Bezels

LCD Display Mounting

Ok, if you're here then I'm guessing you probably know how to drill a hole in a chassis. If you don't then the rest of these posts are going to mean little to you.

I am not going to go into how to drill a hole and I won't be discussing where to put controls, dials, sockets or displays - chances are, you already know what you want and where you want it. The idea of this blog is to simply share a couple of neat ideas that I have found that might make your next project a little more professional looking. I see so many builds of excellent equipment that just lack a little finesse and a few hints and tips might make the difference between an awesome piece of electronics looking awesome and an awesome piece of electronics looking like an awesome piece of electronics :) . . .

So the two most difficult items in project building, I'm sure you will agree are :-

1) Making that hole for the display just the right size so that it doesn't look ugly

2) Making the front look nice with printed decals, all in the right place

Well, today dear reader, its your lucky day. You're going to find out how to do both of those things.

You are going to need access to a few pieces of equipment but you probably have them already. If not, I'm certain you will know someone who has them.

Ok. Bezels! . . .

There are many ways to cut a hole in a plastic or metal plate. We all have slightly different ways of doing it and we all have different preferences when it comes to the materials we use. Some people choose to use the plastic fronts that come with the project cases we buy, some people choose to make their own project cases out of metal or wood. Whichever method or material you choose, I'm going to ask you to consider either switching to the one I'm going to suggest or integrating what I am going to suggest into your build. It will make life so easy.

After many many iterations and builds of many little project, I think I might have finally found my utopia - Copper clad board !!

Yes, the humble copper clad board. Not too tough that you are going to need any serious milling machinery and not plastic that you are going to have to drill mounting holes into - AND it'll give you a little extra screening from interference, either getting into the box or out of it.

Just one thing to note, you can use single or double sided board but you must make sure that there is a copper surface on the INSIDE of the panel. All will become clear later. So when designing and cutting your holes, make sure you have them at the at the right side that will allow copper to be on the inside.

Cutting the hole

Generally, I will make the front of the project case first. Usually by taking the plastic from that came with the case and tracing the same size and shape onto some copper clad board and then cutting it out with a Dremmel.

My preferred method of cutting bezel holes is to carefully measure the display I want to mount and then draw out the hole onto the front panel. I then use a Dremmel to cut the hole as near to the dimensions of the display as I can. I then finish off the rest using hand files, continuously taking small shavings and offering up the display as I go.

I used to try and get the filing exact and after many attempts, I consider my efforts to be rather good but not perfect. There is always some minor imperfection that annoys me but in the second half of this blog, you will see that you could have quite major imperfections and still achieve professional results.

Mounting the display

Make sure that the hole you have cut is large enough for the display to fit through the hole. This is an important point if you want to achieve a nice result.

Make sure that the display is in line with the bottom and top of the panel, so that when everything is in place and in use, the display isn't slanting up or down to the eye. If it is, use your hand file to shave away at the appropriate places to bring the display into alignment. Don't worry too much about the gaps that will naturally open up between the sides of the display and the panel when doing this, we will be masking all that later.

Now. Take your display and attach four stand offs in the holes on the display. Make sure that the standoff point towards the front of the display as shown, and not the back.

The length of the stand off should be just enough so that when the display is offered up to the hole, the standoffs allow the display to enter the hole but not to protrude beyond the face of the front of the panel. Having standoffs a little too long is acceptable but will mean that the display won't be quite flush with the front of the panel. This really isn't a problem as we will discuss finishing this later. However, don't have the standoffs too short or the display will protrude beyond the front of the panel and we don't want that.

Fit the display into the panel cutout so that the standoffs rest on the copper of the inside of the display.

Solder the standoffs to the copper.

Once all four standoffs are soldered to the copper, the front of the display should be almost flush with the front panel. This can be adjusted by adding washers to the standoffs if the display sits slightly proud of the panel.

The display securely mounted to the front panel and with no screws showing