STEP 4. Section C

Change the Snap to Grid, then starting at D1, use the Poly Line command to make a line that goes from Dist = .044, Ang =315, then Dist =.406 Ang =270, then Dist =.0702, Ang = 243, and lastly Dist =.063, Ang = 270.  It will look like the highlighted line below.

Use the Mirror X command to mirror the line you drew. When it asks for the Mirror X point, click on the reference line.  Click "yes" when it asks if you would like to mirror while copying.  Next use the Array (Polar) command. The number of copies is 7, and the Angle of Rotation is 45. When prompted to select the entities, select the two lines you just made.  Then right click to complete selecting entities. Click on the center of the circle when prompted for the Center of Rotation to complete the Array (Polar) command.  

Starting at D2 (see below), make a vertical line down that is 0.0625 long, then a horizontal line to the right that is 0.25 long, then goes back up 0.0625.  Then, going from the lower right corner of this box you made, draw a line that is Dist = 0.0884, Ang =135, then from the lower left corner a line that is Dist =.0884, Ang = 45.  It should look like the highlighted section below.

Now use the Array (Polar) command on this box you made. The settings should be the same as before. Click on the center of the circle when prompted for the Center of Rotation.  

Next, use the Arc (Cen, Sa, Ep) command. when prompted for the center, click the center of the circle.  When prompted for the start angle, it should be at the same distance as the outmost circle near the top, and one grid space to the left of the reference line. The end point should be exactly two grid dots to the right of that.  Then delete the circle you made at the beginning of the drawing, so that it now like the figure below.  The arc you just made is highlighted.

Then from the left edge of this arc you just made, make a vertical line down that is 0.0625 long, then a horizontal line to the left that is 0.125 long, and then a vertical line back up that is 0.0625 long.  

Going from D3, use the Arc (Sp, Ep, Mid) command to draw a line that is D=0.6903, Ang = 275.19. The mid point should be Dist =.44, Ang =98.  Then make another arc that goes from the bottom end of the last arc you made to Dist = 0.6875 Ang = 90, and the midpoint is at Dist = 0.25, Ang = 265.  These lines are highlighted below.  Change the line thickness to the widest auto width, and make an arc from the bottom of the last two arcs to Dist = 0.3802, Ang = 279.46 and the midpoint at Dist =0.3187, Ang =101.

Now change the line thickness back to the thinnest auto width.  You will then use the Arc (Sp, Ep, Mid) command and Line command to draw the highlighted lines below.   You will have to change the Snap to None for some lines.

Once again, we are going to have to do some extra work with Arc because the freeware version of CadStd® does not have Trim enabled. Using the Arc (Cen, Sa, Ep), click on the center of the circle, then click D4, which is your start angle.  Finish this arc by clicking four grids to the right of the start angle.  Then delete the circle that this arc overlaps. Repeat this process again, this time the start angle should be one grid space below the last start angle, and the end point one grid space below the last end point.   Delete the overlapped circle.  Repeat this one more time, but the start angle should be D5, and the end point two grid spaces to the right.  Once again delete the overlapped line.  These three arcs are highlighted below.

Now delete the box that is at the top of the three arcs you just made.  Change the line thickness to the widest auto width.  Then use the Line command to draw two vertical lines, as shown by the highlighted lines below.  The left line will  be 0.125 long and the right will be 0.15 long.  Now starting from the top of the left line, draw a horizontal line right that is two grid spaces long.  Then from the end of that line use the Arc (Ep, Sp, Mid) command to draw a line that is Dist = 0.175 Ang =245, with a midpoint at Dist =.099, Ang =45.  Now use Mirror X to mirror all these lines that you just made. when prompted for the Mirror X point, click on the reference line.  Then click Yes to copy while mirroring. 

For the next part, you will have to vary the Snap between Grid, End, and None.  Using the Arc (Sp, Ep, Mid) command, you will draw the four lines highlighted below.  

Finally, set the Snap to Grid, then use the Line and Arc (Sp, Ep, Mid) command to draw the lines below.  You will have to change the line thickness again.  Finally, delete the reference line, and you're finished!

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