Mach2 and mach3 have different results.

[alexccmeister]

Hi All,

Just want to ask if anyone of you came across this problem. I have been testing my stepper motors with mach2 and thought it worked fine until I downloaded mach3. My motors seems to run more realistically with Mach3 than it is with Mach2.

One example, when I run the g code to drill holes in a circular pattern, the z axis seems to run faster when using mach3 and in mach 2, the same z axis turns in steps and it is really slow. Is this due to a setting problem? I thought running both mach2 and mach3 should yield the same result. Apparently not. Anyone can help? I am using demo version for both. Thanks in advance.

Alex

[turmite]

Hi Alex,

While I don't have a lot of experience with Mach3 I have run Mach2 for 3.5 years now and have been very satisfied. I have Mach3 loaded on my machine and use it for digitizing and I do know that the tuning is much different for 3 than it was for 2. If 3 is running much better than 2 I would simply suggest you stay with 3.

Mike

[ger21]

I'd expect Mach3 to run a bit better, as it's a much improved version of Mach2. If all the settings are the same, you should get accurate results with either one though. Are you're CV settings the same?

[alexccmeister]

Thanks Mike.

Gerry, What is a CV? Sorry 'warning' Newbie here. Yes, I am thinking the result should be the same for both. But when I run with mach3, the turning of the z axis motor is more representative of the leadscrew turning a proper distance. But with mach2, the z axis motor was like stepping twice every second. You wouldn't see any reasonable linear movement from this at all.

Did I miss any setting in mach2? Thanks.

Alex

[alexccmeister]

Hi,

I managed to get a few things working with mach3 demo. But I am still having trouble getting the motor to turn correctly. At times it will turn the correct amount of turns corresponding to the length of linear travel as per the G Code. If I am correct, for a 4 inch travel, the motor should turn 80 times. At time it is but sometimes it is less. Funny. Anyone can help to explain where I am going wrong? Thanks.

Alex

[ger21]

Try lowering the acceleration and velocity by half.

[alexccmeister]

Isn't the acceleration and velocity control the speed at which the motor runs? If thats the case, then if I reduced the speed, the DRO will also show a reduced velocity of the read out, i.e. the numbers changes slowly. But the problem I am having is that on one occasion, it runs properly but then on another occasion it doesn't. Never realised there are so many uncertainties when using mach software. Or maybe just my setting not right.

[turmite]

Gerry I don't know about all situations, but in my own, the tuning was different between V2 and 3. Now that may have been due to the new set-up being slightly different as well, but my number would not work if I simply translate them across to the new xml.

Mike

[turmite]

Originally Posted by alexccmeister Isn't the acceleration and velocity control the speed at which the motor runs? If thats the case, then if I reduced the speed, the DRO will also show a reduced velocity of the read out, i.e. the numbers changes slowly. But the problem I am having is that on one occasion, it runs properly but then on another occasion it doesn't. Never realised there are so many uncertainties when using mach software. Or maybe just my setting not right.

Alexccmeister just remember that birthing always has pain, but the result is joy! For the money, you cannot find a better deal than Mach software. The support is #1 regardless of who you want to compare it to!

Can you be more specific on what you mean by the above quote, "But the problem I am having is that on one occasion, it runs properly but then on another occasion it doesn't." Are you meaning the machine runs at programmed speeds one time and then the next time runs as some other speed? Do you ever see changes within the program?

If you are getting good results some of the time but not others it is typically something causing problems with the pluse train or noise but if I remember correctly noise normally causes lost or gained pluses to the motors.

Do you have sreen savers? Gerry you would know more about this than I but could it be a program interferring with the pluse train?

Mike

Mike

[ger21]

The reason I said to lower the velocity and accel was that perhaps you're trying to go faster than the machine is capable of and you're losing steps. Go much slower and see if it helps.

But, if Mach3 works fine, get rid of Mach2 and don't worry about it. That's the easiest solution. There's really no reason to use Mach2 over Mach3.

[JOHNKLEEPER]

You Are Loosing Steps I Concur The Feed Rate In The Motor Tuning Dialoge Is Set To Hight Use The Motor Tuning Dialog To Set The Fed Per Inch To A Very Low Setting And Keep Incrementally Bumping It Up Until No Steps Are Lost.

[alexccmeister]

I got all the stuff sorted out.thanks for all your help. I managed to get mach2 and mach3 to run properly. I set the velocity to 60 and acceleration to 3. Thanks.