Is your IJ mode set to absolute? It ran fine on my PC ( simulation mode) with IJ set to incremental. Also, only your first G42 has a D1. Every G42 needs a D1, and you also need the tool diameter for tool1 set in the tool table.

His program has a G91.1 in it, also D1 is global as far as I know.

Graham.

Ok here is something else to add to the mix..When I run it without a tool being selected...TOOL 0...it runs just fine ,no problem except there is no offset..When I put in TOOL 1...that is when it goes off...Graham ,this is what was throwing me for a loop on that wing rib that you helped me on..It finally worked properly with the tool offset when I put in a P.0625 at each and every G41 down the list..Putting in the TOOL1 is what is messing this up

ger21...I checked the IJ mode..yes it is set to absolute ...I have the tool diameter set at .125

Graham..what is the G91.1 and how is it getting in there,if it not suppose to be there?

I don't get it, it works fine here.

Tool 1 offset are set to :-

dia = .125
length =0
wear dia = 0
wear len =0

Here is the mach path and the code I used to do it.

Michael,
     What version are you using?

Graham,
    What version does it do good on for you?

I am running R1.84.00...When I simulate the run,that is the only thing I am changing..The Tool 1 ..or...Tool 0..I created a new modified code by inserting the P.0625 at each G41..I am going to try that now..Will let you know..Graham..when you ran my original tap file,did you put in a TOOL ..?or was it set to TOOL 0      ..?  also when you rewrote the code, you took out the drill points..which is fine,because I don"t think that has anything to do with it..And on my original tap,the drill points and the holes ran fine until it got out on to the outside profile..which is weird because it will start just fine on the profile, maybe a third of the way and then off it goes..and when it goes off,it is where there is  a straight line and then it hits a curved line..Right where the two lines meet..But the profile was drawn in Autocad using a closed polyline,so there is no gap there..Michael

Well..It didn't work with the G41 all having P.0625...Tool 0...It did the crazy course again...Here is the screen shot and the modified tap file with all G41 P.0625 ...in it..If you are able to make my file run on your machine,then I must have some bug in mine..What gets me is I have two computers running this with the same results..Computer one is the one inside that I design on and one outside in the shop where the mill is...same results...I must have some bug or something...

His program has a G91.1 in it, also D1 is global as far as I know.

Graham.

Graham, the D1 didn't appear to be gloabal for me. Only the first circle was comped.

Michael, I think there are some comp (G41/G42) bugs in 1.84. Try it with the latest version.

Graham, I just checked and the D1 is not modal for me. Try this. Use .25 for the diameter of tool 1.

Apologies Gerry, you appear to be right, that is a major problem and needs to be corrected.

The repercussions of it are huge. For one it meens that any form of subroutine using external D command are out.

I think this needs pointing out to Art and Brian.

Graham.