Dry Erase Board

I had a few days between classes summer of 2002, knowing that I was going to be in calculus soon I thought a dry erase marker board would prove useful. I looked at a few office supply stores and the biggest one that I had room for was 36"x48". After having it on my wall for a few days I found it lacking.

The first thing I wanted to add was a new marker tray. I found a 4" piece of steel channel that had a 90 degree bend in the middle (it was free). I cut out a 90 degree "V" in the middle of the bend to get it closer to a straight line, I wanted to make this a feature so I dressed it up with some custom made steel brackets and two 6.25" bolts.

Another feature that I wanted was a place to post papers; I have a collection of rare earth magnets glued onto old Intel processors so I used a piece of steel plate .125" thick to provide this service.

I wanted to build in some lighting, something that could be used for atmospheric lighting, so that I could sleep with the light on. I had about 50 red and blue LEDs, not the radio shack verity but 7000mcd (mille candela) the same found on key chains. I backed the lighting with broken mirror to increase its respected output. Random lengths of acrylic round stock were placed into holes drilled through the EMT then bent with a propane torch. After this was done each LED was attached using clear heat shrink tubing. The LEDs butt up against the ends of the acrylic, any imperfections in the plastic allow the light to leak out. I added the needed imperfections by gently heating the plastic rods until small bubbles started to form. The light follows the same principles that allow fiber optic lines to work (internal reflection) Ten foot sections of wire were soldered on to the LED's legs then cleaned up with more heat shrink tubing. My friend Kelly was kind enough to do a fancy braid to clean up the strands of loose wire. Because I had just finished trigonometry I wanted to incorporate a sine wave into the electronics (visually). I drilled the holes for the resistors in a and soldered them on to the plastic, I also soldered on a toggle switch and connector for the power supply. I drilled a hole and left room for a potentiometer but never installed it due to the $30 price.

All metal surfaces were sprayed with an auto body clear coat prior to installing the lighting and marker board. This maintains the level of rust currently on the steel, A wire wheel could be used to clean up the metal before the clear coat but I preferred the rusted look. Make sure to knock off any lose material before applying 5-10 layers of the clear coat.

This whole project was built with materials on hand except for the power supply and the dry erase board. I spent about 15 hours from start to finish over three days on this project.



Materials list:

4' x 5' .75" plywood sheet
18' x 1" half round pine stock (edging for the plywood)
4" x 4' steel channel (marker tray)
1' x 4' .125" steel plate
4' x 1" round EMT

36" .25" threaded rod (mounting the EMT)
12 - 1" x .25" lag bolts
Other bolts to taste

800 feet of 24 gauge wire (stripped CAT-5 works great)
40 - 220 Ohm resisters
12v 1 amp power supply
toggle switch

12" by 5" plate of clear Lexan (polycarbonate)
30' of .25" clear acrylic round stock

1' x 4' mirror
36" x 48" dry erase marker board