Floating Head Post Code

[IndustrialRec]

Hey guys, so I'm back again with another question. Hopefully simple. Running PMX85, Proma THC, Floating head, Mach3, Sheetcam etc. Currently running Mach3 plasma THC with scriber and backlash compensation... seemed to work best EXCEPT at every touch off location it comes down, doesn't touch, goes back up.... then back down to touch and trigger Z home switch. Then cuts correctly piece correctly. Obviously the problem with this is the added time to every cut. Any possible solutions?? I will post a code sample below.

N0010 (Filename: WeldingCartBase.tap)
N0020 (Post processor: Mach3 plasma THC with scriber and backlash compensation.scpost)
N0030 (Date: 12/02/2017)
N0040 G20 (Units: Inches)
N0050 F1
N0060 G53 G90 G40
N0070 (Part: WeldingCartBase)
N0080 (Operation: Outside Offset, Layer 1, T7: 45 amp 10 guage steel)
N0090 G00 X27.4866 Y2.4458
N0100 G28.1 Z1.18 F19.685
N0110 G92 Z0.0
N0120 G00 Z0.2126
N0130 G92 Z0.0
N0140 G00 Z0.1500
N0150 M03
N0160 G01 Z0.0600 F150.0
N0170 X27.4508 Y2.5370 F100.0
N0180 X27.3610 Y2.5762
N0190 X27.2717 Y2.5539
N0200 X27.2056 Y2.4897
N0210 X27.1808 Y2.4010
N0220 X27.2040 Y2.3119
N0230 X27.2688 Y2.2465
N0240 X27.3577 Y2.2225
N0250 X27.4447 Y2.2454
N0260 X27.5092 Y2.3081
N0270 X27.5345 Y2.3944
N0280 X27.5130 Y2.4839
N0290 X27.4495 Y2.5506
N0300 X27.3610 Y2.5762
N0310 M05
N0320 G00 Z1.5000
N0330 X27.4866 Y0.7149
N0340 Z0.1500
N0350 G28.1 Z1.18 F19.685
N0360 G92 Z0.0
N0370 G00 Z0.2126
N0380 G92 Z0.0
N0390 G00 Z0.1500
N0400 M03
N0410 G01 Z0.0600 F150.0
N0420 X27.4508 Y0.8061 F100.0
N0430 X27.3610 Y0.8453

[sphurley]

What did you put in the post for RefDistance?

[IndustrialRec]

What did you put in the post for RefDistance?

Right now it looks like it is set to 0. I have not changed that or set that..... dumb mistake? haha

[sphurley]

Try 10

[IndustrialRec]

Try 10

Hey, tried running it with that set at 10, it seemed to come closer on the first downward move but still went back up before coming down further a second time to sense..... should i try a higher value number there? Thanks again!

[sphurley]

That post seems to have an issue. I just ran a test and see the same double touch off. Let me play with it a few.

[acourtjester]

That post processor said it looks for a MM input for switch offset, maybe you should look for another post processor that would work better for you.

[IndustrialRec]

That post processor said it looks for a MM input for switch offset, maybe you should look for another post processor that would work better for you.

Not sure what you mean......

[IndustrialRec]

That post seems to have an issue. I just ran a test and see the same double touch off. Let me play with it a few.

Thanks sphurley, let me know if you have any luck. I am trying different things on my end, any suggestions help!

[AndrewMawson]

Surely you need to measure your switch offset then enter it into the post processor. If the PP has no switch offset set perhaps it's bright enough to ask for one in MM ????

[acourtjester]

This is what I mean

MM.jpg

[IndustrialRec]

This is what I mean

MM.jpg

Ok, no reason be a smartass. This is a forum where people ask for HELP in understanding, if you don't want to help me then don't answer my posts. I understand that is my Post and those measurements are in MM. What difference does that make?? That is my question. Feel free to answer without feeling the need to be "Elite"

[IndustrialRec]

Surely you need to measure your switch offset then enter it into the post processor. If the PP has no switch offset set perhaps it's bright enough to ask for one in MM ????

I have already entered my switch offset of 5.4mm in my PP. Is this what you are asking?

[acourtjester]

Yes I was not sure you have converted to MM and I assumed you were using inch measurements
I thought this was an odd value (N0120 G00 Z0.2126) in your G-code

[IndustrialRec]

Yes I was not sure you have converted to MM and I assumed you were using inch measurements
I thought this was an odd value (N0120 G00 Z0.2126) in your G-code

I agree, It is a bit jumbled to use both MM and IN but it is the only PP that I have found that remotely works for my setup.

[sphurley]

I would ask Les over at SheetCam forum. For whatever reason it is putting in a double line of code.

[sphurley]

Now that I think about it the backlash compensation is likely causing this. I would try the one without backlash
I assume in Mach you have BL disabled? and nothing entered in the Z backlash box.

[IndustrialRec]

Now that I think about it the backlash compensation is likely causing this. I would try the one without backlash
I assume in Mach you have BL disabled? and nothing entered in the Z backlash box.

That is correct in Mach I have nothing in the Z backlash box. Do you have a recommendation for a PP that would work better? The only reason I am running this is because it works great with my setup, except for the double touch issue. Thanks

Edit: Also registered for sheetcam forums and will ask my question there as well when I am approved. Thanks for that tip

[beefy]

Who cares about the post processor...........YET. Doesn't matter if it's a post processor for a dough making machine (just trying to get a point across).

What does matter is the gcode it creates.
What matters next is if Mach3 responds correctly to the individual gcode commands.

Understand the gcode - has the PP created correct gcode. Up to the individual if they don't want to learn gcode, their choice.
In Mach3, SINGLE STEP through the gcode.
It's the gcode that tells Mach3 what to do. Is Mach3 doing what it's being told to do. If not there's the problem.

That's how I've always solved problems like these.

[IndustrialRec]

Who cares about the post processor...........YET. Doesn't matter if it's a post processor for a dough making machine (just trying to get a point across).

What does matter is the gcode it creates.
What matters next is if Mach3 responds correctly to the individual gcode commands.

Understand the gcode - has the PP created correct gcode. Up to the individual if they don't want to learn gcode, their choice.
In Mach3, SINGLE STEP through the gcode.
It's the gcode that tells Mach3 what to do. Is Mach3 doing what it's being told to do. If not there's the problem.

That's how I've always solved problems like these.

Thanks beefy, I agree I like to solve problems that way. I posted a snippet of the g code that it generates in my original post. As the individual I have done my best to try and learn g code while building the machine. I feel I have a decent grasp on it and have tried to diagnose the issue myself. Which led to no results, so that brings me here to seek help on my issue.

The G code looks correct to me, so it might NOT be the post processor..... any suggestions?? G code may be wrong, would you mind checking it for me? Thanks in advance!

[acourtjester]

First I am not trying to be a smartass, You have a problem and have asked for help. Many here help and have different ways of looking at things it does not mean one is better then another. We are remote from you and it is hard to see things on your end, we can only go by what is posted. It may help if you post info about your table, did you buy it or build it. Does it have CandCNC electronics (many here have that for both bought and built table).
The post processor you used will produce a good G-code but is it compatible with your electronics package, if you look in SheetCam you will see there are a great number of post processors. Les has even worked with some for special post processors to fit their needs.
For an example I have used a probe sensor in place of a ohmic sensor, if the post processor is not setup to write the G-code for that there will be a problem with the table but the G-code is still good.
Frustration is a bitch, just hang in there your problem will get fixed and you will have learned many things about CNC and your table.
Remember there is a light at the end of the tunnel, just hope it the exit not the train

[beefy]

The post processor you used will produce a good G-code but is it compatible with your electronics package, if you look in SheetCam you will see there are a great number of post processors.

Acourtjester,

once again, this is taking the "black box" approach to things, i.e. finding a post processor that is compatible with the system. To me the key is KNOWING what gcode commands your particular system uses. Then you can have a quick glance through the gcode which is produced and immediately know if something is not correct.

It not only allows a user to trace a problem in a case like this but it comes in real useful down the track. Chuck a bit of code in here, remove a bit there, it's great. I have a quick scan of nearly every gcode file produced, not all the XY moves of course, just the important little bits (touch off code, M3, M5, Z moves, end of code and parking, etc).

[beefy]

The G code looks correct to me, so it might NOT be the post processor..... any suggestions?? G code may be wrong, would you mind checking it for me? Thanks in advance!

I'm going to send you PM.

[acourtjester]

OZ has spoken!

OZ.jpg

[IndustrialRec]

The G code looks correct to me, so it might NOT be the post processor..... any suggestions?? G code may be wrong, would you mind checking it for me? Thanks in advance!

I'm going to send you PM.

Thanks, beefy.