1. Introduction

     Hi! This will be a follow up blog to my first big button blog Custom Big Button V1.0 . In that blog I wrote about how I designed and printed out of PLA a big mechanical button which would use a small button inside for the electrical connection. The button turned out pretty good, but there are some things I wanted to change, so here is how that went!

 

2. Idea & Plan

     Overall, I was pretty happy with the size of the button and the plastic nut I printed for securing it down to surfaces. I was also happy with how the lettering looked on the button, though, a brighter color would look much better than this one. The only thing I wasn't really too happy with what was how the button performed. Did it do what it was supposed to? Yes, but not that well. The travel is way to short to have a satisfying feel to it, mostly due to the bad small off the shelf button, which had the travel it had, and also because in the end, this is 3D printed, it's not injection molded or turned on a lathe, so the tolerances aren't that amazing. This causes problems when you press the button off to the side a bit, the whole thing can swivel a bit, and it's corner will hook onto the wall of the outer case of the button. With that in mind, here is what I changed on the button. Instead of the small red button I went with a keyboard switch and I went with a longer button but with the same diameter. The keyboard button has a lot more travel, around 4mm and feels much better than the plain small red button. The longer button will help in the sense where you won't be pushing into the side of the house when pressing off center as much as you would be when pressing a shorter button. I'll get into more details and measurements in the design part of the blog.

 

3. Design

     In this part of the blog, I will show you how I designed this version of the button, guided by the design of my last button. I won't be going through the design of the nut, spanner and the template, you can find those here: Custom Big Button V1.0

Switch & Spring Choice

Here is the small switch I went with last time:

This time, because of the too short of a travel, and in general because there wasn't any satisfying feeling to pressing this button I switched to a keyboard switch and a larger spring to accommodate the switch. This small red button has a travel of 1.5mm while the keyboard switch has a travel of 4mm. Here are the components I used for this button:


I can't remember exactly where I found this spring, I think it was maybe a part of a battery holder for D type cells, but I really can't remember for sure.

Top

     To stabilize the button better than the first one was I went and made a longer top part of the button. This would have drastically improve the V1.0 without even changing the switch and spring, but in this combo, it's much better. As I've already said, the longer button means that, if we don't press it on dead center, the button may go into one of the sides but at a much lower angle, meaning it will drag much less, as I will show later with the finished button.

The design itself is really similar to the old version. The old button was 13 mm long from top to bottom, while the new one is 33 mm, which is a significant improvement. The diameter stayed exactly the same. The very top of the button which we can see is 5 mm on the old button while on the new one it's 11 mm. This is to accommodate the longer travel and to make it look a bit better, which leaves the lower cylinder which is used to guide the button to go from 8 mm to 22 mm, which showed excellent results.This is the only part that went through a bigger redesign, all other parts just had to follow along to fit with this part of the button.

Body

     The body of the button was pretty much the exact design as the last one, just of course, longer. I made a same thread on the outside as last time, so I could use the same nut for both buttons. Besides that, there really aren't any changes.

 

Bottom Plate

The bottom plate was also designed like last time, like an end cap with the mounting hole for the switch. I looked online for mechanical keyboard switch holders which look much better than my solution, but through testing I found that square hole of proper dimensions can hold the switch amazing, the switch just clicks in, to be safe, I added a bit of glue, as for the spring, I just left some grooves for the spring to sit in so it doesn't move around a lot and gives a more consistent feel to the use of this button. I used a bit of super glue in the end to attach the bottom plate to the body of the button

 

4. Finished Button

     With all of the parts finished and together, here is how the finished button turned out:

I love how this button turned out, specially with the orange color instead of the dark green, the letters look much better like this, also how much further the button top goes out than the last one. Here is a video of the button being tested:

 

I'm really happy with how it works. It has a really nice and satisfying feel when pressing it, and a lot of travel. It still has a bit of a grinding sound when pressing due to both surfaces having 3D printed layers, but it works even if I press on the edge of the button, which I really couldn't say for the V1.0. Here is how they look and compare to each other.

 

5. Comparing to the V1.0

 

 

 

6. Summary

     While both buttons work and do the job just as well I will be sticking to the second option, it just feels better and works a bit better. I will switch to the old version if I have a space limitation where the newer button can't fit. This version of the button will for sure find a couple of places in some of my upcoming projects about which I will write here. There is one thing I would like to try with making these buttons and that is the third option I talked about in the previous blog, it's making my own switch instead of using off the shelf ones. Of course that would mean I wouldn't have a rating for it, but I'm not planning on using this on anything more than 12/24V so I won't go to any high voltages or high currents. The reason Why I would like to do another version is so I can switch from a soldered connection type to a screw connection. I'll also try maybe printing an add on for this buttons which would have screws which are internally soldered to these switches to accomplish that. Thanks for reading the blog, hope you liked it!

 

Milos