Messages

371

General Mach Discussion / Flat bottom Hole

« on: December 29, 2017, 03:07:54 PM »

Need some recommendations how to drill a flat bottom hole on a lathe.  I have a .375" x 1.75" hole.  I peck with a 118 degree twist drill to 1.75.  So far have tried using a .375 2 flute end mill pecked from 1.6" depth to get the flat bottom.  The end mill fills too quickly and the spindle over torques and shuts down.  The end mill is not creating chips but rather dust.  Last effort was  s700 f.25 peck of .05

What approach should I take instead?

TIA

RT

372

Mach4 General Discussion / Home Signal

« on: December 29, 2017, 11:28:46 AM »

When you set up a motor you define a home signal pin and whether that motor homes.  Is there an api that will allow you to turn on/off, mapping enabled or input name?

On my lathe I have my spindle configured to be either run by a motor for the spindle function or alternately driven by a stepper (belt change, motor 3, drive C) to act as a rotary/indexer.  I use input 12 as the spindle index pulse and as the homing signal for the C drive.  When used as a spindle the C drive homing signal is sent on each revolution.  It doesn't affect performance but the log has a message sent for each revolution.  I know I could just use two profiles but that creates other issues (re-referencing all axes).

TIA

RT

373

Mach4 General Discussion / Re: Mach 4 Feature Request

« on: December 23, 2017, 07:33:01 PM »

Would be nice when using the manual tool change ( mcCntlToolchangeManual) to have the tool number requested and Tool Description of the tool displayed in the dialog box. 

MTCW

RT

374

Mach4 Videos / Re: Mach4 and Coroutines

« on: December 18, 2017, 11:29:25 AM »

What Craig said, exactly!!!

Thanks!!!

Any difference running one from a module or macro script?

RT



RT

375

General Mach Discussion / Re: Z axis loss of cutting depth after multiple Z movements

« on: December 15, 2017, 07:58:41 PM »

To determine if you have a loose coupler put a witness mark each side of the coupler and the motor and lead screw where they meet.  If after running the program there is a shift you know that it is slipping.  Also mark where the bit is in the collet and measure the length from the tip to the collet to determine if there is any slippage there.

To determine if you are losing steps due to too much force run the program with no material being cut and see if the z is still 2mm above where it should be. If not then you have eliminated that.

Next search and replace all g0  commands with g1 f10 and run the program and see if the z is still off.  If so then your acceleration is too high.

That eliminates most of the possible mechanical problems.  This costs you nothing but your time.

HTH

RT

376

General Mach Discussion / Re: Z axis loss of cutting depth after multiple Z movements

« on: December 15, 2017, 11:41:30 AM »

I doubt that the Gecko is the problem.  More likely culprits are, losing steps due to too much acceleration, coupler from motor to leadscrew slipping under stress or a piece of material in your collet not allowing the collet to fully close and moving the bit upwards under pressure.  The intermittent stops would be of concern to me as well.  If the computer (windows) is trying to check for something (java update, itunes, windows updates, screen saver...) there may be a loss of communication between Mach, the parallel port and the Gecko.  I'm sure you've already checked all of these things but I would check them again.

HTH

RT

377

General Mach Discussion / Re: Spindle index

« on: December 15, 2017, 11:29:31 AM »

When you say the diagnostic screen shows an inconsistent index pulse are you referring to the LED?  If so you  need to disregard that, it can't update in real time.  Does the actual spindle speed DRO remain relatively constant?

378

Mach4 General Discussion / Re: Mach4 tooltable

« on: December 14, 2017, 10:05:50 AM »

Just a thought, were you in tool #2's offset still when you measured tool #3?  All offsets need to be relative to #1.  I'm sure you know this but if perchance you forgot to reset to tool#1 before measuring too #3 this would be the result.

TIA

RT

379

Mach4 General Discussion / Re: mc.mcAxisSetMachinePos

« on: December 11, 2017, 12:03:06 PM »

I can think of one scenario where you would want to set the machine pos manually since I am the one trying to do it.

I am using a small lathe. Since some of the time I use the tail stock and some of the time I don't. I don't have any spare inputs to add more separate homing switches at fixed positions so it would be easiest, for me, to use my probe attached to a fixed length rod inserted into the spindle and another rod inserted into the cross slide to home the Z axis.  I am using a pmdx 411 and when I home the Z using a signal (ISIG_INPUT10 same as the probe) the overrun pushes the rod back into the spindle, about .040.  If instead I use a g31 it stops with acceptable overrun (read, it doesn't affect the probe fixture).  At that point I would like to make that machine origin for Z.  Then I move the x axis to each side the rod and g31 each X+ and x- so that I can determine where the center line is on the x axis.  This negates having the exact rod sizes and can be used with any drill bit or other tool that needs to be on the center line. Making this the x axis machine 0 would allow for easier (in my  limited tool setting knowledge) to calibrate all tools to this point using the probe with each tool.

I am trying this morning to use the 'home in position' to do this but am running into the usual problems with mc.mcCntlMdiExecute, mc.mcCntlGcodeExecute, mc.mcCntlGcodeExecuteWait and mc.mcAxisIsStill problems.

Is there a list of other API's that no longer work so I don't waste hours trying things that are known to not work anymore?

TIA

RT

380

Mach4 General Discussion / mc.mcAxisSetMachinePos

« on: December 10, 2017, 04:15:25 PM »

Isn't this supposed to set the axis machine position?  When I run this from a button script the z axis dro machine pos does not get set to zero.  Is it doing something else that I am misunderstanding? The return value is 0.

wx.wxMessageBox(tostring(mc.mcAxisSetMachinePos(mc.mcGetInstance(),mc.Z_AXIS,0.0)))

TIA

RT