Messages

221

General Mach Discussion / Re: speed control of stepper used as spindle motor

« on: April 22, 2010, 05:45:15 PM »

Okay, thanks.

Just to note, the spindle DRO's yellow led flashes, but not a sound from the motor(S5000 on 1 line in the MDI, then M3 on the next). It's on an ncPod; their support don't know anything about spindle control, apparently. Xml attached, I think...

Richard

222

General Mach Discussion / speed control of stepper used as spindle motor

« on: April 22, 2010, 03:47:27 PM »

Hi, I've asked this before in a different (maybe over complicated) way and got no replies, so I'm rephrasing it to get to the point a bit more...

How exactly does Mach3 handle step/dir for a stepper motor used as a spindle?

Under say, an M03 command, does it produce a step signal and direction signal, and have some internal algorithm for changing the frequency of the steps to alter the spindle speed? I assume this would need to be sent through a driver as for any ordinary axis.

Is it just a matter of connecting up a stepper motor as if it were an ordinary axis, but specifying it as 'spindle' in the motor outputs panel? still not sure why I can't make this work

Richard B

223

General Mach Discussion / pins 4 and 8 on ncPod to drive spindle step/dir?

« on: April 15, 2010, 06:53:21 PM »

Hi,

I have a 2d plotter running mach 3 with an ncPod. X and Y axes are pins 2,6 and 3,7 respectively in 'Ports and Pins', and 'pen up/pen down' is provided by the A axis. Originally I was using the Z axis (pins 4,8) to test drive the material deposition pump/pen thing (linear stepper), but decided to control this using the Spindle Speed Step/Dir option instead. So I disabled the Z axis, enabled 'Spindle', and gave it ports 4 and 8 (from the Z axis) so I wouldn't have to change any wiring.

Under the 'Spindle Speed' tab, all is default, except that 'Use Spindle Motor Control" and 'Step/Dir Motor' are checked, 'PWM Control' unchecked. Also. as I don't need delay for a pump, the 'Delay Spin' times are all set to zero; not that I'm sure I understand that this is what it's about anyway.

On entering 'G01 F10 X-5 Y-2 M03' in the midi screen, the X command executes, the Y doesn't (which is very odd), and the light above 'Spindle CW F5' lights yellow, but the pump doesn't respond. Following this with a reset, then 'G01 F10 Y-2 M03' gets the response 'Unknown word where unary operation could be'.

I'm guessing this is a pin number issue, but I don't know if I should be using the 'Output Signals' ports and pin dialogue boxes somehow. Confused, been a long day... This is the information from the ncPod manual:-

Output            Mach Pin #

PWM Gnd        NA      Just enable in Mach
C      Gnd        ***
E      Gnd        1
B      Gnd        3
D      Gnd        2
F      Gnd        4

It says under that:

-'You can select any output/enable you like in the “Ports and Pins”, “Output Signals” menu and set the “Port#” to 1
with the “Pin Number” matching the output you wish to use. For example; if I want to use “F” as output # 3, from the
main menu in Mach I would select “Config”, “Ports and Pins”, “Outputs” tab and check “Output #3. For the “Port#”
setting I would enter “1” and for the “Pin Number” enter “4”.'

I probably have all the information here to sort this out, but can't make head or tail of it at the moment.

Anyone willing to point this out to me?

Thanks,

Richard B

224

General Mach Discussion / Re: .obj file to g code

« on: April 03, 2010, 04:32:09 PM »

Cambam appears to be free, I will investigate it's capabilities for generating tool paths for fairly complex organic shapes, which is what I'd want it for, mostly.

I mentioned Autocad as I know it can convert .3Ds files to a format that is more generally used in cnc work;- .dxf I think... I realised it wouldn't generate me a tool path.

225

General Mach Discussion / Re: .obj file to g code

« on: April 03, 2010, 03:43:23 PM »

HI again,

Just noticed that Cambam uses 3Ds as one of it's import formats! Is it easy to use, anyone?

Richard B

226

General Mach Discussion / Re: .obj file to g code

« on: April 03, 2010, 03:38:39 PM »

Hi,

Thanks Gerry, Cut3D seems to have what I need, but at a price, as usual. I have noticed that Wings3d also exports in 3Ds format, so maybe there's a student edition of Autodesk's Autocad out there, I will investigate. For the record, Wings exports in the following formats;-

Nendo (NDO)
3D Studio (3DS)
Wavefront (OBJ)
Lightwave/Modo
VRML (WRL)
Renderware (RWX)
FBX (on Windows and Mac OS X)
Yafray
Povray
Kerkythea
Collada

Just seen the price for autocad 2011. Oh well...

Thanks again,

Richard B

227

General Mach Discussion / .obj file to g code

« on: April 03, 2010, 01:42:23 PM »

Hi,

I'm new here, and a bit confused about something...

What are my options for converting a mesh model made in Wings3d (a subdivision modelling program) into G-code to send to my 3 axis mill? (When it's complete, that is.) Wings can export in a number of file types, including .obj, which is a wavefront file, I believe. Does it then need to be converted to a parametric solid? If so, what software is good for this?

The general idea is use a 3d scanner (David 3d or Nextengine if one comes up at the right price) to create mesh files to edit in Wings, then output to the mill,  machine up and use.

I hope no-one minds me asking this here, I know it's a CAD question rather than a CAM question, but as it all ends up as G-code, it seemed like a good place to post this.

Thanks all,
Richard B

228

Mach4 General Discussion / Re: New people welcome !! Come in here and introduce your self!

« on: April 03, 2010, 01:28:11 PM »

Hi,

I'm new to all this CNC stuff, but I'm in the middle of converting a proxxon mill into a 3 axis cnc, using an ncPod... I've already got a 2.5d plotter/ printer, which is still being tested, but seems to have few issues so far, so I must be an okay builder after all!

I'm in the south of England, where it rains every day- good to have an indoor hobby round here... I will no doubt ask many daft questions which I should have been able to figure out answers to myself, so I hope you can be patient with yet another noob! I'm running the plotter on Mach 3, non licenced version as I think I can get away with small G code files. I hope; for now anyway.

I'll post my 1st tech question separately,

Ta!

Richard