# What am I missing?

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It's not a very complicated part, but i'm not sure how to draw the angles in the front view on surface C. I know obviously they start .5 down from the top but I don't know how far down towards that cutaway it goes. This is using 2D AutoCAD.

Edited by Jimbo720
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The following should help you to create the cyan colored line in the front view.  Create an auxiliary view from the side view as shown.  Then project back to the front view.

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Thank you for your help! I need to stop always thinking I need to draw front, top, right side then auxiliary. So, when it says for the next auxiliary view to show true angle between surfaces A and C wouldn't a left side view do that?

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A left side view would just show the 60°. You need to construct a view with face A perpendicular to the view angle.

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10 hours ago, Jimbo720 said:

Thank you for your help! I need to stop always thinking I need to draw front, top, right side then auxiliary. So, when it says for the next auxiliary view to show true angle between surfaces A and C wouldn't a left side view do that?

If two infinite flat planes are not parallel their intersection will be a straight line.  To measure the angle between them you would measure it in a plane perpendicular to this line of intersection. Another way to picture the angle is to create a view where you are looking down the line of intersection making the line appear as a dot.   An auxiliary view looking down this line is what you want.  The left view does not provide this.

In my previous post the cyan line lies on both plane A and plane C thus it is collinear with the line of intersection of the two planes.  To determine the angle between these two planes create an auxiliary projected in the direction of the cyan line (up and to the left). It will be a view looking down the cyan line where you can measure the angle between the two planes.  Do you know how to create this auxiliary view?

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Like this?

Edited by Jimbo720
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Yes, very good! Don't forget the hidden edges due to the chamfer and bottom right edge.

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For this drawing do I need to create an auxiliary view to get those angles in the front view? They look parallel but I don't wanna just assume that.

Thanks again!

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The 3 diagonal lines in the front view are due to the edges formed by the oblique plane meeting three different vertical (and parallel) planes.  Therefore the lines are parallel.  You are asked to create a primary and secondary auxiliary view so that you can view the oblique plane in true shape. The primary auxiliary view will be project in the direction of one of the diagonals yielding an edge view of the plane.  A projection off that view will give you the oblique plane in true shape.

BTW, If you are starting a new topic you should start a new thread.

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