The spring

A project log for Mini vending machine

A well documented miniature vending machine. It uses login/password or RFID to "sell"

Gabriel D'EspindulaGabriel D'Espindula 04/22/2019 at 09:150 Comments

It supposed to be simple and actually can be super simple, but my personal challenge here is create some reliable method to fabricate this spring. To be more precise, I want the following features:

Well, so far I've got a few options and didn't like none of them.

The first one would be using some steel wire and wrap in some sort of tube.

This is quite obvious but as pointed, my goal is something more reliable and not crafted. And to properly make it, the wire must be ticker to avoid wobbling or bending over time. May even be necessary a heat treatment to "save" the wire format and increase the hardness of the spring.

A possible solution would also fabricate a mold or template to facilitate this wire wrapping, but I didn't try that yet. I admit that it might be my final solution, but I still looking for a better solution.

The second option would be doing some mdf or acrylic spiral

Issue is the limited size for it. May be good for this small version, but a parametric design should consider some bigger versions using the same method. I also believe this is quite easy to break.

The third option is my next try. Basically would be 3d printing a spring. 

I think about some modular spring that can be connected if the design required a long length. I'm afraid of the fragility of the print and wonder to coat after print to increase the layers bond, I'll update this log after trying out.

Well, the fourth method was my first and terrible try.

I was trying to somehow assembly laser cut parts to create a spring, but it didn't work at all. I still believe laser cut parts could assembly a spring, but couldn't think about a good shape.

If somebody has a good suggestion, I still up to hear it, I'll also try my best to keep it updated and finish it as soon as possible!