This is a customizable, parametric 3D design for a \”truly touchless\” no-touch tool, designed to allow opening doors, pushing buttons etc. without coming into direct physical contact with the surfaces. The tool is \”truly touchless\” in the sense that the tool itself, which potentially could be contaminated with material from the surfaces it touches, is hidden in a sleeve and protected from accidental touches by the user.

Usage

Use the tool to open doors, push buttons or pick-up objects without touching them with your hand. Extend the tool by pushing the knob with your fingers. See a video of the basic functionality here: https://youtu.be/b8Q2DCqatQQ

You can lock the tool in its extended state by moving the knob sideways into the diagonal slot.

In daily use, you can attch the tool to your pants, belt or pocket using a lanyard or an extensible \”badge yo-yo\”. The end cap has a slot for attaching it.

The tool should offer the user some protection against accidental touch infection by means of its design. However, users may want to disinfect it. For disinfection, the tool blade can be rinsed in alcohol or any sterilizing liquid, or wiped off with a suitable substance, depending on your context. If you want to be able to sterilize the tool, make sure to

print it with a material that quite literally can take the heat. Common materials like PLA and PETG are not heat-resistant enough.

Customization

The model is almost totally parametric, so you can change everything – make it taller or wider, change some functionality, use different means of attachment, generate different quality – by changing variables in the SCAD file.

In the default configuration, the model generates an STL file with all the parts for a tool that is about 9.5 by 3.5 by 1 cm, held together by M3 bolts.

For a more extended overview of common customization use cases see the master README on Github.

For a detailed overview of all possible customization options, you can also see the source code, the options are documented. You can customize pretty much everything – dimensions and functionality.

FAQ

I have customized the model and now need separate STLs for the parts.

Go to the beginning of the SCAD file and set the GENERATE_BODY, GENERATE_SLEEVE, GENERATE_ENDCAP and GENERATE_BOLTS to generate only those parts that you need.

Rendering in OpenSCAD is really slow!

That is true. The main culprit here is that most edges in the model are chamfered. This looks and feels nice in the printed object, but it generates lots and lots of little polygons around every edge that take long to render.

Another culprit is the \”roundness\” of the rounded parts – in OpenSCAD

this is the $fn setting.

For the same reason, this model probably won’t work very well in the online customization in Thingiverse Customizer: large numbers of small polygons.

Compiling the design in OpenSCAD gives an error message about aborting normalization! (Also: I get assertion errors in OpenSCAD!)

Same as above. The model is a bit taxing on OpenSCAD\’s rendering. When making changes to the model, best set CHAMFER and ROUND_CIRCLES to false for the time being. That should reduce the complexity enough to work in a normal OpenSCAD compilation workflow. Then set them back to true when exporting STLs. (In an earlier version of the model, these variables were called WORK_IN_PROGRESS.)

In spite of whatever messages you see during compilation and rendering, the model should render fine (F6 in OpenSCAD). I tested it using OpenSCAD 19.01 (in Ubuntu) and 19.05 and it works on both.

To do

The tool currently cannot be used well with capacitive touchscreens. This is because they react to the electrical conductivity of your finger, and the printed material has different electrical properties. You could try to print it in a conductive material, or integrate some wires into the tip. Older (resistive) touchscreens do work somewhat better.

Source repository and attribution

The master GitHub repository for this model is https://github.com/phrxmd/touchlesstool. Licensed under Creative Commons ShareAlike-Attribution 4.0 International.

The original idea comes from a non-parametric Fusion 360 design by Elwin Alvarado published here. Used with permission. This version here was rewritten in OpenSCAD for easier customization and has an extended set of features – notably attachments for a rubber band, tool locking, printable bolts and others.

Version history

• v0.1: Initial design based on SCAD adaptation of Elwin Alavarado\’s original idea. Added rubber band fixture v1: vertical slot, ring around bolthole
• v0.2: Added bolt to model; rubber band fixture v2: round hooks on front and back (slips too easily)
• v0.3: Added lanyard slot to endcap; rubber band fixture v3: hooks on the left and right (too strong)
• v0.4: Horizontal locking slot; screw-through bolt design; rubber band fixture v4: open space with rubber band posts
• v0.5: Diagonal locking slot for easier printing; added screw hole to endcap
• v1.0: First published version
• v1.1: Added keyring hole to endcap, based on this idea from Matt Bordoni; fixed a few bugs
• v1.2: Added debugging for parts placement below XY-plane