Tool offsets in Dolphin
Posted by
John Stevenson
on 2001-10-02 10:31:40 UTC
I have put two screen shots of the way Dolphin handles tool offsets
on my web site at
http://homepage.ntlworld.com/machines/offset1.jpg
http://homepage.ntlworld.com/machines/offset2.jpg
This text file is also there at
http://homepage.ntlworld.com/machines/offset.txt
The screen shots just show on a very simple file how easy it is to use tool
offsets or if you prefer, not to use them.
Some programs at present like CNC Pro from Yeager can't handle G41/G42 tool
offsets so you have to draw the offset path and process that.
Dolphin allows you to chose from a menu how you want to do this.
The screen shots both show the same part, in this case a simple 2" square
is to be machined with an 0.5" diameter tool. I have chosen these sizes as
they generate easily understood numbers.
If you look at offset1.jpg you will see the black square with the 0,0 zero
point at bottom left. The blue square is the tool path. This has been
generated by the program adding the tool radius to the square. If you look
at the code you will see in lines 160, 180, 200, and 220 that the allowance
has been made. This is fine is all you want is a shape with no firm
tolerance or your controller can't handle tool offsets.
If however you need to control the part size using tool offsets then take a
look at offset2.jpg
By just selecting "Use part surface" in the options check box you can see
that the black square and the blue tool path are one and the same. In lines
150 to 180 you have the exact 2" square defined but at the start of line
140 the tool offset is called up.
In both cases just the simple 2" square had to be drawn or imported as a
dxf file. The approach and depart points are automatically generated from
the Approach/Runoff option.
The same post processor file is used the only thing that has changed is the
check box on the part surface command. Any of these commands can be called
up again and edited, there is no need to touch the original drawing. If you
decide to use a 3/8" tool then edit the tool and repost the file and the
code will take the new tool into account.
Thank you for you time.
John Stevenson
---
Regards
John Stevenson
Nottingham, England
on my web site at
http://homepage.ntlworld.com/machines/offset1.jpg
http://homepage.ntlworld.com/machines/offset2.jpg
This text file is also there at
http://homepage.ntlworld.com/machines/offset.txt
The screen shots just show on a very simple file how easy it is to use tool
offsets or if you prefer, not to use them.
Some programs at present like CNC Pro from Yeager can't handle G41/G42 tool
offsets so you have to draw the offset path and process that.
Dolphin allows you to chose from a menu how you want to do this.
The screen shots both show the same part, in this case a simple 2" square
is to be machined with an 0.5" diameter tool. I have chosen these sizes as
they generate easily understood numbers.
If you look at offset1.jpg you will see the black square with the 0,0 zero
point at bottom left. The blue square is the tool path. This has been
generated by the program adding the tool radius to the square. If you look
at the code you will see in lines 160, 180, 200, and 220 that the allowance
has been made. This is fine is all you want is a shape with no firm
tolerance or your controller can't handle tool offsets.
If however you need to control the part size using tool offsets then take a
look at offset2.jpg
By just selecting "Use part surface" in the options check box you can see
that the black square and the blue tool path are one and the same. In lines
150 to 180 you have the exact 2" square defined but at the start of line
140 the tool offset is called up.
In both cases just the simple 2" square had to be drawn or imported as a
dxf file. The approach and depart points are automatically generated from
the Approach/Runoff option.
The same post processor file is used the only thing that has changed is the
check box on the part surface command. Any of these commands can be called
up again and edited, there is no need to touch the original drawing. If you
decide to use a 3/8" tool then edit the tool and repost the file and the
code will take the new tool into account.
Thank you for you time.
John Stevenson
---
Regards
John Stevenson
Nottingham, England