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The videos above shows how to draw a piston assembly in Freecad/Croquet. Follow the steps below for the complete guide.

• Click File>New>CAD Project. A new CAD Project frame will be added into the world at the ground position in front of the avatar. You will see the X, Y and Z axes representing the origin of the frame. You can also view the CAD Project you have added in the tree view menu on the left.

• Click File>New>Assembly. A new assembly frame will be added into the CAD Project frame.

• Click Insert>Part>New to add a part frame into the assembly frame.

• Click Insert>Sketch to insert a sketch frame into the part frame.

• Click Draw>Rectangle to start drawing a rectangle. The lightly tinted sketch frame on the X-Z plane will be visible at this point.

• Move the mouse over the sketch plane and you will see a pop-up showing the position of the mouse cursor.

• Adjust to the position you want the rectangle to be placed at then click and drag the mouse to extend the drawing. We will roughly draw the rectangle on the sketch board and adjust its properties later.

• Middle-click or use Alt+Left-Click on the rectangle to show the pop-up menu.

• Select ‘Position’ on the pop-up menu. A window will pop-up showing the attributes of the rectangle.

• Change the values to:-

X Position = 1
Y Position = 1
Z Position = 0
Angle        = 0
X Length   = 1
Y Length   = 0.2

• Remember to hit the ‘Enter’ or ‘Tab’ key on the keyboard after changing the values.

• Click the ‘OK’ button on the window when done. The changes on the rectangle will take effect immediately.

• You can adjust the camera’s view to see the drawing better, to do this, use the ‘W’, ‘A’, ‘S’, ‘D’ keys on the keyboard to move the camera forward, left, back and right. you can also tilt and rotate the camera by holding the ‘Shift’ key plus any of the ‘W’, ‘A’, ‘S’, ‘D’ keys. The up and down arrow keys will move the camera upwards and downwards.

• Click Insert>Feature>Extrusion to extrude the rectangle. In the Extrusion window, enter the values:-

zStart = -0.1
zEnd  =   0

• Remember to hit the ‘Enter’ or ‘Tab’ key on the keyboard after changing the values.

• Click the ‘OK’ button on the window when done. The changes on the rectangle will take effect immediately.

• Our first rectangle is done. To draw another rectangle click Insert>Sketch to insert another sketch into the part frame.

• Click Draw>Rectangle and roughly draw another rectangle on the sketch board.

• Middle-click or use Alt+Left-Click on the rectangle to show the pop-up menu.

• Select ‘Position’ on the pop-up menu. A window will pop-up showing the attributes of the rectangle.

• Change the values to:-

X Position = 2
Y Position = 1
Z Position = 0
Angle        = 0
X Length   = 1.5
Y Length   = 0.2

• Click Insert>Feature>Extrusion to extrude the rectangle.

• In the Extrusion window, enter the values:-

zStart = 0
zEnd  = 0.1

• The above values will create a solid positioned right above the first rectangle.

• Remember to hit the ‘Enter’ or ‘Tab’ key on the keyboard after changing the values.

• Click the ‘OK’ button on the window when done. The changes on the rectangle will take effect immediately.

• You can rotate the solid around the X, Y or Z axis using the Rotate window.

• To bring up the Rotate window, middle-click or use Alt+Left-Click on the rectangle to show the pop-up menu.

• Select ‘Rotate’ on the pop-up menu. The Rotate window has 3 scroll bars to adjust the rotation around the X, Y and Z axis respectively.

• Click and drag the scroll bar for Z Rotation to 110, use the left and right arrow buttons on the scroll bar to get the exact value.

• Click the ‘Close’ button when done.

• Next, we will draw a cylinder as the piston’s head. Click Insert>Sketch to insert another sketch frame.

• Click Draw>Circle

• Roughly draw a circle on the sketch plane by clicking and dragging on the plane.

• Middle-click or use Alt+Left-Click on the circle to show the pop-up menu.

• Select ‘Position’ on the pop-up menu. A window will pop-up showing the attributes of the circle.

• Change the values to:-

X Position = 1.5
Y Position = 2.5
Z Position = 0
Angle        = 0
Radius      = 0.5

• Click Insert>Feature>Extrusion to extrude the circle.

• In the Extrusion window, enter the values:-

zStart = 0
zEnd  =  1

• Middle-click or use Alt+Left-Click on the circle to show the pop-up menu.

• Select ‘Rotate’ on the pop-up menu.

• Click and drag the scroll bar for X Rotation to 270, use the left and right arrow buttons on the scroll bar to get the exact value.

• To move the solids around, click on it and drag. The pop-up shows the position of the solids. Align the piston head to the 2nd rectangle.

• The piston assembly is now complete.