Some basic tips required

nyholku

I've been using Onshape quite a lot. And like it a lot. Most things work like charm.

Couple of things elude me:

1) If sketch part with a hole in it and extrude it, how can I extrude that hole to create a 'pin' that fits the hole?

To me this looks like it should be trivially simple but I always end up creating a new plane on the extruded surface, sketch, use that hole in that sketch and extrude the sketch ... there must be a simpler way.

2) I often start a part as a symmetrical rectangle, again this seems to require more steps that I would like:

I sketch the rectangle and then vertical and horizontal symmetry lines from the origin and then make the rectangle symmetric both vertically and horizontally.

A lot steps to just create a rectangle to start actual design...

Jake_Rosenfeld

@nyholku

1) You can extrude the part with the hole, then un-hide the sketch and do another extrude of just the pin (by selecting the circular region as the region to extrude by clicking in the graphics area).  Make sure the second extrude is set to "New" and not "Add".  If you want the two extrudes to be the same height, you can either use a variable ( https://cad.onshape.com/help/Content/variable.htm ) or the second one can be an up-to-face extrude.

2) Try using a center point rectangle:
https://cad.onshape.com/help/Content/sketch-tools-rectangle_center.htm

bradley_sauln

Hey @nyholku have you had a chance to take a look at some of our courses in the learning center? These can help you a lot with starting scenarios like this.

For the first question, you can create a second extrude feature and select the hole from the first sketch you created (it may be hidden so you will have to show the sketch again) and then choose to extrude as a "NEW" solid. It will probably default to add since the pin is touching the first part you made.

For the second, using a center point rectangle has these constraints already applied for the most part, to achieve the symmetry you desire: https://cad.onshape.com/help/Content/sketch-tools-rectangle_center.htm?tocpath=Desktop%20Help%7CPart%20Studios%7CSketch%20Tools%7C_____3

nyholku

Thanks guys, I knew I was going to feel pretty silly I had totally missed the center point rectangle tool, I believe it was not there in the early version and somehow my brain failed to see that that little down pointing menu 'arrow'.

As to the extruding just the hole I should have been more specific. If I preselect the edge that defines the hole and click sketch then it defaults to surface and if I then change that parameter to solid the system clears the selection (silly, but not a big deal). But very often I have then trouble selecting the hole while the parameter box is open: try as I might very often when I move the cursor around no matter where the whole sketch gets selected, not only the hole. Is there a 'trick' how succeed every time?

MBartlett21

@nyholku

For (1) you can extrude a part as "New"
Boolean subtract it from the other part with keep tools checked

owen_sparks

nyholku said:

As to the extruding just the hole I should have been more specific. If I preselect the edge that defines the hole and click sketch then it defaults to surface and if I then change that parameter to solid the system clears the selection (silly, but not a big deal). But very often I have then trouble selecting the hole while the parameter box is open: try as I might very often when I move the cursor around no matter where the whole sketch gets selected, not only the hole. Is there a 'trick' how succeed every time?

Here you need to be selecting the enclosed sketch region not the edge of the hole in the part.  Chances are your sketch will be hidden so you'll need to "show" it by clicking on the eye icon in the feature tree next to the sketch in question, or if your model isn't too cluttered by right clicking in the viewing area and selecting "show all sketches".

Personally I find OS's default behavior of automatically hiding sketches it thinks you're done with annoying.  The is an IR here should you be of similar mind.

Cheers,

Owen S.

Jake_Rosenfeld

@nyholku

If you post a link to an example document we may be able to help.  It sort of sounds like you may be adding an additional sketch overlapping your initial sketch, which shouldn't be required.

billy2

@nyholku

one thing to note about OS that's not true in SW. OS can handle face references when dimensioning or mirroring. When mirroring, turn the planes on and use them. No need to draw vertical or horzontal lines. Face references in a sketch are a true blessing and a real short coming in SW.

As far as using 1 sketch to drive many features, I do it all the time. In fact sketches are now my mini-layouts for subsequent features and I name them so I can identify what's going on in the feature tree.