The JonRocket.com Centering Ring / Motor Mount Tool generates custom, printable centering ring templates for internal body tubes and motor mounts.

Paper Size: Select Letter, Legal, A3, A4, or A5 based on the size of the paper in your printer.

Main Body Tube: Select the main (outer) body tube that you are using or "Other" to manually enter the diameter.

Main Body Tube Diameter: If you selected "Other" for the Main Body Tube, then enter the diameter of the body tube. Be sure to select the proper units in the "Units" field.

Body Tube Units: Select the units for the manually entered body tube diameter ("inches," "millimeters," or "centimeters").

Center Body Tube: Select the center body or motor tube that you are using or "Other" to manually enter the diameter.

Center Tube Diameter: If you selected "Other" for the Center Body/Motor Tube, then enter the diameter of the tube. Be sure to select the proper units in the "Units" field. Select 'None' for no center tube.

Center Tube Units: Select the units for the manually entered center tube diameter ("inches," "millimeters," or "centimeters").

Outer Tubes Offset Diameter: Enter the diameter of a circle which where the centers of the outer tubes will be placed. In other words, enter twice the distance that the center of each outer tube will be from the center of the main body tube.

Outer Tubes Offset Units: Select the units for the outer tubes offset tube diameter ("inches," "millimeters," or "centimeters").

After you click the Submit button, the template will be downloaded as a PDF file. When printing the template, make sure to select the "Actual Size" setting. The outer square in the lower right should be one-inch wide and one-inch high. The inner square should be 20mm high and 20mm wide.