I have an UNO and a 1602 LCD Keypad shield. Like this, https://www.instructables.com/Arduino-LCD-Keypad-Shield-1/
I'm ready to put the UNO and 1602 LCD keypad shield into an enclosure, I was going to mount this on a DIY pcb with traces for in and out of the box, but looking at the Screw Shield 1.0 price, I see that is not a good use of my time.
First thing I see is the brightness pot sticks up as high as the front of the display, I don't want to put an extra hole in my enclosure for the pot, so I guess I will side mount it or put in fixed resistors.
Now, for my project I need 3 buttons to access from the top of my enclosure is there a rubberized accessory that I can mount to the top to access the existing PCB buttons or minus that, I could add 3 buttons to the top of the enclosure and wire them to the LCD PCB. Any suggestion on enclosure mounted switches. Ideally I would like a rubberized button accessory the top panel mounts and reaches down the existing button on the PCB.
See picture for what I would like to buy, other ideas are on the table.
The knurled plastic knobs can be pulled out. They each have a plastic "+" on the bottom to hold them inside the pot.
I think we have a failure of communication. I'm using the 1602 LCD Keypad Shield in the picture below. It has a 25 turn pot mounted on the pcb, no removable knob, I do recall the kit had a pot for the breadboard with a removable knob.
I can get around the pot problem by either side mounting it or fixed resistors.
My problem for today is external buttons. I suspect I'll end up mounting some switches to the top cover then making solder connections to the existing switches. But, I am holding out hope there is a product to do what I want.
Douger
What about replacing the existing switches with ones having a longer button?
... and, there are "button extenders" also called shafts.
I'll look into that, I'm hoping to make it at least water resistant. It will have a small tank of water and a pump, but pretty well isolated, but, I want to take some precautions to keep things protected.
Douger
On the projected type, second pictured switch on first page with the square top, is the square top removable? And then inserted after the switch shaft goes through the panel?
Douger
It looks like it is an integral part of the switch. That is, non-removable. Near the bottom of the datasheet is a reference to key tops for this series. From the images it appears the key top snaps onto the switch proper.
Thanks dougp, That's helpful, doesn't solve my water resistance desire, but it not overly important.
Now to solve the alignment of the display and 3 of the button registration on my front panel. I suspect I'll have to make a template, use it on a practice piece, and keep adjust the template until I get it right. 
Douger
Try 'ip67 pushbutton'.
Unfortunately or fortunately, room is too tight for reeds switches.
I think 13mm tall switch will work just fine. I want round covers (caps) .
I have a lack of knowledge, this page has caps for the switches, but the mounting hole are square, are the square hole buttons used to mount on round switch shafts?
I'm probably looking at a slightly unconventional mounting, as I would like the switch cap to cover the hole in the front panel, so, I want need no cut outs or flanges on the cap.
The 1602 LCD Keypad shield switches mounted on the pcb, do not have symmetrical or even good alignment, so my hope is to hide misalignment of the holes with the cover.
Here's the switch I'm looking at but not dedicated to, https://www.digikey.com/en/products/detail/e-switch/TL1105DF160Q/271562. I want a cap like this, Last switch on bottom right, https://omronfs.omron.com/en_US/ecb/products/pdf/en-b32.pdf
Yes, I'm aware two different manufacturers, and the switch shaft diameter is 3.5mm and the hole in the cap is 3.55mm to 3.88mm, I think it is tapered. This is the style I want, but so far haven't found compatible components.
When I've tried to stick with one manufactured, I don't find the styles I want. i.e. 13mm and round top with proper mounting hole.
Any have better search skills to help.
Attached are a couple of pictures that may or may not help.
I have also added the template to print for marking a front panel for use with the 1602 LCD keypad shield. Note: may need to resize it as each printer is different.
Douger
Is a flat membrane type switch not desirable?
Not sure I understand the question. Do you mean like is already on the pcb?
If that is what you mean, I'm mounting the 1602 LCD keypad in an enclosure and I want
to be able to access the buttons. So, I need a switch with a taller height, 13mm. I plan on staying with the tactile membrane type switch.
Thanks, Douger
Well, I had something more like this in mind.
Membrane switch
I'm not familiar with that, and not sure it would just plug into my 1602 LCD Keypad Shield.
I would also need to change my program if that is not a resistive divider switch arrangement.
Thanks, Douger
You are in control, designs should be flexible prior to manufacturing.
It's a one of circuit! The pcb I have uses switches on resistive divider feeding one analog input. I suspect that switch assembly uses four analog inputs.
Douger
That's just an example of the kind of switch I'm talking about. I believe that one is a matrix with a common lead. They come in all configurations and there are SPST versions that could replace your switches. It was just a suggestion as a way to accommodate a flat, waterproof design. I've used them for half a century in various products.
Ya, no problem, there are many ways to solve a problem. Early on I bought a pcb that had the LCD and several switches that I could use for setting up heat and water scheduling. The switches do their job, and if they were taller, all would be great. I'm a little surprised that no one seems to have developed a mounting panel to use with the 1602 LCD Keypad shield, I see there are 1000s being sold, but, it does seem physically difficult to design a panel to use because the buttons are too short to reach the height of the piggyback LCD pcb. All I need to do is replace 3 short stem switches with longer stem switches. I don't really need caps on the switches, I just expect my panel cutting might not be perfect and the caps will hide imperfections.
Thanks, Douger