Help with design - 2 halves of a cylinder

[katiecoloney]

Hi all! I have no experience with CAD outside of the Carbide 3D training videos and what I have learned through trial and error, so I am hoping you can help me with what I thought would be a simple design

I am trying to make a tool handle by carving 2 halves of a sort of cylinder that I can epoxy together. Please ignore the red/flat spots on top of the pieces - I am using MDF as test material that is half as thick as the wood I will use for the final product. I cannot figure out how to get the round component correct to make the sides round. Can someone please help me understand why I am getting this result where there is about 1/4 inch on the sides that is flat? Any suggestions for better designing principles?

I really struggle to learn from videos, so if anyone has any resources for texts to help me learn basic 3d designing principles, I would be super grateful for those recos!

[WillAdams (William Adams (Carbide 3D))]

The red indicates that the model extends beyond the extent of the stock.

Use thicker stock and increase the height in Job Setup, or model the design to be lower.

There are a couple of 3D tutorials at:

Tutorials

and also see:

3D Modeling from 2D Geometry | Design into 3D

[Randy (Randy Gordon-Gilmore)]

@katiecoloney, the 3D toolpath is not taking the cutter centerline past the part outline. and to finish to the part edge the .250 diameter cutter would need to go .125" past the part outline (i.e. all the way out to where the contour toolpath is).

I don’t have the Pro version of CC, but in MeshCAM I can set the margin of how far outside the part outline the toolpaths extend. Sorry. Someone (likely @WillAdams ) will help you with that.

[katiecoloney]

Hi Will, that’s clear and I am using thinner stock as test material. My question is about the flat sides (circled in the photo of the finished result) and how to model something with round sides all the way down to the bottom of the stock.

[Randy (Randy Gordon-Gilmore)]

@katiecoloney , see this thread which is exactly the same geometry situation.

[katiecoloney]

Hi @Randy thanks for your response! If I redraw the shape with an offset to account for the tool diameter, that will cause the 3d toolpath to cut all the way down to the bottom of the stock? Will I also need to adjust the contour toolpath to avoid the flat sides?

[katiecoloney]

Thank you this is helpful, and also helped to pre-emptively solve a problem that I wouldn’t have anticipated (the tabs)

[Tod1d (Tod (with 1 'd'))]

As mentioned, the tool tip (center of tool) is stopping above your boundary, which is likely the edge of the 3D shape. Offset by the radius of the tool to allow the tool to completely cut the shape.
Note it will still stop at the bottom of stock & leave a radius, so you’ll want to add a base and increase the stock thickness by the radius of the tool. Also note that now it will cut the radius of the tool below the part, and into the spoilboard so using a secondary dispensable spoilboard is advised.

[katiecoloney]

Thank you so much, this is graphic is super helpful!!