2D Part Lesson 1 - BobCAD-CAM

2D Part Lesson 1
For this lesson we are going to take a look at the steps to create the following drawing using
the tools inside of the BobCAD-CAM software.
First we must decide how we are going to approach this drawing. The main features of this
part are the outside profile shape of the part, the two drill holes, and the three interior pockets
of the part.
Drawing the Outer Profile
• Begin by starting a new drawing inside of the software by clicking the File Menu and
selecting New.
• It is always good practice to separate your major part features into different layers. So
we will create a new layer for this drawing and name it PROFILE. Use the following
steps to create the PROFILE layer:
◦ First make sure the layer tab is selected in the Layer-UCS-Post Manager and right
click anywhere inside the window.
◦ Next select Add Layer and a new layer will be added to the layer list.

◦ Type in the name for your new layer and name it PROFILE. (Note: If the cursor is
not all ready flashing in the name field for the layer, the user can click+pause+click
the text in order to edit the name.)
◦ Click on the PROFILE layer icon so that a check mark appears, making it the active
layer.
• Begin the outer profile by drawing the 3 main arcs that comprise the outside shape.
Parts of these arcs will also be used for the internal pockets later on in the lesson.
◦ Select the Arc Menu and select Arc Coordinates.
▪ Enter 2 in the Radius field
▪ Set the Center X, Center Y, and Center Z fields to 0.0000
▪ Enter 0.0000 in the Start Angle.
▪ Enter 360.000 in the End Angle to draw a complete circle.
▪ Click OK to create the arc in the workspace

▪ Change the Center X to -4.0
▪ Change the Radius to 0.5
▪ Click the OK button to create the next arc in the workspace
▪ Change the Center X to 4.0
▪ Click the OK button to create the next arc in the workspace
• Next we want to add in the four tangent lines that connect these three arcs to finish the
outside shape.
◦ Select the Line Menu and select Tangent
◦ Click the arcs in the following locations in the order shown below to create the 4
tangent lines.

Drawing the Internal Pockets
• Before beginning drawing the interior pockets of the part, start by creating a new layer,
naming the layer POCKETS, and making this the active layer. The steps for creating a
layer can be found in the prior section Drawing the Outside Profile.
• Next we need to finish completing the internal pockets of the part. To do this we first
need to add the linear edges of the pockets
◦ Select the Line Menu and select Parallel
▪
▪
Enter 0.25 in the Distance field because we can see in the above print that the
pocket boundary is 0.25” away from the outside profile.
Click the top left line in the workspace and then move the cursor towards the
inside of the part and click again to place the parallel line.

▪
Repeat the last step for the last 3 lines that make up the outside profile, placing
the lines to the inside of the part. The result should look as follows:
• Next we will need to break some of the entities at their intersections in the workspace
in order to complete the necessary fillets.
◦ Select the Utilities Menu and click Break and select Many
▪
Click and drag a window around all of the entities in the workspace.
▪
Next click the 4 lines we made in the previous step so that they are not selected
because we do not need to break these entities, and by not breaking them we
will avoid having to delete a lot of extra entities later on.
▪
Complete the break function by right clicking in the workspace and selecting
OK.

◦ Select the Arc Menu and select Fillet
▪
▪
Enter 0.125 in the Radius field
Click the entities shown below in the order shown to complete the necessary
fillets to complete the inside pockets.
• Finally we can add the large circular pocket at the center of the part.
◦ Start by clicking the Arc Menu and selecting Arc Snap.
▪
▪
Enter 1.5 for the Radius
Leave the Start Angle and End Angle at 0.000 and 360.000 respectively.
◦ Next while holding the Shift key down on your keyboard select the arc at the top of
the part. This will activate the snap points allowing the user to select the arc center.
Click the center snap point located at the origin to create the new arc. The result
should look as follows:

Drawing the Drill Holes
• Before beginning drawing the outside profile of the part, start by creating a new layer,
naming the layer HOLES, and making this the active layer. The steps for creating a
layer can be found in the prior section Drawing the Outer Profile.
• As we see in the print, this part requires two 0.25” diameter holes at each edge of the
part.
◦ Start by clicking the Arc Menu and selecting Arc Snap if the function is not all
ready active.
▪
▪
Enter 0.125 for the Radius
Leave the Start Angle and End Angle at 0.000 and 360.000 respectively.
◦ Next while holding the Shift key down on your keyboard select the arc at the far left
of the part. This will activate the snap points allowing the user to select the arc
center. Click the center snap point located at arc center to create the new arc. The
result should look as follows:
◦ Repeat the last step, selecting the arc at the far right to place the final hole
You have completed 2D Part Lesson 1!