Mounting LEDs to Control Panels

[elnscale]

Hi,

Looking at the choices at Mouser, for example, the choices for mounting an LED to a control panel seem overwhelming.

I have a bunch of 5mm LEDs. I would prefer them flush mounted on the panel, not sure if I want them covered in a lens or not.

Does anybody have preferred mounting hardware (preferably with part numbers) that they would recommend?

Or what you would not recommend?

TIA

Steve

[peteski]

If you use clear Plexiglas for your panels, you could install LEDs totally flush.  Here, I used 3mm LEDs.  I drilled (but not all the way through) the control panel, then glued the LEDs in from the back (using CA glue).  That way the front surface of the panel is perfectly smooth.





If your panel is opaque then you could probably find some LEDs with flat end (instead of the standard domed-end) then just drill through the panel, and use hot glue from behind to mount the LED flush with the panel's surface.

[elnscale]

Wow, Pete, that is impressive. If that's plexiglass, did you print the "layout" on it and glue it on or what did you do? If it is printed, what software created it?

That's a clever idea to drill almost through. What is the thickness of the plexiglass and how much did you drill through and how?

[peteski]

These are installed on my friend's layout.  We brainstormed this together and came up with this solution.

The material is a special sheet (designed for engraving).  It is 1/8" or 3/16" clear acrylic with a thin opaque color plastic laminated on one side.  Many colors are available. The color we selected was the off-white which makes up the background.

We used Corel Draw to design the track plan and the lettering.  We then provided that design to friends of ours who owned an engraving business.  They back-engraved the design on that laminated sheet.  The engraving process cut through the colored plastic, making the track plan and lettering transparent.  We then painted the engraved areas with Floquil paints, which colored them black and gray.  Then we drilled the holes for the LEDs and switches.  Then the LEDs were glued in and switches were installed.  We are quite happy with how these came out. 

[Ian MacMillan]

Those panels at Ernies are exactly the ones I based mine off of. Thanks for showing the inards Pete. Id also wondered for years how the track plan was done figuring they were dye sub'd, then a few years ago I found the engraver had put them up on their websire as examples of their work.



On mine I had difficulty getting the CA to adhere to the acrylic.

[peteski]

Very impressive Ian!  Nice to know that you were inspired  by Ernie's and Peteski's design. 
The engravers who did ours sadly passed away. It is good to know that this material is still available.

The engraved markings are so easy to color (since all you have to do is just plop some paint in the depressions.  the smooth outside surface also works very well.

I agree that the LED glue joints aren't very strong, but we only had couple un-glue during wiring, and no more problems after  installation. I used accelerator to kick the glue over.  We just made sure that the size of the holes made the LEDs fit tightly.

When you visited Ernie's layout, you could have asked about the panels - he gladly demonstrates how they are constructed (the main control panel simply tilts out for easy access to the innards.

[elnscale]

Ian,

That's another awesome control panel.

I don't have access to that sort of engraving work so here is my plan: I bought some lexan sheets from Home Depot which are about 1/8" thick. The size I selected was 10"x8" since I can print a single piece card that size. I will print the track arrangement and then create holes for the SPDT-center off switches and LEDs that I have purchased. Not quite sure how I will attach the card to the back of the lexan, but one thought is to use a photo frame for the whole thing without gluing. Maybe something like this onto which I can probably mount some hinges to attaching to the layout.

For reference here are the parts I have so far accumulated:

• LEDs - Green
• LED lens - panel flush mount
• O rings/spacers
• LED holders with 8" leads
• SPDT center off switch
• Lexan sheet 10" x 8"

I selected the panel mounting parts from the Mouser catalog, page 177 (guessing what would work for me) but bought elsewhere because the prices for the parts in the shopping cart were about 3 times the online catalog (I confirmed this by calling) and I found them cheaper elsewhere. They have worked out perfectly based on the test fitting I did on Friday, the day the mounting hardware arrived. I'm away for a couple of weeks so the project will startup then.

[peteski]

Steve,
that looks like it'll work.  Those LED holders are probably as flush as you will get with standard parts.  I'm not sure why go through the expense of using LED sockets. LEDs should last your lifetime - why not solder wires directly to the LED leads?  Even if you use the LED holders, you will still have to solder those wires to something.

What software will you use to design the control panel artwork? If you can't have these engraved, you could have a sign shop print the artwork on a self-adhesive vinyl film. That results in a very durable image (those are used on car exterior as advertisements) which can be applied to the front of the acrylic sheet.

[elnscale]

Hi Pete,

I've gone with the LED holders for a couple of reasons: a) they make the mounting of the LEDs on the panel easy (the point of the original post) since everything just presses together - the lens is sized to squeeze into the LED holder, clip the LED legs and press them into the holder b) I'm going to mount a wiring connector behind the panel. With the 8" leads on the holders that will make that an easy exercise. RTR so to speak.

I'll look into the vinyl suggestion. Sounds like a great idea. I know of a couple of local shops.

As for software, I'm not sure right now. I have access to all Microsoft products so something link Visio or Powerpoint may well be the way I go.

Steve