story about troubleshooting a circuit:

Here is how I made it after everything got together.

I assembled all the parts and chips sockets, but did'nt install the chips in them, I carefully checked for shorts between each circuits. All seemed fine. There are just so much. Then I put some power in there... the 5 volt from the 7805 is there, nice. So I say, let's try one chip, that one I extra that I ordered for tests. It's in, but I check voltage on it and there is nothing... hmmm.... so I check my circuits, geee... I forgot to solder this wire... Here it goes, everything back in.
Now I have voltage but it's about 2 volts instead of 5v... strange, I check the heatsink of the 7805 with my thumb and I burn myself badly... shut the thing off, fast! So I check again for shorts, I think I migh have got it cause the short disapeared. Again, I put everything together and power-up the power supply. Here I have 5 volts... and the chips is cool, the voltage controler is cool... That's cool.

Let's put a motor and the computer to it. I hook one stepper, looking for central taps and all. Then I start turbocnc. In turbocnc, there is an option called "ports" (F2). If you set it to Active (Alt-F2), you can check the "pin usage" or "logic level" display (select with Ctrl-F2) or your paralell port and look at you INPUT ports receiving data and if set-high or low.

But I wanted to know if I could run the motor. It happens that you can also generate OUTPUT by pressin the pin number on the keyboard. Ok, so there I press on the #6, step pin for X-axis. The type-matic of the computer bios makes it repeat at about 40 times per seconds and there my motors goes for a run... I press the #2 key for direction and again the #6 and it goes the other way! As Tim (abymc.com) would say, W00T!!!!

Okay, so I slap the other chip in and plug the other motor the same as previously. Again I turn the power on and try the other motor and controler with the ports options...All of the circuitry works all right, the motors turn and change direction and heat just a bit. When they are power locked, it's a pretty stiff stance!

I make myself some simple g-code to test it and launch it... nothing... So again I go in the options, reverse the pins for step and direction for the X and Y axis, and try this... Now I have 2 nice vibrators but that's all... Okay, I turn down the frequency thrown at the motors down at max 300HZ since these are cheap motors (3$) and try again.

It works! IT WORKS! This was a blast to see both motors go in sync. The motors have a nice little torque which should prove adequate for the gingery lathe. I made it all for around 50$ CAN and a big dig in my bin parts.

The motors are yet to be mounted on the yet to be finished lathe but it's getting there. When the sand will stop freezing, and the sand will be good working, the lathe will get alive.