A box with 3x4 keypad holes

Thread Starter

mike_canada

Joined Feb 21, 2020
239
I have purchased a few of these keypads and I built a circuit with the keypad and LCD. Both are in fixed positions and attached to the board via short jumpers to make things clean.


The store and datasheet can be found at:
https://futurlec.com/keypad/keypad3x4w.shtml

The objective is to protect the circuitry from outside elements while still using the keypad and seeing the contents of the LCD, but when I search for project boxes, I don't see any with squares cut out to fit the buttons through. The closest thing I saw so far are waterproof boxes with transparent tops. That helps with LCD viewing but doesn't help with the keypad.

Is there a box specifically designed for what I'm trying to achieve? if so, what is the name for it?

And if that's not an option, then is there a mini box which is designed just for keypads like this then I may have to use two boxes: one designed for the LCD and one designed for the keypad.

The LCD in question here is a 16x2 character LCD.
 

SamR

Joined Mar 19, 2019
5,039
We used clear elastic button covers on our plant desktop phones in the operating areas of the plant because we were manufacturing gummy resins. No idea where they came from but they were simply designed to use on phones and had to be changed out periodically. I like the membrane pads but under heavy wear conditions the numbers wear off and the whole pad must be replaced. That still leaves the LCD to deal with. I think I might go for clear plastic tearoff cover sheets for that. The button covers were taped down with fiberglass reinforced clear tape and looked pretty crappy but did their job for several months between replacement. Certainly cheaper than having to replace the entire phone regularly because the buttons were gummed up and sticking.
 

Thread Starter

mike_canada

Joined Feb 21, 2020
239
Sorry I wasn't clear.

By outside elements, I meant things outside of the circuitry itself like dust, airborne elements, etc. I didn't necessarily mean rain.

The circuit will be running indoors but people of all ages will eventually be using the keypad frequently and some fingers may be dirty and eventually I want to be able to clean the unit with a cloth and non-harmful cleaners without causing the internal circuitry to malfunction.

If I do not have sufficient covering, then surely the circuitry will be destroyed because water conducts electricity and can cause short circuits. I don't want to have it where I wipe down my unit and wait several hours for it to completely dry (which is why I could use plastic covering).

And to the guy who thought of elastics... its not a bad idea. Maybe I'll need super thick elastics like they used in old-fashioned big box floor humidifiers (the one that comes with a giant drum) then if I do that, would there be boxes I could buy outright that has a rectangular hole so all the keys can fit through?
 

MisterBill2

Joined Jan 23, 2018
18,463
I have seen those keypad covers on phones and they do work. And I have used PLC programmers with membrane keyboards that work for a couple of years. So I suggest a membrane keypad. OR a much more durable idea, individual sealed push buttons mounted on the panel in their nice round holes? The LCD with a cutout and a lexan window. The smaller buttons would allow a keypad similar in size to a phone keypad. OR seek out that sealed keypad comapny that made them for the original automotive cell phones. IIf you need thousands of them the keypad folks will be happy to work with you, if you only need ten, not so much help.
 

MrChips

Joined Oct 2, 2009
30,795
It depends on how many units you need to build.

Here is a design I did for a client. It uses an off-the-shelf Grayhill 4x4 matrix keypad and 16x2 alphanumeric LCD display.
The metal box is covered with a self-adhesive polycarbonate graphics overlay making it dust and weather proof.
It is easy to clean by just wiping with a damp cloth.

Orchard Monitor.jpg
 

MisterBill2

Joined Jan 23, 2018
18,463
It depends on how many units you need to build.

Here is a design I did for a client. It uses an off-the-shelf Grayhill 4x4 matrix keypad and 16x2 alphanumeric LCD display.
The metal box is covered with a self-adhesive polycarbonate graphics overlay making it dust and weather proof.
It is easy to clean by just wiping with a damp cloth.

View attachment 257877
I used to be able to get those panels printed at Kinko's.MUCH cheaper than engraved lamacoid.
 
Top