Condoms Dispenser

Our college's nurse requested an affordable condom preservatives dispenser. Here it is! It is made out of acrylic (PMMA aka plexiglass) and the top and lower parts are 3d printed. The condoms packagings shown in the pictures are round but the dispenser is also compatible with «standard» square ones.

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Materials

26 metres (77 grams) of 1.75 mm diameter 3d printing PLA filament for the top and bottom parts

A 360 x 295 mm sheet of 3 mm thick white acrylic for the walls

A 76 x 360 mm piece of 3 mm thick transparent acrylic for the window

A 65 x 65 mm piece of 12 mm thick transparent acrylic as a weight

2x M3 x 6 mm long button socket cap screws they could also be tamper proof screws...

4x #8 wood screw for mounting the dispenser on a wall

Methylene chloride (aka dichloromethane) for gluing the acrylic parts

Epoxy glue for gluing together acrylic and PLA

Masking tape to help during the assembly process

Tools

A M3 tap for making the threads in the holes

Access to a laser cutter

Access to a 3d printer

A small and cheap paintbrush with natural bristles (synthetic ones would be dissolved by methylene chloride)

3d print the upper and lower parts. 3mf files are supplied and also an Autodesk Fusion 360 (.f3d) native in case you want to make some design changes. We used PLA with a 15% infill with a 0.2 mm layer height.

All laser cut parts are included in the .svg file. First let's cut the side panels in white 3 mm acrylic

Dry assemble the side panels (the white parts) and keep them in place using masking tape.

Add the two 3d printed parts on each end but don't glue them right now : use masking tape instead. Those parts will help to keep the assembly square during the gluing process.

Safety first! Methylene chloride is a highly volatile chemical and is dangerous for skin, eyes, liver and heart. Use it in a well-ventilated area and read the safety data sheet of the product.

Pour some of the solvent into a glass container (and close the bottle right afterward!).

Dip the paintbrush into the solvent then apply it in one pass on the edges of the assembly. Resist the temptation of making more than one pass: the plastic has been softened by the solvent and a second pass would make ugly marks.

By the way: methylene chloride appears to be a good solvent for PLA (3d printing filament) too, it could be used to glue the side panels to the 3d printed parts but I don't recommend that option. Since methylene chloride is a solvent, it will evaporate and the parts that are not "mating" perfectly might be weakly glued. On the other hand, epoxy doesn't loose volume as it polymerizes so it would be more efficient at filling the small gaps and giving more strength to the whole assembly.

You might also want to glue everything with epoxy, that's an option, but methylene chloride will give a much cleaner result.

I won't detail how to use a tap, there are plenty of instructions for that. But! If your instructions implies the use of a power tool for tapping find another tutorial! Tapping (even in hard material) is easy to do by hand. A tap is made with very hard steel therefore it can snap easily. Tapping manually will give you more control of the tool. You don't need a lubricant : that will spare you some cleaning afterward.

So! Let's glue the 3d printed upper and lower part with epoxy. Secure the parts in place with masking tape.

There is a small gap between the back panel and the lower part so it can still move on the y-axis. So take care to place it so that the two surfaces at the back are coplanar.

Some weight needs to be added on top of the stack to prevent some "jams" mid-height of the dispenser. We tried using a strip of flexible PETG but it made the refill process more tedious.

We used laser cut weights made out of 12 mm thick acrylic. You will need from 1 to 4 of those weights. Unfortunately, laser cutting such a thick material is not a piece of cake for many laser cutting machines.

Transparent weight has the advantage of not masking the brand of the product.

There are four holes on the backplate of the dispenser. I presume you figured out that they are intended for screwing the apparatus to a wall. Those holes are for #8 wood screws. Don't apply too much torque : the acrylic panel is easy to break...

There is not a lot to say on that step! Place the condoms in the dispenser then add the weights on top of the stack.Close the machine using the transparent front panel and secure it with the two M3 x 6 mm long button head cap screw. In our school, those "Allen" sockets screws are enough to prevent tampering, maybe you will need something more tamperproof...

The dispenser have a capacity of around 60 to 70 condoms.

Have fun preventing infections and unplanned pregnancies!