Filament type: PETG

Layer height: 0.20mm

Infill: 15-20%

Supports: Yes

Wall count: 5

Estimated filament used: 58 Grams

Print difficulty: Easy

Print time: About 2 Hours 15 Minutes

Added materials:

• M5 X 18 Bolt

• M5 Nut

Tools needed:

• Screwdriver or Allen key, depending on bolt

• Pliers for support removal

Post processing: Support Removal

Time to assemble: 5 Minutes

Assembly Process: Place the device onto the doorknob, place the nut into the cutout on the device, insert the bolt through the hole, and secure the lever to the doorknob with a screwdriver or Allen key.

Functional Use: This device is a clamp-on adapter that fits over a round doorknob and adds a lever arm, allowing a person to push the lever down instead of gripping and twisting the knob. It can be scaled to the size of the knob.

Relevant Occupations: Functional Mobility

Client Factors: May be relevant when grip strength or forearm range of motion is reduced.

Performance Skills: The lever turns a rotating grip into a downward push, so the client presses the lever rather than gripping and turning the knob.

Safety Considerations: The clamp can slip on a smooth knob, so add a thin strip of Dycem around the knob if the grip is loose, since a slipping adapter on a door creates a fall risk. Measure the knob first so the printed fit is right.

Limitations: The device size is set when printed, so an incorrectly measured doorknob means reprinting. It is not a cleared medical device, so its use must be a clinical decision made by the treating occupational therapist.

Issues: None

Recommendations: This device can be scaled to fit different sized doorknobs. The original model is sized for a 54.9 mm (2.16 in) diameter doorknob.

To scale this device, use the following formula:

1. [User doorknob size in mm / 59] × 99 = scale percentage

2. For example, if the doorknob is 47 mm, the calculation would be:

3. (47 / 59) × 99 = 78.07

4. In this case, the device should be scaled uniformly in the slicer to 78.07%.

Note: The nut and bolt size will change when the model is scaled.

Ease of use: Easy

Test results or review: The part works as intended.

Original file link: https://www.thingiverse.com/thing:2729961

Creator credit: Rcolyer

License: Creative Commons - Public Domain Dedication