material zero reference

Share tips and tricks regarding cut cutting, material handling, metal finishing, marketing, or anything helpful.
Post Reply
MS76
Posts: 20
Joined: Sun May 27, 2018 7:59 am

material zero reference

Post by MS76 » Wed Sep 11, 2019 10:09 am

For those of you that have installed a UPS backup on your tables computer, how do you record your starting point or material reference if you need to restart a cut after an electric outage?

robertspark
Elite Contributing Member
Elite Contributing Member
Posts: 375
Joined: Mon Jun 12, 2017 6:43 pm
Location: nr Liverpool, UK

Re: material zero reference

Post by robertspark » Wed Sep 11, 2019 10:54 am

Home your machine before you start.

Record your machine co-ordinates at the start of a cut operation to a log file.
(depending upon what cnc software you are running you could create a macro to log the machine co-ordinates when the macro is called). So if using sheetcam, just insert a macro as part of the post processor to be called at the start of the job "OnInit()" or "Operation".

You can then use G53 to jog to the machine co-ordinates location once the machine is rehomed and start from that location. (this could be automated from a macro to reopen the log file and call the last co-ordinates via a button on screen)
UCCNC,
Sheetcam
Hypertherm Powermax 45 (nonXP)
Neuron Lite THC
Hobby user (4x4 home table)

robertspark
Elite Contributing Member
Elite Contributing Member
Posts: 375
Joined: Mon Jun 12, 2017 6:43 pm
Location: nr Liverpool, UK

Re: material zero reference

Post by robertspark » Wed Sep 11, 2019 10:58 am

Its probably a bit more helpful if you list / explain your setup (i.e. Mach3 / Linuxcnc / uccnc / sheetcam / fusion360 etc etc) as someone may have what you want in macros to automate the process for you
UCCNC,
Sheetcam
Hypertherm Powermax 45 (nonXP)
Neuron Lite THC
Hobby user (4x4 home table)

MS76
Posts: 20
Joined: Sun May 27, 2018 7:59 am

Re: material zero reference

Post by MS76 » Wed Sep 11, 2019 1:24 pm

Thanks for the responses. I have written down my coordinates at the start but am not in the habit of it. I am running sheetcam, command cnc linux on an arclight dynamics table. I frequently use inkscape on my drawings

MS76
Posts: 20
Joined: Sun May 27, 2018 7:59 am

Re: material zero reference

Post by MS76 » Wed Sep 11, 2019 1:27 pm

I'll have to look into that on sheetcam roberspark, that sounds interesting.

robertspark
Elite Contributing Member
Elite Contributing Member
Posts: 375
Joined: Mon Jun 12, 2017 6:43 pm
Location: nr Liverpool, UK

Re: material zero reference

Post by robertspark » Wed Sep 11, 2019 1:32 pm

I can help with sheetcam (that's easy)...
I have not written macros under linuxcnc so cannot help there (I keep trying to dabble with linuxcnc with a Mesa + thcad card but I've got too many other projects that are work in progress.... plus if you have a working setup that you are happy with why change....)
UCCNC,
Sheetcam
Hypertherm Powermax 45 (nonXP)
Neuron Lite THC
Hobby user (4x4 home table)

Rodw
Posts: 263
Joined: Sun Aug 21, 2016 1:49 am

Re: material zero reference

Post by Rodw » Wed Sep 11, 2019 5:36 pm

On Linuxcnc, you could log every probe event very simply with comments at the beginning and end of every job. You might be able to use the file gcode name as the basis of the log file within the sheetcam post.
(LOGOPEN,probe-results.ngc)
; cut here
(LOGCLOSE)


See http://linuxcnc.org/docs/html/gcode/g-c ... #gcode:g38
and an example file mentioned above:
https://github.com/LinuxCNC/linuxcnc/bl ... tprobe.ngc

robertspark
Elite Contributing Member
Elite Contributing Member
Posts: 375
Joined: Mon Jun 12, 2017 6:43 pm
Location: nr Liverpool, UK

Re: material zero reference

Post by robertspark » Wed Sep 11, 2019 6:37 pm

Rod,

its not after probing that the OP wants to log the current machine co-ordinates, however, thanks very much for the info as I think I may have the right direction below.

it looks like you could do the following:

Code: Select all

G30.1 (stores the current absolute position into parameters 5181-5186)
(LOGAPPEND,startcoordinates.txt)
(----)
G53 G0 X#5181
G53 G0 Y#5182
G53 G0 Z#5183
(LOGCLOSE)
I would suggest placing the above code in an *.ngc file and running it and seeing if it saves your current machine co-ordinates for you. where I placed the (---) this will act as a marker so that you know that the last co-ordinates will be at the end of the file. I added the G53 G0xxxx so that cou could just copy and paste them into the MDI and the machine will move to those co-ordinates. It should not move the machine when the co-ordinates are logged, given the machine won't move anywhere given that is where it is located as the G30.1 is given just before the (LOGAPPEND)

The LOGAPPEND was used so that you have one file with all the info added to it so the last info is the most current (i.e. if you have a power outage that is the place to go to for a restart).
UCCNC,
Sheetcam
Hypertherm Powermax 45 (nonXP)
Neuron Lite THC
Hobby user (4x4 home table)

Rodw
Posts: 263
Joined: Sun Aug 21, 2016 1:49 am

Re: material zero reference

Post by Rodw » Wed Sep 11, 2019 7:55 pm

@Robert, My thinking was if you logged the probing event, you would get a log of the coordinates on every pierce. But yes the logappend is also a good solution

MS76
Posts: 20
Joined: Sun May 27, 2018 7:59 am

Re: material zero reference

Post by MS76 » Wed Sep 11, 2019 10:36 pm

Thank you both for your responses! So many members on here amaze me with their knowledge and willingness to help those of us that have so much to learn. As it would have it by coincidence, I've had a 7 hour power outage today although I wasn't running my table only my powder coat oven at the time.

robertspark
Elite Contributing Member
Elite Contributing Member
Posts: 375
Joined: Mon Jun 12, 2017 6:43 pm
Location: nr Liverpool, UK

Re: material zero reference

Post by robertspark » Thu Sep 12, 2019 3:03 am

maybe the probe event is better on second thoughts it will just log every pierce point


I guess it's some options to play with

where on the planet are you ?
UCCNC,
Sheetcam
Hypertherm Powermax 45 (nonXP)
Neuron Lite THC
Hobby user (4x4 home table)

MS76
Posts: 20
Joined: Sun May 27, 2018 7:59 am

Re: material zero reference

Post by MS76 » Thu Sep 12, 2019 7:04 am

I'm from north east Ohio robertspark

beefy
Posts: 1372
Joined: Fri Jan 18, 2013 3:19 am

Re: material zero reference

Post by beefy » Fri Sep 13, 2019 6:30 pm

MS76 wrote:
Wed Sep 11, 2019 1:24 pm
I have written down my coordinates at the start but am not in the habit of it.
Well, I can only make one suggestion to that comment.........get in the habit. You can't get back if you don't know exactly where you were.

I always plan for the worst when I cut. First I home the machine, then XY machine co-ordinates should automatically be set to zero (normally) at the home position. Note though that some software may give the option to have the home position at something different from zero, for example if you had your home switches at the lower right corner of your table the home position could be X2500, Y0. Then the software would automatically set the machine co-ordinates to these values when homing is done.

Next I jog to the lower left corner of my sheet and I take a photo with my smart phone of the X and Y postion DROs while I'm still in MACHINE co-ordinates. Now change to WORK co-ordinates and zero the XY DROs.

I can now start cutting. If my machine shut down in the middle of a cut, then once the machine is running again:
Home it.
Ensure I'm running in MACHINE co-ordinates (I find it quicker to click the machine/work co-ordinate button that to type "G53")
Use MDI (manual data input) to jog to the machine co-ordinates where my plate XY WORK zero position is (the smart phone picture I took).
Change to WORK co-ordinates
Zero X and Y DROs
I am now back at the exact X0, Y0 position for my cut.

Keith
8 x 5 water table
Powermax 1250 with Duramax torch
UCCNC controller, UC400-ETH & UC300-ETH motion controllers.
Sheetcam
Geomagic Design 3D solid modelling
Coreldraw X5

Thor
Elite Contributing Member
Elite Contributing Member
Posts: 142
Joined: Wed Jun 17, 2015 6:57 pm

Re: material zero reference

Post by Thor » Fri Sep 13, 2019 7:24 pm

If you have Command CNC you dont need to write it down. I home my machine and then use fixture offsets to auto locate the corner of a sheet off some machined blocks that fit my table sides. I use G55 for cold rolled sheets and G56 for hot roll (I think its like .075" farther inward then G55 is).

Even if you dont use fixture offsets Command Cnc remembers where you zeroed last, given that your machine has homing switches.

Thats one thing they did great on Command Cnc is its tracking of machine zero and work zero (G54) and the use of Fixture offsets. If I have to modify a part I move to a good spot on a sheet of steel pushed into the corner of the table, then cut an outline that the part fits into. And record that same Zero posistion into a new Fixture offset, and make sure the program calls it up in the beginning before any movement. Then I can still come back to it months later, provided I keep track of which Fixture offset I was using and dont need it for something else (In which case a quick camera pic of the offset page and throw the pic in the appropriate file. Much the same as I do on my CNC turning and machining centers. If I know its going to be a long term job I'll write the fixture offset numbers into some human readable notes at the beginning of the program along with any other setup info needed.

beefy
Posts: 1372
Joined: Fri Jan 18, 2013 3:19 am

Re: material zero reference

Post by beefy » Fri Sep 13, 2019 9:55 pm

Hi Thor,

I use UCCNC and have an "Offset" page with G54-G59, so can save six work zero offsets to disk.

The reason I take a photo (or write down) the work zero machine co-ordinates, it that I don't like leaving anything to chance.

In the past I've had PCs die on me in the middle of a cut, or when I come back to the PC the next day and want to continue a cut but the PC is dead. I think being in a tin shed is not good for PCs LOL, probably due to condensation, plasma dust, etc. If my PC and my smartphone with the photo die at the same time, then I guess I'm just doomed.

Keith.
8 x 5 water table
Powermax 1250 with Duramax torch
UCCNC controller, UC400-ETH & UC300-ETH motion controllers.
Sheetcam
Geomagic Design 3D solid modelling
Coreldraw X5

Rodw
Posts: 263
Joined: Sun Aug 21, 2016 1:49 am

Re: material zero reference

Post by Rodw » Fri Sep 13, 2019 9:58 pm

beefy wrote:
Fri Sep 13, 2019 9:55 pm
If my PC and my smartphone with the photo die at the same time, then I guess I'm just doomed.

Keith.
Nah, if you use Google Android your photo will be backed up to the cloud in Google photos before it dies. :Yay

beefy
Posts: 1372
Joined: Fri Jan 18, 2013 3:19 am

Re: material zero reference

Post by beefy » Fri Sep 13, 2019 10:11 pm

Hey Rod,

what I meant though, was that I wouldn't go buying a lottery ticket.
8 x 5 water table
Powermax 1250 with Duramax torch
UCCNC controller, UC400-ETH & UC300-ETH motion controllers.
Sheetcam
Geomagic Design 3D solid modelling
Coreldraw X5

Post Reply

Return to “Tech Tips”

Easyscriber engrave attachment for Hypertherm plasma cutters.