I didn't have a cutoff operation selected. I was finally able this morning to get the operation "perfect" using the tips from above. Thanks a lot everyone for your input - I guess I will call customer support before they release a new version and then say "Of course your having that problem - you haven't upgraded to the latest version!" Thanks!

Well, those are some more interesting instances. I have tried to do the tabbing last, but still being partially human, I usually can't get it right still. So, I am still wondering why the chains are duplicated and missing. I rarely let Mastercam choose where to put the tabs. Since some of my parts are specific to have a finished edge along one side, I can't have Mastercam decide where to put the tabs. I always choose myself. Can you move a tab after it's already been inserted? How? The 3D tab idea is a thought.

I am working with Mastercam X4 and have been having this problem with X3 and X2 as well. I am doing very simple 2D programming, just lines with contour tool paths, tool compensation, at programmed depths. The recurring problem I am having comes when I try to alter a tool path after creating it to leave tabs so my small parts will hold down. After I regen, the tabs are either gone, or half of them have changed from partial to full tabs (X4 only). The other irritating part is that after I do adjust the geometry or tool path, some of my 2D chains will not show on the screen. When I look at the chain list under the tool path, the chains are still there, but many of my chains will be duplicated and many will be gone. The only way I have found to fix this is to delete the operation, and start a new one. BUT - I have to do it perfectly the first time, otherwise the chains will be duplicated, some will disappear and my tabs will be wrong. Any help would be great, as this has become a daily problem.

So, if you're not at the office, do you know where you are? On the file I have open right now, it seems that the tabs are sticking, and I do have the TAB ALL selected under tab settings. Let me try this with a few other files, and I let you know if this fixes it. Thanks!

Do you mean under the automatic tab setting? I don't use automatic tabs, I manually enter them.

Hello-does anyone have any help for me-what do you mean by chek your stock?

Has anyone ever had a problem with disappearing tabs in a contour toolpath? I have set them in X2 and X3 and once I set them, and run verify, they are there. However, if I edit that toolpath in any way, (add a chain, change the settings) the tabs disappear. When I try to go back in and add them, I click on the chain and it says they are still there, but they are not outputting when I post or verify at that point. The only way I've found to get them back is to delete the contour and completely re-toolpath it. What a time waster! I am not doing a cutoff operation. Any Ideas?