Messages

3381

Mach4 General Discussion / Re: Mach 4 and cheap 6040 router

« on: December 13, 2018, 02:13:58 AM »

Hi,
to my knowledge there is no Chinese made USB controller that works with Mach4. XHC have one that they claim works
with Mach4 but it doesn't.

I suspect that your controller will work with Mach3 only....and maybe not even then...Chinese controllers are rather hit and miss.

Craig

3382

Mach3 under Vista / Re: Changing stepper motors with more amp draw

« on: December 12, 2018, 12:36:00 PM »

Hi,
when a stepper motor de-accelerates (in fact any motor) it becomes a generator and pushes power back into the stepper drive, the amount of energy pushed
back into the drive is equal to the kinetic energy of the rotor and moving load.

Some drives handle the regeneration phase better than others....it sounds like your original drives were a bit weak.

Gecko's have the best reputation among CNC'ers  but Leadshine  AM822's also have a good reputation at about 1/2 -2/3 the price of a Gecko.

Craig

3383

General Mach Discussion / Re: Homing a machine without limit switches installed?

« on: December 12, 2018, 12:26:08 PM »

Hi,
I use these switches, Omron make almost identical units, both brands are good quality.

I made a little aluminum 'ramp' which attaches to the axis (on a slotted hole for fine adjustment) which activate the roller. It means that if and when the axis overruns
it does not exceed the switches 'overtravel' and damage it.

https://nz.element14.com/honeywell/bzc-2rq18-a2/switch-basic-top-roller-plunger/dp/1525198?st=roller plunger

Craig

3384

General Mach Discussion / Re: Homing a machine without limit switches installed?

« on: December 12, 2018, 11:14:15 AM »

Hi,
without home switches Mach can 'home in place' So what you do is jog to a specific location, maybe bottom right corner with the
Z axis uppermost and then hit 'Ref All Home' and Mach will treat it current location as its home and reference the axes.
This method is as repeatable as you are accurate about jogging to the exact same location at the start of each Mach session.
Never likely to be as good as good quality home switches but....

Craig

3385

General Mach Discussion / Re: AC DRIVE ISSUES.

« on: December 12, 2018, 02:40:53 AM »

Hi Mick,
I don't know.....what I do know is that the drives work better with a line reactor than without one.

Craig

3386

General Mach Discussion / Re: AC DRIVE ISSUES.

« on: December 12, 2018, 02:09:31 AM »

Hi Mick,
Ok those are both good answers, if the EMC filter is recommended and  approved by Schneider.

But why have you not fitted line reactors? They are both approved and recommended and will improve your power factor.

Craig

3387

General Mach Discussion / Re: AC DRIVE ISSUES.

« on: December 12, 2018, 01:07:25 AM »

Hi Mick,
I have a couple of questions:

Why do you have a transformer at the input....is your incoming power supply 250V? These drives are made in Europe for European conditions
so I am bemused that you need anything like a voltage reducing input transformer....or have you Brexited already?

The next is the EMC filters between the contactor and the drives. Do you have specific advice from Schnieder that they are required or acceptable?
As I have said before, not once but a dozen times, you need line reactors NOT EMC filters, unless the EMC filter is specifically recommended by
Schneider. EMC filters tend to have capacitive input impedance and generally a poor choice for a device deriving DC voltage by direct rectification
of the incoming AC, ie a servo drive.

Craig

3388

General Mach Discussion / Re: After 7 years of perfect operation - "External eStop requested" has me shut down

« on: December 12, 2018, 12:53:58 AM »

Hi,
sounds like electrical noise from your spindle.

Is it a router type? Have you ever changed the brushes? If not, when it comes under load the commutator will be sparking a lot
more than it should be....and producing electrical noise.

Craig

3389

Mach4 General Discussion / Re: Non Linear Spindle Speed?

« on: December 10, 2018, 12:18:02 AM »

Hi,
how accurate do you require the speed?

For years I've used manual mills, lathes and drills and used the speed range closest to the desired optimum, and usually not
much worse than 20% off but seldom within 10% either....and all those jobs turned out fine.

Are you saying that because we are CNC machining the speed has to be spot on?

Craig

3390

Mach4 General Discussion / Re: Hybrid Stepper Setup in M4

« on: December 10, 2018, 12:13:04 AM »

Hi,
kool.

Craig