The device you are going to print should be precisely scaled to the recipient for maximum convenience and usability.

To do this scaling, you need to know the width of the recipient’s wrist on their disabled hand. If you can easily meet him you can measure on him directly, otherwise you will use the photo of his hands placed palm flat on the table.

Go to this site and load the picture.

Click on two known points on the ruler (for example 10cm and 20cm).

The software displays a line between the two points, and a fancy measurement. Double click on the measured value and enter the correct value in mm (100 in our example).

All of the following measurements will be displayed correctly using this scale.

To find out the width of the disabled wrist at the joint, click on each side at the line that represents the joint. Add 5mm to the measured value for comfort.

To find the scaling coefficient, multiply this value by 2.55.

For example, a 40mm wide wrist will need a device printed at (40 + 5) * 2.55, or 114%.

The coefficient of 2.55 is valid for the Raptor, Raptor Reloaded and Phoenix hands.

Before printing, check that the palm printed after the coefficient is applied is not too different in size from the recipient’s valid palm.

For those of you who are familiar with Blender, Peter Binkley has created and shared

this vidéo, thanks Peter.