Help- optimizing Moulding Tool paths

[zombolina]

Hi there,
So I learned how to use the moulding toopath today. I have these long curved shapes cut do out of 1.5” MDF in the profile shown. Screen grabs are from the test length.

The Profile sweep clearing path goes only where I want it, down the side of the bevel. But as you can see, the finishing path goes over the whole part, so 60% of the time it is cutting air.

How can I get it to just go over the bevel?

Thanks for any help!

[dealguy11]

Can't really help without seeing the vectors. The clearing path only cuts the areas that need to be cleared, so it's not unexpected that it would only cut in that area. Post a file with the vectors so we can see what's going on with the finishing path.

[zombolina]

Been trying to post a response with a photo of the vectors all evening and I get met with a blank screen... see if this works

[zombolina]

Ah, here it is. As you can see I used the outside curve for the rail and swept it with the profile below it. The clearing path was right where I wanted it, but the finishing path comes over the top surface of the part. Not cutting, just taking s long time cutting air

[dealguy11]

It looks to me like your sweep vector actually goes over the top, so the toolpath is doing exactly what would be expected. If you were to actually cut this, the vertical plunge at the left end of the profile would probably be fatal to a thin carving bit.

Unlike the 2-rail sweep, it is not necessary for the sweep vector to return to the bottom of the profile when you're doing a moulding toolpath. Your sweep vector should look more like the following picture. Note the tiny legs at the top and bottom that force the bit to cover the entire profile. The one at the top is probably optional in this case, but I always put it in. The one at the bottom is important to make sure the bit goes all the way to the bottom. Its length needs to be at least the radius of the bit. You will also need to offset (i.e., re-draw) your rail by this amount.