Sketching on New Plane

geoff_josey

I have a rectangular block with two holes thro the block. The original rectangle was on the top plane.
I now want to create 2 cut outs centered on each hole. When viewed from the bottom I create a new sketch, but when drawing lines to the outside of the block (rectangle as in original sketch which was used for the extrusion) There does not seem to be a line to meet. When you extrude is the new edge not created ?
Sensor Mount X Axis   
https://cad.onshape.com/documents?resourceType=filter&nodeId=1

MBartlett21

Can you share a link to when the document is open?
It should be something like
https://cad.onshape.com/documents/12312312345abcabcabcdeff/w/a855e4161c814f2e9ab3698a/e/459d631d67c38b8d80944f2f

geoff_josey

Sorry I am not clear on what you are requesting. Are you saying the link and title in the original post are not OK ? Its a public document.

MBartlett21

See https://forum.onshape.com/discussion/9107/forum-post-checklist

geoff_josey

I have opened the doc. and this is the link
https://cad.onshape.com/documents/2258500c16af1bee0560d432/w/12daed955e3e0f47b42530c4/e/3d8d18f298622
Are you saying that I am not conforming to the guidelines ? I have read them via your link.
Thanks

dick_van_der_vaart

@geoff_josey
I made a copy of your document
https://cad.onshape.com/documents/9fc1dee378020e00e5a7b953/w/7bee8c770d7290726f44dcdb/e/9e69fee1751735ee949b478f
Is this what your trying to do??
If you are looking for something else, here's a link to some starting video's,
https://www.onshape.com/videos/topic/intro-to-cad

Good luck

geoff_josey

Apologies for the delayed response. Thanks for your help. Yes- that is exactly what i was trying to do. Looking at your example I managed to achieve the result. I have been trying to understand where I went wrong. I notice you did not trim the circle where it impinges on the rectangle. I seem to have a problem when I have a very simple sketch with a rectangle which has circles at the edge of the the rectangle ie as per cuts out. The circles also have tangential lines going to the edge of the rectangle The trim function deletes the full line or circle. I think I am missing something basic, but have watched the videos and searched the discussions without sucess
Thanks

dick_van_der_vaart

@geoff_josey
I have made another copy of your file,
https://cad.onshape.com/documents/3612e1c4f71f206ec324fee8/w/8829098b3990e98ab121eeb3/e/aa60c821159e15824ecee184
In Part Studio 2 you can see a different aproach, only model half if your part is symetric, that save's time.
The first sketch is fully constraint, that,s a good practice.
In the second sketch you select the contourlines and the hole, and use the üse command.
For using the tangent command, first select the straight line and then the circle.
After finishing the extrude, mirror the part and select add, not new.
Good luck