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View Full Version : Using an Ogee Bit aroud a Profile


jim_vv
06-07-2008, 07:44 PM
Greetings. I have been commissioned to make a retirement plaque for a marine. I am going to cut out the plaque (the shape of the chevron patch)with a profile pass. I planned on cutting the double ogee on my router table but I will have to make a spacer to lay over the front as the front of the plaque has a raised relief on it. I use ArtCam Pro and noticed an Ogee tool in the tool database. It would be really nice if I can have my ShopBot follow around the profile with my double ogee cutter. Here is my question: I want to edit the properties of the default cutter. What dimensions do I put in for the Relative Offset? Do I check the Relative to inner (d) box?
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beacon14
06-07-2008, 08:51 PM
Not sure about ArtCam but to do what I think you are asking I just measure the distance from the center of the bit to the edge of the workpiece and create an offset line that distance from the perimeter of the workpiece. Then profile on that offset line.

Sometimes drawing the profile helps to visualize the results.

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myxpykalix
06-07-2008, 10:46 PM
David,
It looks like you are measuring to the shaft diameter. Wouldn't you measure to the outside diameter of the cutter since the shaft is probably always going to be the same (1/4" or 1/2") but the diameter of the cutter could be bigger sizes?
beacon14
06-08-2008, 12:39 PM
Jack, each profile is different, but the critical dimension is the distance from the center of the bit to the edge of the material - that is the distance to offset from the edge of the workpiece to get to the center of the toolpath.

The bit in the previous example happens to have a profile that begins at the shank diameter - common for bits with ball bearings. Not all bits are like that though. That's why I like to draw the profile and the workpiece edge. You could measure the bit diameter and subtract the amount that the bit cuts into the workpiece to end up with the same critical measurement.

BTW depth of cut can be critical as well. Here's a chamfer I just drew at random; using the offset and depth shown should give the results as drawn.

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