Enclosing your project, the pursuit continues
December 10, 2011 7 Comments
In a previous post, I discussed my journey to enclose my projects. I have been thinking about this question for a while. Recently I developed my serial LCD keypad backpack, specifically to make the difficulty of creating a user interface goes away. Now it needs to be mounted. So I devised a plan to create a physical user interface with appropriate project box for LCD projects. Here is a finished picture, not too bad, right?
Here is a list of materials needed:
- Box enclosures brand enclosure from allied electronics
- Optional rubber protective boot
- 4*4 membrane matrix keypad
- 16X2 character LCD
- Optional serial LCD keypad backpack
- Some screws, nuts, and standoffs
Here is a list of tools needed:
- Dremel handheld rotary tool (includes a small cutter and a few abrasive disks)
- A couple of drills (1/16 and 1/4 inches or 1mm and 3.5mm)
- Utility knife or just a cutter
- LCD printout
- Screw driver
My choice of enclosure has an advantage:the enclosure has a 9V battery compartment :). If you decide to not buy my serial LCD keypad backpack, then there will be 20 wires between the front panel and inside the box, 8 for the keypad, and 12 for the display. You may want to use a ribbon cable or jumper wires. If you do get the backpack, you only need 4 wires instead of 20 plus the programming is much easier with the backpack. So your choice.
Cutting and drilling:
First, get a precise layout of your display including the PCB boarder, screw hole and size, and display area. I suggest you print it out on paper or draw it on paper. Make sure you check the actual display instead of solely relying on the spec sheet, which could be different from your display.
If you got the serial LCD backpack, you can download this file and print it out. Cut out one display diagram. Read this spec sheet, maybe it’s the same as yours so you can also use this file. Whatever way you get the layout, use double sticky tape and secure it symmetrically on the front of the enclosure, leaving some space above it, maybe 1/4 inch or 6mm.
Now use the dremel abrasive disk and carefully cut along the inner rectangle, or the dimension of your display’s viewable area, not the entire black frame. You want to be careful not to over cut. You can try to cut from the under side to help you remove the window. Once you’re done cutting, use a knife to free the four corners.
I messed up the top edge of the box a bit by getting the spinning chuck too close to the edge. No big deal. Now you can use the dremal cutting tool to cut the four corners. Here is the under side.
Now use the smaller drill bit to drill guidance holes at the screw holes. Then use the proper drill bit to open the hole up for your screws.
Now remove the printout and excess material. Mount the LCD to see how it looks like.
Here is the back side:
See the standoff on the enclosure? That is why you don’t want to cut the window too high.
A closeup on how I mounted the display:
Basically from top to bottom: nut, display PCB, standoff, then screw on the other side.
Now cut a slot at the bottom of the box top to allow the membrane keypad connection to pass inside the box:
Just don’t cut too low. Leave about 0.5 inch or 12 mm.
Then carefully remove the backing of the membrane keypad. Pass the connector through the slot and stick the keypad on to the box:
Tada! A good-looking box that you can use for anything! I am planning to add a GPS module inside of it and run a GPS logger with it. Please see the phi-2 shield page for the GPS project code.
Now the under side:
As you can see, the connector comes back up to about the bottom of the LCD. This way you can connect the LCD serial back pack easily without stretching the cable.
Later I will add an LCD backpack to the box. The box has enough space to hold a full-size Arduino UNO and some other stuff, plus a 9V battery compartment so you are all set for an exciting project.
If you don’t have an LCD backpack, I suggest you solder a female header on the back side of the LCD so you can run simple jumper wires between the LCD and arduino. For the potentiometer and LCD resistors, solder them inline. Also use jumper wires to connect the keypad to arduino. You will only have 4 free arduino pins left. Total of 20 arduino pins – 2 serial programming pins – 6 LCD pins – 8 keypad pins = 4 pins left.