Lathe usage post processor.

[Delco]

Looking for a post processor to use the lathe with fusion .
I choose the mach3 one BUT it seems to output the diameter values not the radius values so my part is twice the diameter that its modelled in .
Is there a setting in uccnc to change from radius mode to diameter mode ??

[dezsoe]

If you use 1.2116 or 1.2117 then check for G7/G8 to switch between diameter/radius mode.

[Delco]

But what post processor has been used for testing by cncdrive for fusion ? , I have tried a heap of fusion posts and they all post in dia but uccnc works in radius.

In mach3 you could switch between radius or dia mode - cant find anything similar in uccnc ?

Any documentation on lathe for uccnc yet ???

[dezsoe]

In 1.2116 or later you can use G7 for diameter and G8 for radius mode.

Sorry, now I see your problem: the user manual for 1.2116 does not mention G7 and G8. Please, download 1.2117, the manual in it contains the descriptions:

Lathe Diameter Mode: G7
Program G7 to enter the diameter mode for axis X on a lathe. In lathe diameter mode the X axis
moves will be 1/2 the distance to the center of the lathe. For example X1 would move the cutter to
0.500 Units from the center of the lathe thus giving a 1 Unit diameter part.

Lathe Radius Mode: G8
Program G8 to enter the radius mode for axis X on a lathe. When in lathe radius mode the X axis
moves on a lathe will be the distance from the center. For example X1 would result in a part that is
2 Units in diameter. G8 is default on the software startup.

As far as I know none of us uses Fusion, so I can't tell you anything about its postprocessors.

[Delco]

So to be clear , all that is required is to have a G7 in the intilization string and then the dro will read diameter rather than the radius , and a normal post processor that outputs dia can then be used.

All the post processors for fanuc, haas , mach3, mach4 that I have seen output the gcode as a diameter.

Would it be possible to have a setting that could be set to dia or radius in the setup ? for the next version

[cncdrive]

Yes, we could make a setting like that, but I think it is easier if you setup the post processor for your CAM program to put in G7 or G8 in the beginning of the g-code file.

[dezsoe]

I agree with Delco: the setting is important for all lathe users. As important as the default plane selection was, because lathe users hardly never use the lathe in radius mode.

[Delco]

Or how do we get it to default to Diameter mode on startup , 99% of the post processors out there seem to use diameter mode ?