uc100 backlash issues mach 3

[metalmayhem]

I've sent 3 emails and haven't received a reply so i figured I'd post my problem here with the hopes of getting an answer . here is a copy paste of my email

In total I own 4 uc100's and one of you ethernet boards . it is a significant amount of money that I have spent over time and I'm trying to take the time to get them all installed on my mills , but as it stands I cannot trust that your products will work properly on my mills

These have been attached to working mills that have never had any issues while running mach 3 . I've installed the uc100 on each and I am having terrible problems with the axis locking up and losing steps .

It seems the key issue is the use of backlash compensation in mach 3 . If I turn off the backlash I have no issues and the mills run perfectly fine , but as soon as I turn the backlash compensation back on then the axis start to mess up while running the program . These mills typically run a minimum of 50hrs/week and they have been for years and I have never had these types of issues till I connected the uc100 .


I have the up to date driver from your site . I have tweaked every possible setting in mach and the problem is quite persistent . Sometimes I can run the program and it seems fine but after 5-10 minutes one of the axis will stall and lock up or it'll lose steps and position .


The uc100 is supposed to support backlash compensation in mach 3 but this has been a solid struggle on my commonly used mills .
Any suggestions would be greatly appreciated because as it stands I've pulled your products from my mill so that I can make parts .
The kind of work that I run is surfacing molds , backlash comp is extremely important because any amount of backlash will show on the parts and they will look bad .

[cncdrive]

The UC100 can do backlash compensation with Mach3, but it can't do the so called "Shuttle accel" which is a mach3 parameter and which parameter is unaccessible in the Mach3 plugin interface.
So, the UC100 does the backlash compensation always as if the Shuttle accel value was 0.
This could cause problems like yours if the motor runs in open loop (is stepper and not servo) and if the rotational speed of the motor is high enough.
What the shuttle parameter in mach3 with printer port does is it adds a fixed time for decceleration, but since this parameter is unaccessible it is not implemented into the UC100 plugin.

With the UCCNC the backlash compensation works totally different. The UCCNC does not stop the axes when compensating the backlash, but it happens continously like how it is done on industrial controllers.
Also with the UC400ETH and UC300ETH with Mach3 the same continous or in other word stopless backlash compensation is implemented.
So, one thing you could try is to try to use one of those controllers instead of the UC100 on your machine which has the backlash.
The other thing you could try is you could try to reduce the feedrate on the backlash areas in g-code.

[metalmayhem]

I am surfacing aluminum day and night at which the tool path is always changing direction . it's impossible for me to slow down the tool path when changing direction without having to completely slow the whole program . It will also stall out the motors when rapiding from one position to the next . I can't slow down my whole system to accommodate a feature that is advertised to work with mach 3 .
One of these uc100's was purchased before the existence of uccnc and the reason that I purchased it was because backlash compensation was supposed to be supported , I also have a 5th uc100 that I bought around that time that is currently misplaced in a drawer somewhere . I wanted to cross my mills over at one time and is the reason that i recently purchased an additional 3 uc100's .

Don't get me wrong but it seems a bit unfair to claim that a feature like backlash comp is supported when in reality it is not going to work properly with mach 3 .

To change all of my mills over to uccnc to accommodate the 4 uc100's (5th somewhere around here) and the one ethernet board is an expense on it's own . Had I known then I probably would have taken another avenue . As it stands , I have a lot of unusable hardware on my hands because I've pulled the uc100's from my mills so that I an make parts . I know that uccnc has com a long way in the past couple of years and a lot of people are using it , but I've been using mach 3 since it came out , I know it and I trust it

[cncdrive]

If you have that many UC100 controllers that are in the drawer as you said which I take as they are in "original condition" and if you can't use them because all of your CNC machines suffering from backlash then we can help you to return those devices for a refund.
Just drop us an email to info@cncdrive.com about this issue and we will help...

[metalmayhem]

I'm good with that . Problem is that you don't reply to emails that I have sent to that email address . I've sent 4 over the past week plus another thru ebay and you haven't replied once

[cncdrive]

I'm sorry to hear that. Unfortunately I was "offline" several times because of some health issues->hospital etc. so I could not follow all emails recently and we get one about every 5 minutes, so it is hard to follow up on them them when you are offline for a few days, but my collegues are reading and answering emails continously, so it's strange if you did not get a reply.
Send an email to info@cncdrive.com and I'll keep an eye on it to catch it.

[metalmayhem]

email sent

[cncdrive]

OK, I see it. I will reply tomorrow, because it is over midnight here now...

[btbb76]

Hi,

Have this issue been resolved?