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Beginner needs help...

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I have been trying to draw this but am struggling and having a hard time visualizing it. Do I need to make a side view to complete the front and top view?


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Note that the part is symmetric except for the 12 DIA hole and the triangular notch in the front and the long notch in the back.


I would  start in the top view and draw a horizontal line 51 long in x, then 49 long at an angle of 50° (my two red lines). Create two more lines like these that are their mirror (my green lines),  Close this 2D shape and extrude it by 22 in z.   Make a couple of large boxes (100 x 100 will do) that are 11 high. Position these boxes as necessary so that you can do a Boolean subtract to make the two cutouts on the under side (I've circled in blue).


The tilted piece on the left side can be constructed in place but it may be easier to construct it in a vertical or horizontal plane and the rotate and move it to the correct position for doing a Boolean union. I hope this helps you get started.


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I think I misread the problem and assumed you were trying to create a 3D model of the object.  It looks like it is an exercise in creating 2D views from other 2D views using the descriptive geometry methods that were created for manual drafting more than a 100 years ago. I'm sure there is some value in doing this in 2018 but  I think your time would be better served learning how to build 3D models and making 2d views from them.


Enough with my pontificating and back to your front view construction challenge.


Your top view is wrong because the auxiliary view from which the rounded portion is created is wrong.  The 49 dimension should be 43.  You should create the full auxiliary view before finishing the top view.  I've added some projection lines to show you how things line up.



I made a copy of your auxiliary view (before I noticed the incorrect dimension) and positioned it to the right of the front view and then created some projection lines to the front view. We can determine some critical points and slopes for the half ellipse that is needed for the front view by projecting lines from the top view and my copy of the auxiliary view. In the pencil and paper days we would fudge in an ellipse using an ellipse template from these points and slopes.   The easiest way I know to create the magenta ellipse with AutoCAD is to create a head-on view of the shape and then rotate it in 3D. The white shape in the upper left of the drawing is that head on view.  I then used rotate3d to rotate the shape first by -35° (90-55) about the x axis and then +40° about the y axis.  This resulted in the cyan colored shape to the right of it.  Flatten was used to project the result onto the XY plane resulting in the magenta colored shape.  Flatten made an ellipse of the arc that was no longer parallel to the xy plane.  It was then I discovered the 49 vs. 43 error.


I suggest you fix the error in the auxiliar and secondary auxiliary views then us the rotate3d method for creating the ellipse as AutoCAD doesn't feature a method for creating an ellipse using 3 points and 2 slopes.  Better yet, create a 3D model of the shape and view it from any angle you desire!


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