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I was wondering how everyone else incorporates 'overburn' when programming electrodes. I have been taught to 'lie' about tool size in order to get negative offsets in XY direction, but not in Z.

I have tried to figure out a parameter to automatically change my tool size by a known amout (overburn), but parameters do not work in the tool setup dialog box.

You can specify negative stock allowance, but when changing for rough to finish electrode programs, there are many places to change (each NC sequence), and the chance for mistakes seems greatly increased when using this method.

Just wondering what everyone else does.



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Create and offset surface (the amount of rouger or finisher), use this to do create, cut, use quilt, to reduce your electrode size. Then make a family table to control amount of offset, create an instance for rougher and an instance for finisher. Then program one instance (eg rougher). To change to finisher, just replace rougher instance with finisher instance and regen.


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The problem with that method is that our geometry is almost always complex shapes, and the overburn only needs to go in the XY direction, so I don't think that offset surface will work.


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Yes complex shapes are an issue the offset method, but if it works half the time, then use it half the time. It doesn't take long to find out.

In actuality, if you are using a spherical orbit, you do need offset in X,Y, and Z.

Consider a spherical electrode: if you only applied OB in X and Y it would no longer be spherical, no orbit (square, circular, or spherical) would return it to its correct shape

When you alter your tool diameter, this is the same as offseting in X,Y, and Z.

If you want to shift back up so that you have a common Z touch for rougher and finisher, create and offset coordinate system for you MFG to reference.

Our MITS seeker don't require this, however. We touch of with a finisher, load roughers and finishers, and it handles the offsets.


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This is what I do tell me if you see a problem.. In the NC Sequence under Parameters there is an seting called PROF_STOCK_ALLOW I enter a - number for my overburn.

ie -0.01


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