Sizing a domed dish for smooth transition

[TomWS]

I am trying to make a carved round top for a box using the Magnolia & Domed Dish Clipart. I wanted an 1/8" bead around the dish and thought the Moulding Toolpath would be the proper way to do this.
However, if I use the same dimension for both the size of the domed dish and the circle vector used for the drive rail on the moulding toolpath, then the preview shows a bit of an edge between the bead and the dish rather than the smooth transition I expected.

Preview with edge shown with red arrow.

If I make the dish a bit larger than the drive rail (3.53" vs 3.50") then it appears that the two are blended together better.

Is this normal or am I going about this in the wrong way? I tried to attach the crv file but it's too big. I am using a 1/8" dia tapered Ball Nose for the 3D Finish and an 1/8" Ball Nose for the Moulding.

Bead Profile

[adze_cnc]

How is a tapered bit going to make the vertical walls of the bead profile?

[TomWS]

How is a tapered bit going to make the vertical walls of the bead profile?

It isn't. The moulding toolpath uses a 1/8" Ball nose, not tapered ball nose. The 3D Carving uses a tapered ballnose. FWIW, I did try the straight 1/8" ball nose for the 3D toolpath, but it had no visual affect to the observed edge.

[adze_cnc]

Ah. Sorry. Mostly looked at the image only. My thought is that with the shape of the moulding profile provide the ball end bit will stop once it goes past vertical. This will leave a bit of material behind. Hence the ridge left over.

If you could create the profile of this dish you could combine a portion of it with your moulding profile to allow the ball end bit could trace the two to blend between the dish and the bead.

[TomWS]

I wish I could attach the .crv file. The bead profile actually has a 0.030 straight extension on the half round. I was hoping that would make the moulding toolpath cut lower than the tangent to the bead. But, as I type this, I seem to recall that any vertical end to the moulding profile is ignored which, back to your point, may be my problem.

I either need another toolpath to get the ball end tool to cut deeper or, as I discovered, make the dish slightly larger diameter - or... maybe I'm doing this all wrong!

I wonder if I raise the dish slightly, maybe make it slightly taller to compensate (so the bottom is at the same level), then the top edge of the dish will intersect the bead profile on the vertical???

[TomWS]

If you could create the profile of this dish you could combine a portion of it with your moulding profile to allow the ball end bit could trace the two to blend between the dish and the bead.

I think I just got what you are saying (maybe not, but the interpretation is interesting). Rather than using the dish clipart to make the dish, make a moulding profile that not only includes the bead, but the side wall and rounded bottom of the curve. Then have that blend into the flat surrounding the magnolia. I probably have this wrong, but it does sound promising. It would certainly remove any issue with blending the edge between the two.

[Rcnewcomb]

If the file is too large to upload here you can use a file sharing site such as drive.google.com, onedrive.com, or dropbox.com. They all have free accounts available

• Upload the file to the file sharing site
• Make the link shareable
• Share the link to the file here

[TomWS]

The technique of using the Moulding Toolpath to create the dish as well as the bead worked like a champ! Thanks to @adze_cnc for his advice!