How to sketch atop multiple faces?

josh_mccullough080

See here: https://cad.onshape.com/documents/7a95e4e5ecc3df14bfe96b68/w/dcc38852fdcd046c79f14ab9/e/f219ea2cea573f2e9dd4e463?renderMode=0&uiState=63f53b0cc392ad69d1d0b795

Note that I have a sketch created from the top face of the circle extrusion. Within that sketch I've drawn the areas shown by the green arrows but I can only extrude the portion of the sketch which is drawn on the circle's face. Also, I cannot trim the back portion of the circle (pink arrow).

Do I have to make 3 separate sketches, one on the circle and then one on each rectangle? I thought I was able to tackle this with one sketch. Thanks.

steve_shubin

@josh_mccullough080

Different areas of your sketch were not ENCLOSED

You can tell if something is enclosed because there will be a gray shading to show what area is enclosed in a sketch.

I used the USE tool to enclose them. You could’ve also used the line tool at the cuboid projections and the arc tool on the cylinder

steve_shubin

@josh_mccullough080

Different areas of your sketch were not ENCLOSED

You can tell if something is enclosed because there will be a gray shading to show what area is enclosed in a sketch.

I used the USE tool to enclose them. You could’ve also used the line tool at the cuboid projections and the arc tool on the cylinder

josh_mccullough080

Thank you, that helps! It also explains why sometimes my sketches have extra stuff from the face I'm sketching on.