Hello!
So I decided, as a way to improve my cad skills, that I would take an old laptop of mine and design a case around the motherboard and use it as a micro PC in my work area. I have nearly all of it designed, just shy of the power button.
On account of not having a sautering iron, I would rather avoid sautering a button on and was trying to go a more analogue approach by printing a button into the case that could maybe use a compliant mechanism to press in and come back out, but I am very uncertain how to go about it.
Any help appreciated
Compliant mechanisms are cool, I used it ones before and it works quite well. If you can get everything lined up properly that is.
All you really have to do is give the button a cutout, which is supported on only one side. Make the supporting area not too thick so it’s easy to press (1 or 2 mm should be good I think) and give the button some shape that makes it easy to feel by hand.
It’s a bit difficult to give any real tips without any pictures, but that’s the gist of what you need to do
Soldering is nothing like welding. Neither task is particularly hard, although welding takes a bit more coordination. Soldering is about as hard as using a hot glue gun or microwaving a meal, or scrubbing a toilet.
When you’ve never done it before, it is easy to build it up in your mind. Here’s the things that matter:
- acid core solder is only for pipes in a home
- flux is important and the mess it makes is not
- for just a small job, any soldering iron is fine, as is any solder
- wet everything you’re joining with flux and the solder will wick into place
- the tip of the iron should be shiny with solder before you start, and this may involve a good bit of solder added to the tip and then removed by a wet sponge or wire ball made for the task
An adjustable iron is nice, and you’ll likely find that eventually you will use it for threaded inserts in prints. There is a lot of marketing about irons and junk, but it is hard to beat the value of one of the Chinese 936 Hakko clone irons. Most of the marketing junk is to try and obfuscate the value and availability of these clones. The Hakko 900 series tips are the defacto standard and there are many extra accessory options available that are only possible with this tip/iron type. Last time I checked a 936 clone is usually under $40. The actual circuit board required to build one is under $5 on AliEx while the iron handle and lead are ~$8. You don’t need this for a basic job, but an adjustable soldering iron is a lifetime useful tool to have on hand.
Good solder makes a big difference on bigger projects when you’re doing this a lot. However, if I was in a zombie apocalypse, I could easily make a single solder connection by heating the tip of a screwdriver in a candle flame, use some resin from a pine tree, and a chip off of the pewter candlestick holder to solder a button to a circuit board.
Buttons can be a bit challenging with 3d printing design. It depends on your goals, but clearances and textures matter a lot more than it may first appear. It is possible to get something that just works, but is loose or crude. Getting a button like the inserts that go into a typical video game controller are quite challenging to clearance and develop a consistent tactile feel. I’ve done this in practice and it took a lot more iterations than I expected.
