Introduction: Hands-Free Wall-Mounted Hand Sanitizer Dispenser
We have a stock of hand sanitizer inside the front entrance of our home thanks to COVID-19, but a hands-free one outside is ideal as it allows sanitizing before coming in contact with the house. So we built a simple wall-mounted one that can be built from string and wood scraps or 3D printed. It works perfectly and has proved very handy for our family which includes a middle school science teacher and two students entering Grade 10 & 12 this Fall.
Step 1: Design and 3D Print
The idea is simple: provide a means of depressing the plunger of a hand sanitizer dispenser with your foot. By attaching it to the wall, no support structure is needed. This design (made with Fusion360) has a mount for the hand sanitizer and a pedal. They're connected with some strong string. Print both parts below (I used an Ender 3). I designed this one for a snug fit for a bottle we owned - a 320 ml/11 fl oz short round bottle. But it can be scaled in the slicer to accommodate whatever similar bottle you own, or you can play with the designs yourself through these links: wall mount, pedal.
Both parts can be printed at the same time with no support necessary. The combined print (wall mount and pedal) uses 108 g of filament and takes a little under 14 hrs at an infill density of 20% and a layer height of 0.2 mm.
Step 2: Assemble
Drill two holes (larger than the string diameter) through either side of the plunger. Get some strong string and thread it through those holes. Pass each end down through the tubes either side of the mount, and through the outside holes in the pedal. Tie knots under the pedal to secure the string. Drive screws through the holes in the mount and into the wall at a height you like. Adjust the string length as necessary by adjusting the knot positions under the pedal, and you're ready to go! Dispense by pressing down on the pedal while your hands are under the nozzle.
I used some braided nylon cord from an old blind. But the string is non-critical - use whatever you have on hand, it just needs to be strong and not too stretchy.
Note: this mount is for a bottle that is 3" (76 mm) in diameter. If you have a larger or smaller bottle, that's OK. Just rescale the wall mount print in your slicer to match the bottle you have (e.g. for a 4" bottle, scale by 133%, or for a 2.4" one, by 80%). Just make sure you buy a dispenser bottle which is round and has one of the large plungers (like this one). Or just loop the string over the plunger head (see next step).
For a more robust pedal, just get a piece of plywood and drill a couple of holes in one edge. Pass the cord through and knot.
Step 3: Alternative Model
I made a second dispenser with a different style of bottle. For this one, I also 3D printed a cap for the plunger because it was not large enough to thread the string through (the cap takes care of that task). If you have a bottle like this one, it might be useful. The pedal is the same as the one in the previous step.
Step 4: No 3D Printer?
No problem. Here's how we made a prototype out of scrap wood, string and a piece of tubing. It works just as well as the 3D printed one, though it looks a bit less slick. We cut a hole the same size as the base of the bottle in a piece of 3/4" thick wood using a spade bit and a jigsaw. We glued two triangles underneath to brace the shelf and support the bottle. We trimmed it down a bit to make it a bit slimmer. We drilled two guide holes in the shelf, and looped the string around the plunger, through the guide hole, through the tubing, and back up the other side. Another loop is secured over the plunger. We realized after making this one that the larger plunger heads would be easier for securing the string on the plunger, which is why the 3D printed one uses a different bottle.
Step 5: Make One!
Go make one yourself - I'd love to see your takes on the design.