Centroid CNC4

tpwjayson wrote:

There is a line that ends in an M6 command followed by S3000. I am pretty sure its a command for a speed change but I can't get the machine to accept it as a manual input.

It is an S3000 on one line, followed by an M3 on the next.
I don't know why it is split like that, but M3 is "spindle clockwise" and S sets spindle speed.

[Image]

Nothing there looks clever enough to control spindle speed.

tpwjayson wrote:

What do I need to figure out to be able to have speed control on my spindle then? I am sure its more that a $40.00 control board.

Does S3000 M3 work?

Also I have been wondering about my serial connection. I have a 9 pin going to a 25 pin. Am I going to have problems with this once I switch to EMC? It seems to work just fine for the controller I have, but if I need to get a PCI card or something its no big deal.

EMC2 doesn't use Serial. It sometimes uses parallel.

I think you might still be unclear what is what in your system.

Currently (I think) you have a PC which drip feeds G-code (Serial DNC) to the Centroid Controller, which sends some sort of signals to the Drives, which control the motors.
So, that is PC --(serial)--> Controller --(unknown)--> Drives --(Volts)--> Motors

If you want to convert to CNC then that replaces both the PC and the Controller. EMC2 is the controller, running in a Linux PC. It will communicate with the Drives through some means as yet unknown (hopefully a simple +10 to -10 signal, for full-speed forwards and full-speed backwards)

You run the risk of taking a perfectly functional CNC and spending a lot of time making it possibly a bit better, and possibly never getting it to work again.

EMC2 ought to be an improvement on the Centroid controller, but it is a replacement for the centroid controller. The data that is currently transferred by the Serial link is just passed between two bits of program in the Linux PC in an EMC2 system.

tpwjayson wrote:

Yeah so maybe I have been unclear with what I am trying to accomplish. I want to completely replace the CNC4 controller with a new system. I am thinking the 203v drivers from Gecko, the C1G breakout board from CNC4PC and a power supply, then using EMC2 to control it.

I would probably keep the existing stepper power supply.

If you want to keep the encoders, and handle spindle speed control, and a full set of limit/home switches (and using encoder index to home is a very good idea) then you will run out of parallel port pins.

For not a lot more than the C1G you could have a Mesa 7i43 ($90). That also plugs into the parport, but gives you 48 IO lines that can be configured in EMC2 to be inputs, outputs, step generators, encoder counters or a number of other things.
However, it doesn't make things any easier to wire, so you would probably then be looking at the matching 7i42TA ($45) or maybe 7i47($69) or 7i47S($79) if your spindle needs an analogue voltage to drive it.

I have not heard any bad reports about Gecko drives, and if they claim that the 203V is bomb-proof I would believe them.

andypugh wrote:

I have not heard any bad reports about Gecko drives, and if they claim that the 203V is bomb-proof I would believe them.

I killed one (or it died from a bad component) once on my plasma cutter, Mariss replaced it no questions asked!

John

tpwjayson wrote:I looked at the Mesa 7i43 and it looks like I will go that route. Anything I should take into consideration before I start ordering components?[/quote]
Don't get the USB-only version of the 7i43. You probably only need the 200k-gate version, but the 400k-gate might add future-proofing.

Count how many inputs and outputs you need and whether you need one or two daughter cards.
Try to determine if the encoders are differential or TTL. you don't need the differential driver cards if the encoders only have one wire per phase.
In fact the encoders don't really add much to the system, other than very accurate homing and following-error detection.