Oops lost machine coordinates can anyone help?

[dme2637]

I shut my machine off which is run with a smoothstepper after drilling some holes in a large workpiece that I still have things to cut in. When I shut my controllers and smoothstepper off the only way I have been able to get things back up to communicate is to restart mach 3. So basically I'm sitting right now with my computer thinking and I have my machine sitting still with the coordinates still up on mach 3 but everything is locked up because my smoothstepper was shut off. How can I return to Z?

Thanks!

[dme2637]

I'm sorry return to Zero

[metalworkz]

Hello,
If you reference the machine each time you start it and it accurately homes the machine axis(X, Y, Z),then you should be able to power off Mach and get back to your start point to do the remaining toolpaths. I would check the Z zero setting to be sure it is correct as well as try and be sure the X and Y are right. If you set your zero to the corner of the blank you can just MDI the machine to X0.0Y0.0 (G0X0Y0 in MDI line and hit enter[make sure Z will clear clamps etc])and make sure it lines up with the corner. This is one of the main reasons to reference the machine each time, that way if something happens and you need to restart you should be able to come back to the home position and restart.
When you normally shut down Mach will ask if you want to save the fixture, and if you plan to come back to the same zero and or do more work from that zero this option will help you get back to the same point. Since you did not get to save the fixture you should verify that you are at the same zero settings and that the Z is set to the right height.

[dme2637]

I failed to reference all home when I started. If I know my last coordinates say x12 y12 couldn't I restart software zero point where machine is manually enter x-12 y-12 and end up back at my original zero? On another note when I go to the MDI tab and try to enter the number the green x coordinate portion will highlight allow me to enter my own number but as soon as I highlight y x returns back to its original number.

[metalworkz]

If you know the coordinates of a feature on the part that is already cut, you could try restarting and enter those coordinates with the Z raised and move to that position and verify that the tool lines up when at that position. This is not a very accurate way to get back on track but for some work it make be sufficient to get a part finished. If the tool does not line up then I would think you can line the drill up with the hole and then enter the correct coordinates into Mach if you know what they should be. This might get you back to the correct positioning. I have never had to do this but if you don't have another way to find the zero then the holes that are cut should be a good way to get there since you say you know what the coordinates are. Remember when you enter the values for the hole coordinates into the Mach display to hit the enter button for each. Hope this helps and gets you going again. In the future before you shut down Mach you can find in the menu the 'Save fixture' option and possibly get you back to the start point a lot easier, and referencing the machine each time you start is a good idea for these reasons too.

[kilrabit]

Jog and put the bit in one of the holes that you have already drilled. Find that hole in your program you drew the piece with, put your mouse over the center of a hole and you will see coordinates.
Type those coordinates into the X and hit enter then the Y and hit enter, then you can rezero and you should be good.

If that is a USB smooth stepper... throw it away... and get the ESS smooth stepper, which is ethernet, you will save money, and blood pressure spikes.
The USB smoothstepper is a good piece of electronics .... the Problem is Microsoft Windows and how it interacts with USB.




Roy

[martin54]

I'm not sure I fully understand what you have done, if the co-ordinates that are showing in Mach3 are correct for where the spindle should be then you can just press go to zero to return machine to it's original start position.
If you have lost steps or the co-ordinates have changed then you would need something to reference the machine like the drilled hole that has been mentioned. When you type in co-ordinates you have to hit return for them to take effect.

[martin54]

On a side note you don't have to reference your machine everytime you switch it on, the machine co-ordinates will never change unless you hit a stop or loose steps. if all you are using is the G54 command then this will be what your 0,0,0 will be. By referencing all home & then pressing go to zero you should end up at your original starting zero. As I said before though that is as long has nothing has happened which could have changed the co-ordinates.

[ger21]

On a side note you don't have to reference your machine everytime you switch it on, the machine co-ordinates will never change unless you hit a stop or loose steps.

Actually, when you power up your steppers, they will tend to move to the nearest full step. If you shut the machine off in a microstep position, then it will restart in a different location. This amount can be very small, but the cumulative affect could be quite a bit after several times.

[zeeway]

I have often wondered if my machine "drifts" in an emergency stop. Per Ger, this seems to be only about a half thousandth of an inch max unless there is additional looseness in the machine from backlash,coupling slop, flex, etc. I am paranoid enough that I always try to start a job by homing my machine.

Angie

[rscrawford]

Its a good practice to home the machine every time you turn it on, and if you are running for a full day, maybe a couple times during the day. Especially if you have stepper motors, which can lose steps without you noticing. This practice solves a lot of headache. Then in a situation like this, you can just restart everything and you know that when you home the machine your positions will be accurate again.

[martin54]

Angie, it could depend on a number of things to do with just the motor tuning itself never mind the backlash, slop etc

I probably phrased my reply badly, yes it is good practice to home your machine each time you power it on & yes it is the first thing I do, well second actually. I don't have a homing switch on my z axis so I manually jog the z axis up to a mark I have made before homing the machine. Closest I can get to homing the z axis at the moment, I need a board with more inputs than I have at present.

Point I was really trying to make to the OP was that if he had forgot to home his machine before starting work then it wasn't necessarily the end of the world.

[metalworkz]

Not to highjack the thread, but Martin are you able to wire the home switches in series? I know with my USB smooth stepper we were not able to use the home switches to REF ALL Home but could home one at a time when in series. I believe we rewired them in a parallel configuration and it will REF ALL now but it takes more inputs as you mentioned. With a regular BOB like C!0 etc. I have had good luck wiring the Home switches in series. I know sometimes this is not an option and maybe you have already tried this etc., but if using 2 inputs for the X and Y currently then wiring in series could free up one of them while putting them all on a single input. Just a thought.

[dme2637]

I ended up finding the closest 1/8" hole lined up bit and used MDI tab to place new coordinates on my machine. It worked but I could see where I could lose accuracy in a more precise toolpath. I'm still a little confused about soft limits etc. If I let my machine hit my homing switches and find its own 0x, 0y, then zero the machine to the corner of my work piece then lets say I have a power failure? Do I need to write down the distance my machine is off machine coordinates every time to go back to my work piece zero just in case?

[IslaWW]

"Do I need to write down the distance my machine is off machine coordinates every time to go back to my work piece zero just in case?"

This is a product of your machine control software. Some systems will remember (store) user XY zero coordinates, some won't. But it is better to be safe than sorry.