[keen]

Hi Folks. All is well in my neck of the woods, just a bit too busy...

Here is a video of setting up the 4th axis and running parts - feel free to post your 4th axis related information.

Cheers Cliff

https://www.youtube.com/watch?v=Bw6VqaHH3uk

[CadRhino]

Nice video, thanks.
Have you ever used the 4th axis homing probe tormach sells. It use to work great with Mach but not so well with path pilot.

Hi Folks. All is well in my neck of the woods, just a bit too busy...

Here is a video of setting up the 4th axis and running parts - feel free to post your 4th axis related information.

Cheers Cliff

https://www.youtube.com/watch?v=Bw6VqaHH3uk

[mountaindew]

Nice video, thanks.
Have you ever used the 4th axis homing probe tormach sells. It use to work great with Mach but not so well with path pilot.

I tried to get the hal sensor to work on my super spacer and path pilot. It seems to work but I think my sprutcam code still unwinds the axis and as mentioned above it takes time.
Need to do a little snooping and hacking now that I read tsteps post.

BTW Keen you make some nice looking parts . I need to add a electronic probe system to my crib. Just looks like a fun tool to use and impress the neighbors.
Adding to this discussion I use a 5c collet holder in my 8" super spacer chuck for small parts. Holds the material away from 8" chuck, very rigid and when I sweep the faces / edges of material or part they align well and easy to adjust. That said a tormach 5c 4th axis holder would be the best solution if its easy to align on face plate.

[keen]

I tried to get the hal sensor to work on my super spacer and path pilot. It seems to work but I think my sprutcam code still unwinds the axis and as mentioned above it takes time.
Need to do a little snooping and hacking now that I read tsteps post.

BTW Keen you make some nice looking parts . I need to add a electronic probe system to my crib. Just looks like a fun tool to use and impress the neighbors.
Adding to this discussion I use a 5c collet holder in my 8" super spacer chuck for small parts. Holds the material away from 8" chuck, very rigid and when I sweep the faces / edges of material or part they align well and easy to adjust. That said a tormach 5c 4th axis holder would be the best solution if its easy to align on face plate.

Thanks - Yes I should get a 5C holder of some type also. Cheers Cliff

[mountaindew]

Thanks - Yes I should get a 5C holder of some type also. Cheers Cliff

Mentioned this because 5c or any collet and holder combo is my favorite part / material / tool holding system. I find I can load material into a 5c / holder and have my way with it on both a 4th axis and a vise on the table at same time. Start with vise and do vertical machine operations then slide into jaws on 4th axis with work stop to repeat and perform all the rotary operations then move back to vise for cut off or other ops. Setup all the offsets one time for first part then repeat for as many as I want make

Side note
In the past looking at pictures of machine shops and walking thru a few. I always wondered why some had hundreds of collets and sets of different sizes. I always figured it was to hold different tools. I understand now I have 2 sets of holders, 2 sets of the same size common collets and drawers full of other sizes and shapes and even a few soft collets like soft jaws

[keen]

"Nice video, thanks.
Have you ever used the 4th axis homing probe tormach sells. It use to work great with Mach but not so well with path pilot."

Thanks - No I do not have a 4th axis home set up - so far I have been able to run the parts before shut down and so have not needed a rotary orientation reset on start up.

I assume that is the main use for it? Cheers Cliff

[CadRhino]

It us useful for me when flipping parts.

"Nice video, thanks.
Have you ever used the 4th axis homing probe tormach sells. It use to work great with Mach but not so well with path pilot."

Thanks - No I do not have a 4th axis home set up - so far I have been able to run the parts before shut down and so have not needed a rotary orientation reset on start up.

I assume that is the main use for it? Cheers Cliff

[IMT]

I have the 4th axis home set up but haven't used it. One of the reasons to use it is so you don't have to "unwind" the axis after a long spiral cut. i.e. if the cut starts at A0 and does 6 revolutions to A2160 then goes back to A0 for the next pass, it will take a minute or so for the A axis to unwind. Re-homing the A-axis after each pass eliminates that.

[keen]

I was wondering if there is a G Code/software script that you can install in the code that will change an axis position - eg on reaching A2160 reset the DRO to A0.00...that would be useful.

Cliff

[TurboStep]

I was wondering if there is a G Code/software script that you can install in the code that will change an axis position - eg on reaching A2160 reset the DRO to A0.00...that would be useful.

Cliff

Hi Cliff
I ran into this issue on my very first 4th axis part. I had to wait 20 minutes for the A axis to return to A0
I solved this in my Sprutcam post but that probably won't help you, but it can be done in G-Code. I just tried this out quickly and it appears to work:

G10 L20 P[#5220] A[#5423-360*ROUND[#5423/360]]
G0 A0

The first line unwraps the A axis by subtracting as many whole turns as necessary to get the machine coordinates within 180 degrees, and the second line should need no explanation.
I suspect someone might have a more elegant equation but I couldn't find many functions that are supported by g-code.
Try it out before you use it to make a part!
Step

[keen]

Hi Cliff
I ran into this issue on my very first 4th axis part. I had to wait 20 minutes for the A axis to return to A0
I solved this in my Sprutcam post but that probably won't help you, but it can be done in G-Code. I just tried this out quickly and it appears to work:

G10 L20 P[#5220] A[#5423-360*ROUND[#5423/360]]
G0 A0

The first line unwraps the A axis by subtracting as many whole turns as necessary to get the machine coordinates within 180 degrees, and the second line should need no explanation.
I suspect someone might have a more elegant equation but I couldn't find many functions that are supported by g-code.
Try it out before you use it to make a part!
Step

Thanks Step ! You know your stuff! I would like to try that. Please would you reply with the exact code for me to enter at the end of my job G code. My code starts on A0 and ends on A270 - but then slowly winds back to A0 at the next run of the code of course. I would like the A270 position to become A0. Would you be able to give me the exact code to insert please.

Cheers Cliff

[spumco]

Cliff,

Assuming you are working the part in G54 offset, then I think the code you append at the end (or beginning) of the run should be:

G10 L2 P1 A0
G0 A0

If you are working the part in G55, then the P-number will be "2"

Taken from Tormach's page on G-code:
To set the coordinate values for the origin of a fixture coordinate system, program:
G10 L2 P~ X~ Y~ Z~ A~, where the P number must evaluate to an integer in the range 1 to 255 – the fixture number (Values 1 to 6 corresponding to G54 to G59) – and all axis words are optional. The coordinates of the origin of the coordinate system specified by the P number are reset to the coordinate values given (in terms of the absolute coordinate system). Only those coordinates for which an axis word is included on the line will be reset.
It is an error if:

• The P number does not evaluate to an integer in the range 0 to 255.

If origin offsets (made by G92 or G92.3) were in effect before G10 is used, they will continue to be in effect afterwards. The coordinate system whose origin is set by a G10 command may be active or inactive at the time the G10 is executed. The values set will not be persistent unless the tool or fixture tables are saved using the buttons on Tables screen.

Emphasis mine on the last sentence. I don't use or know PathPilot, so of course please prove this out in a non-expensive way prior to production work. You could insert that bit of code at the beginning of the program, and it'll be like pressing the A-axis 'zero' button.

Regards,
Spumco

[TurboStep]

G10 L2 P1 A0
G0 A0

If you are working the part in G55, then the P-number will be "2"

The parameter #5220 (see my earlier post) represents the current coordinate system so the following line will be valid irrespective of the coordinate system in use:
G10 L20 P[#5220] A0
Once this has been called PathPilot will believe it's already at A0 so there's no need to call G0 A0 afterwards.
Step

[CadRhino]

You can. just type in 'G0A0' in the DRO and the 4th will return to zero. Thanks


QUOTE=keen;2080600]I was wondering if there is a G Code/software script that you can install in the code that will change an axis position - eg on reaching A2160 reset the DRO to A0.00...that would be useful.

Cliff[/QUOTE]

[keen]

[QUOTE=CadRhino;2080762]You can. just type in 'G0A0' in the DRO and the 4th will return to zero. Thanks

Thanks for posting CR - But if you type in G0A0 it just commands the A axis to mechanically wind to that point? I mean I want a auto 'software position' conversion in the code. Cheers Cliff

[kstrauss]

[QUOTE=keen;2081006]

You can. just type in 'G0A0' in the DRO and the 4th will return to zero. Thanks

Thanks for posting CR - But if you type in G0A0 it just commands the A axis to mechanically wind to that point? I mean I want a auto 'software position' conversion in the code. Cheers Cliff

I suspect that he meant to set the A-axis DRO to zero rather than entering g0a0 in the MDI window. Here g0a0 unwinds while setting A-axis to 0.000 completes instantly. I have not yet tried steps suggestion. Note that the unwind problem is not specific to spurt but occurs with hand coded programs.

[keen]

Hi Spumco - most appreciated. Yes I am in G54. Today I tried G10 L20 P1 A0 at the start of the code and it worked a treat.

I only half understand this stuff - but now I know what to do! The A reset from A270 at program end, to A0 at program start.

Thanks for your input. Cheers Cliff

[handlewanker]

Hi, I'm totally new to any 4th axis moves, so am under some assumptions that may be wrong or right.

I'm also in the process of building a 4th axis so when the day comes I want to have the knowledge to make the correct move etc.

Assuming I'm creating simple hand coded moves and not working with a CAM generated rotation.

The question is........is a 4th axis move the same as an X axis linear move in an absolute mode, but around an object?

Can you have an incremental 4th axis move around an object?

If it is possible to have an incremental degree movement around the work piece where every stopping point becomes A0.....then that would cut out the need to wind back to the A0 starting point each time.......provided you noted how many times and how many degrees you moved in each move if you wanted to wind back to the original A0 beginning.

EG, from A0 if you moved 30 deg in a CW direction and then 20 degrees more this would mean you are now 50 deg from your starting point but at a new A0 point when you stopped and every time you stopped after that.

Also, what would the move be to rotate back ACW from any A0 position........incrementially speaking?
Ian.

[IMT]

Does PP require line numbers? I'm still using Mach3 and it doesn't care if there is line number or not, and the Sprutcam post only outputs line numbers to 4 digits and starts over again so they are of no value to me.

[TurboStep]

Does PP require line numbers? I'm still using Mach3 and it doesn't care if there is line number or not, and the Sprutcam post only outputs line numbers to 4 digits and starts over again so they are of no value to me.

Good point! I'd always thought that either you had line numbers or you didn't, but if you had them they had to be correct. I don't know where I got that from but it's apparently untrue - at least for PathPilot. I just tested lines mixed with and without numbers and counting up and down in the same code. The code looks horrible but PathPilot doesn't appear to care.
I'd actually prefer to turn them off altogether because I've never needed them either - how to do that in Sprut?
Thanks for the pointer...
Step