Are lathe offset values on radius or diameter?

[sinha_nsit]

Are the offset distances on a lathe always radial values even if we are using diameter programming?
In other words, if we increase the wear offset by 0.01, will the machined diameter increase by 0.01 or 0.02?

[Karl_T]

On my lathe its radius and negative. make offset more negative by .0005 to increase diameter by .001. I got a note on the machine to not screw up.

Karl

[Boots]

To be sure of what you have just run a teast part and measure it against what you programmed.

[g-codeguy]

When I first started working on lathes, they were programmed in radius and the offsets were in radius. All our lathes are now programmed in diameter, and all offsets are in diameter.

[sti2011]

It would seem to me that if you program in dia. the offsets should be the same. I think the machine can be set to either depending on your preference. Although dia. should allow finer resolution. As .0001" rad. is .0002" dia.. We had a Robodrill installed that was set to rad. for tool dia offsets.....Silly giving up the finer resolution. A simple parameter change later and better parts
As before mentioned a test part will tell you what you are dealing with. And if it is rad. I would call your dealer or the man. and find the parameter to change to dia.

[sinha_nsit]

You are right.
I checked on 0i Mate TC (I started this thread because I wanted to save my time!). My machine (rear-type lathe) uses diameter programming. So, all offset distances are diameter values.
Moreover, when I specify a negative wear offset (which was initially 0), it pulls the tool towards the spindle axis by the specified amount, without changing the coordinate display. This means that a smaller diameter would be obtained for the same program. So, to compensate for tool wear (which gives larger OD than the programmed value), a negative wear offset value should be specified, in case of OD machining on a rear-type lathe.
Am I right?