How do I draw a torus with a cutout on the inside?

[Torc1]

Please go easy on a newbie!

I've searched for this with no luck. I need to draw a ball bearing outer ring, which would be like a torus with a rectangular profile, with a semicircular cutout on the inside. I tried blending an extruded shape on a circle but got told that extrusions can't be blended. I guess if I flatten the extrusion to a shape it might work, but is there an easier way please?

[Rik]

Depends upon the final result you're looking for?

You can use the Extrude tool to great effect!

Is this the sort of thing you're looking for?

[DOAADI]

The way I've been doing it is to draw two circles, align them centrally, then Combine Shapes >> Subtract. This leaves you with a circle with a hole in the middle.

Then use the 3D tool to extrude it as required.

[Torc1]

Thanks for responding guys. What I need is like the image below, but the circular cutout needs to be on the inside of the ring instead of around the outer circumference.

[PixelDust]

You can extrude an ellipse and use the "Rolled" bevel profile on it.

[angelize]

Hi Torc 1 Welcome to Talkgraphics.

It is indeed possible to do what you are asking and when you mentioned blending extrusions you were close No they can't be blended with the blend tool but there are other ways of blending things!

The first thing is the quickest way to create the ring is to draw an ellipse the approximate size of the hole and give it a heavy out line (the thicker the outline the thicker the ring will be) and no fill(click the crosshatch on the colourline) select the ellipse and go arrange> convert line to shape. You now have a shape you can extrude.

Once you have extruded the ring shape make sure the angles and lighting are correct for your drawing and adjust the bevel for the out side of your bearing outer ring, don't worry about the inner surface yet.

Clone the extrusion (ctrl +K) and with this clone selected now change the bevel to rolled and adjust it for the inner surface of the ring.

With the clone still selected select the eraser tool and set it to a high softness and erase the portions of the clone that you don't want to reveal the original extrusion underneath. by zooming in and out as you work with the eraser you can make the two layers blend quite seamlessly.

[Torc1]

Thank you very much Angelize, just what I needed!

[DOAADI]

Another way of doing it is to use the Combine Shapes function as described, but also use a rectangle to "cut" the circles to leave the flat "half torus" and then apply the 3D tool.

[Torc1]

Thanks again all, here's the final result:

Very grateful for the help.

[angelize]

Looks good Torc, I'm glad you got the help you needed.