Photoshop Bobbers
Discussion
Turtle Shed said:
Or anyone with half a brain who can work out that 0,0,0 is the origin in three dimensions.
G28 tells the machine to park itself on the machine zero position not the G54 datum position as set by the programmer or setter.
Depending on the type of CNC control and how the machine is configured to the control one of the last lines of code you will see in a program for a standard 3 axis vertical mill will be
G28G0Z0Y0
This tells the machine to rapid traverse (G0) from it's current position to the machine zero position (G28) ignoring any preset G54 datums but only in the Z (vertical) and Y (front to back) axis. So the head would move up and park itself in line with the tool changer and move the bed as far forwards as possible.
If you programmed
G0Z0Y0
Then you would probably have a collision as the G54 datums would still be active and all sorts of carnage would result.
The use of X0 in conjunction with a G28 depends on the machine, if I programmed G0Z0X0Y0 at the end of a program on one of our HAAS CNC's any operator would call me a
and rightly so as the machine zero point is to the right and the operator wouldn't be able to reach the vice. If I didn't include the X0 on our Fanuc Robodrill they would be equally pissed off as the machine datum is to the left...This is the much simplified version ignoring G55/6/7/8/9 and also G10 datum set commands used in conjunction with G90 & G91
Tango13 said:
Turtle Shed said:
Or anyone with half a brain who can work out that 0,0,0 is the origin in three dimensions.
G28 tells the machine to park itself on the machine zero position not the G54 datum position as set by the programmer or setter.
Depending on the type of CNC control and how the machine is configured to the control one of the last lines of code you will see in a program for a standard 3 axis vertical mill will be
G28G0Z0Y0
This tells the machine to rapid traverse (G0) from it's current position to the machine zero position (G28) ignoring any preset G54 datums but only in the Z (vertical) and Y (front to back) axis. So the head would move up and park itself in line with the tool changer and move the bed as far forwards as possible.
If you programmed
G0Z0Y0
Then you would probably have a collision as the G54 datums would still be active and all sorts of carnage would result.
The use of X0 in conjunction with a G28 depends on the machine, if I programmed G0Z0X0Y0 at the end of a program on one of our HAAS CNC's any operator would call me a
and rightly so as the machine zero point is to the right and the operator wouldn't be able to reach the vice. If I didn't include the X0 on our Fanuc Robodrill they would be equally pissed off as the machine datum is to the left...This is the much simplified version ignoring G55/6/7/8/9 and also G10 datum set commands used in conjunction with G90 & G91
Is the correct answer!!!
..... and here's Bobbers demonstrating how it's done!
Although he hasn't learnt it yet, so still needs his crib sheet.
bob_cnc by conradsphotos, on Flickr
Although he hasn't learnt it yet, so still needs his crib sheet.
bob_cnc by conradsphotos, on FlickrC n C said:
..... and here's Bobbers demonstrating how it's done!
Although he hasn't learnt it yet, so still needs his crib sheet.
bob_cnc by conradsphotos, on Flickr
User name checks out Although he hasn't learnt it yet, so still needs his crib sheet.
bob_cnc by conradsphotos, on Flickr
:C n C said:
..... and here's Bobbers demonstrating how it's done!
Although he hasn't learnt it yet, so still needs his crib sheet.
bob_cnc by conradsphotos, on Flickr
Well it looks cooked to meAlthough he hasn't learnt it yet, so still needs his crib sheet.
bob_cnc by conradsphotos, on Flickr
lancslad58 said:
Bobbers, DO NOTPRESS THAT BUTTON ! It could take us anywhere, do you want to be stuck in NP and E forever.
Distracted by a copy of What Lathe? magazine, he played a part in Spurs' inexplicable rise up the table before Chelsea and others complained
Edited by CourtAgain on Tuesday 21st November 19:34
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