Newbie question: all axes *home* forwards yet *jog* backwards?

OK, so perhaps a variation of this will get the right direction. I may try to do some dry run tests with the plasma off, perhaps doing lettering so I could tell if it is backwards.

Re: "Jog + must move the machine to the right and away from you, so that seems wrong."

I should add that while it is physically left and toward me (instead of right and away), on the screen in QTPlasmaC, it is indeed right and away. Does that help?

Re: "all motion on X and Y must be positive, for Z must be negative."

In my DRO, my Z movements are in positive range instead of negative.

In my DRO, all my X and Y movements are in positive numbers.

It seems like I may be OK on X and Y but still need attention on Z.

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My convoluted story of getting SUCCESS on Z:
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So, every time I tried to use the normally advised approach, I would wind up with no travel distance. On some rare occasion in a myriad of explored options I would wind up with travel distance but headed the wrong way, and probing headed up towards end stop switches instead of down toward the material.

So sorry to be such a newbie with such a lack of understanding.

Regarding the following, I have no doubt that I have come at this backwards because of lack of understanding, but (again) I was unable to get the range of motion to work when attempting the methods that are normally advised. 

To get homing success on Z, I finally resorted to the following:

I split my 5.2" travel height in two, with machine zero origin at 2.6" below the homing switches, with 2.6" positive movement above  the center point, and 2.6" negative movement below the center point, and then I had to tell the homing direction to go toward  negative, and then edit the INI file to delete the minus sign in front of the stepper scale amount on both Z joints, 3 and 4. I think this was also with check marks on the "invert" option for both Z main step gen and Z2 tandem step gen, in the PNCconf setup wizard (still not sure what that does). 

Somehow this gets the movement for probing in the right direction, and probing works!

I know there can be advice given for how to come at this the right way, but since this is working and I am loathe to break it!

Now to get the probing heights and pierce and cutting heights set in Parameters.

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I also now want to mount sight-line red lasers to my torch mount, for aligning X and Y before cuts!
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Quick question about stepper direction and homing setup:

Are these three changes all equivalent, meaning they all accomplish the same end result?

• In the PNCconf setup wizard, select the "invert" checkbox option for step gen
• In the INI file, add or remove "minus" from the STEP_SCALE value
• In the machine's wiring, flip the stepper wiring  

OK thanks.

Re. inverting in PNCconf, there are three options:

Invert on TB3, where homing is done with INM inputs, and invert on TB1/TB2 for Step Gen-A, or Dir Gen-B.

I was check marking Step Gen-A, and did not seem to be getting any perceivable result. 

I got a reply from a friend that it should have been on Dir Gen-B.

Does that sound right?

And if so, what does invert of Step Gen-A do?

This is an area where I still have confusion.

I finally have a fully working, perfectly orienting homing setup and motion control system. It could probably be tweaked to avoid having to manually edit the INI file to remove minuses from the STEP_SCALE values!

Thanks again for being so awesome!

UPDATE: I did indeed get my setup tweaked so no manual edits were needed to the INI file. 

tommylight wrote:

Start over.
The way you have it now makes it impossible to use as everything in CAM must be set to negative values.
Start over, get jogging right, then homing. The wizard makes it very easy, for homing choose towards negative limit for X amd Y, towards positive limit for Z.
Also, all motion on X amd Y must be positive, for Z must be nagative.
There are cases that above can be different, but not in your case.

Somehow for me in the end, success came from using the opposite homing approach -> for X and Y I had to choose "towards positive" and for Z I had to choose "towards negative." And the end result also is that all my X and Y motions are positive, and my Z is negative on approach to the material for probing / float Z switch. I'm also accomplishing all this by use of PNCconf only, with no manual edits to the INI file.

I'm not sure how it is that my homing directions needed to be the other way, but I'm glad to say that the motion is correctly oriented for my table, which I had earlier sadly and incorrectly conceded as seemed undoable. I think my struggle was so great because for the longest time I questioned every setting except which way to home toward, because the advice on that was so clear.

Below is a quick video showing the homing and a dry run on cycling through a cut. I have more to do but I'm thrilled with this milestone.

My hat is off to all of you that have helped so wonderfully, especially Tommylight, in this thread. Thank you for being so awesome!

Got a successful first cut test!

forum.linuxcnc.org/49-basic-configuratio...-i-m-beyond-excited/

Also getting great info from the awesome responses over there!