another cnc mill questionaire

[theMPloc]

thanks again. i like BOB when i have my machine ready and its working out the way i want, i will definetly give BOB and emc2 a try! another old pc shouldnt be the problem anyway.

[marzetti]

I don't know how large your machine is or what you intend to cut but you'll probably find that the Easydriver won't give you enough power. I have one here I'm using for testing purposes and I'm finding the .75 A output at 12V will drive my small motor but it has very little torque. It should be better at 24V but I doubt even then it will drive my rig at the speed I need so I'll be building my own driver soon. My CNC router (a small one, 20" x 30" capacity) has 3A drivers and it seems to be adequate.
Good luck!

[theMPloc]

i have my easydrivers connected to a nice 6amps, 24 power supply. when i test my motors they seem to have a lot of power. we´ll see in one or two days.

another question regarding the gcode i create with cut3d: there are a lot of possibilities on how to postprocess the gcode which is saved. it says "The standard list of postprocessor's available in the software are displayed in the pull-down list. Select the postprocessor appropriate to your CNC machine from this list."

for example Axyz (*.nz), Gcode mm (*.tap),  Mach2/3 Arcs (*.txt),..

how can i find out which one to choose or doesent that matter anyway?

[marzetti]

That's a tricky question since you're using the Arduino. The postprocessing is tied to the specific CNC software and they are all a bit different. I would check and see what other people are using for Reprap machines. The next best idea would be to use either the Fanuc or EMC2 postprocessing as they adhere most closely to the "official" RS274 standard. For the basic G01, G02, G03 etc. commands though they are all about the same. Here is a good reference on G code in case you don't have one: http://linuxcnc.org/docs/html/gcode_main.html

[theMPloc]

perfect - fanuc is in the list. wonderful.

[theMPloc]

good morning!

i powered my z-axis. runs with you cncdriver. thats great.

of course i have a question: i know that the easydriver has a temperature security switch, which switches off at 160°. just to make sure: is it normal, that the big chip on the easy driver gets quite hot after some minutes? what i am also interested is, that even if i do not have the sleep/wakeup pin connected, the stepper motor is always awake - is this ok?

[mmcp42]

indeed
if you connect the enable wire to the easy driver two things will happen
a) it will run cooler as it gets turned off when not needed
b) the motor will also get powered down

[theMPloc]

so here is the stupid question: to which pins on the arduino do i connect the sleep/wakup pins on the easydrivers. i tried with the pin 18 (A4) where it says motor pin in the init.pde. i thought that would be an option as when the spindle is on the sleep state would change to wakup state. but then the steppers don´t move a all.

[mmcp42]

yup
I connect pin 18 to the EastDriver Enable pin
works for me

aha I see what you are doing
I'm not using sleep!
I'm using Enable

[theMPloc]

hi again. i will use enable then question: in init.pde it says


#define X_ENABLE_PIN 8
#define Y_ENABLE_PIN 18  // sb8
#define Z_ENABLE_PIN 19  // sb8

what does sb8 mean?

have  a nice day!

ps. maybe today i will have the machine ready

ps2 i ordered BOB

[mmcp42]

I wanted to use just one pin ( for the enable so they are all enabled/disabled together
but while breadboarding it was more convenient to have 1 pin for each
never got round to changing it
"sb" means "should be"

[theMPloc]

Yipppppiiiiiieeeeeh!

i finished my machine today and it is running with cncdriver!

at the moment i "see the light in the tunnel" and i again want and have to send a big THAAAAAAAAANNNNK YOOOOOOUUUU for beeing so kind, patient and helpful to me. you are a great guy!

now i will have some fun with the machine while i wait for BOB. then i will start with emc2 and i guess, i will have the one or another question to you again.

thank you once more and have a nice evening!

[marzetti]

Congratulations! It really is a thrill to see your creation come to life, isn't it? I would like to know more details about your machine. Do you have pictures?

[mmcp42]

glad to hear it's all working

I'd be interested in seeing pictures/plans of your machine as I'm still fiddling with the design of mine...

what did you do about limit switches in the? (or did you just disable them!)

[theMPloc]

of course i will send you some pictures! i found out that i made a design fault on the z-axis which at the moment only can move about 10mm instead of 100. i will fix this the next week.

if you want pictures earlier, just let me know and i make them und upload them asap.

i have some questions about BOB (which will arrive next week):

(1) just to make sure: basically BOB replaces the arduino. so BOB will connect to the parallelport on the pc on one side and connect to the easydriver boards, and endswitches on the other side?

(2) do you know if BOB works with Mach3 also?