View Full Version : Mach lathe spindle speed control

19-05-2014, 11:24 AM

Has any body managed to conquer the PWM spindle speed and pulley ratio section in version ******66, sure has me confused, and its not helped by the manual bearing little resemblance to this version of the software.


19-05-2014, 02:57 PM
What exactly is the problem. I'm not having any trouble setting up PWM for router spindles with latest lockdown.?
What is doing the PWM.?

19-05-2014, 06:01 PM

The problem is trying to enter the different pulley ratios, not that I'm sure they would do anything if I succeeded. It seems that the best one can do is to run the spindle at max PWM then set the actual spindle speed to the same which then equals commanded speed and tolerate errors at slower speeds. It's not helped by the manual being written for an earlier version with different screen sets etc.

I suspect these problems are peculiar to the lathe version as there are many other oddities and annoyances.


19-05-2014, 09:24 PM
First off, .057 is the latest recommened version for lathe.

What exactly are you trying to acheive with the pulley ratios?
Unless you are actually using different pulleys/ratios, then just set them at 1:1.

The spindle calibration doesn't work, and hasn't for a good while, so you just need to tolerate speed discrepencies, unless whatever controller/spindle control board has any adjustments to tweak the voltage v speed.
Mach Lathe does do the job, but it does have various quirks, and pretty much highlights why Mach4 is pretty much a complete re-write.

20-05-2014, 06:44 AM

Thanks for your reply, the Mach3 lathe version that downloaded in February and which I'm using, is R3.043.066 !

What exactly am I trying to achieve with pulley ratios, well I'm just following the manuals recommendations. As there are six pulley ratios available on my lathe it seems to make sense to have them installed and ready.

It does not seem unreasonable to me to expect, that after marketing this product for so long, the company would have at least amended the manual to reflect the software version that is downloaded. And no, I don't buy the argument that it's free so take it or leave it, as it's not free when one has purchased a licenced copy.

Having many years experience with Fanoc, Yasnac, Haas and Mitsubushi controllers, I'm not impressed, Mach3 lathe does not even support G70 G71 G72 G73 which are fundamental to any turning operation.

Rant over.


20-05-2014, 08:47 PM
I know certain turn things got broken after some mill stuff got fixed in the .066 version, however I can't remember what they were. Turn has always been the poor relation with Mach3, as it's got very few users compared with Mills/Routers.

What manual are you reading?
I've got the one named Mach3Turn_1.84, and the only things that have changed are the number of pulleys allowed has increased from the 4 mentioned in the manual to 15, and the pulley configuration is no longer under the spindle set-up tab, but has it's own option in the Settings menu. Other than that, it still works the same.

Essentially, configure your spindle motor output so the motor runs at maximum speed, then set min/max speeds and ratios for all the pulleys you want to use. Then Mach will display an error if your commanded speed exceeds the currently selected pulley.
Remember it will be upto you to manually select the pulley in Mach that matches what one you have engaged on the lathe!
Also, even though Mach can display an actual spindle speed (STrue), it does nothing to close the loop. It only needs the actual speed to sync the z-axis for threading moves.
I actually just had a quick search of the mach support forum, and the spindle calibration does work, but it's advised not to play with it! - spindle calibration (http://www.machsupport.com/forum/index.php/topic,23468.0.html)

G70-73 are only fundamental if you're used to using them. The turn wizards will create the required g-code for the non-profile moves.
You've got to consider how much Mach3 costs in comparison to the controllers you've mentioned.

21-05-2014, 07:37 AM

Thank you for your reply and your brave effort trying to defend the indefensible. There is an old and wise saying " To pay too much is to waste a little, to pay too little is to waste the lot", I appear to have wasted the lot!

Please try and find find someone to demonstrate G70-73 to you, perhaps then you will understand how truly impracticable wizards really are.


21-05-2014, 08:34 AM

Thank you for your reply and your brave effort trying to defend the indefensible.

No your wrong.! There's nothing to defend. You didn't buy Mach3-Turn they gave it you FREE when you bought Mach3 Mill.!! That's what you paid the license fee for.! . . . . If you had done some research or asked you would have seen Lathe is no longer supported and hasn't been for a very long time.!

$175 the price of Mach3 mill will get you 15mins of a Fanuc's engineers time if your lucky but the Guys at Artsoft will give you pretty much unlimited free support if done correctly even to the point of even writing special code just for your problem if needed( That's how Mach3 got in the mixed up state it's in now) so please don't whinge and try to compare Mach3 to Fanuc controllers and software that cost's 1000's to buy and 100hr service charges.!!

Lets compare apples to apples and unless your a GEEK and prepared to go down the linux route then nothing comes close to Mach3 MILL for the money. If you want lathe then NO don't buy it because it's NOT FOR LATHES.!

So that said when it comes to Lathe then your actually better off going with Linuc CNC so go whinge over there.!!