There are many published methods of coating surfaces with Mayer rods, but most describe coating only a small area on the surface. Two methods of coating the entire surface are described here to facilitate holographic emulsion coating.
method one
As shown below.
Take a glass size and decide what size dish you want to paint.
Clean and coat the entire glass panel so it is ready for coating. In the image below we are making 4 - 4" by 5" plates.
Make the full-size glass 2 inches wider (1 inch on each side) and 4 inches longer (3 inches top, 1 inch bottom).
Use a glass knife to score lines on the glass as shown, but don't break any of the lines. This needs to be done on a very flat, clean and hard surface.
Now clean the scored sides of all glass shards. Wet wipes will do. Turn the plate over. It is recommended to perform the following procedure at an ambient temperature of 80F to 90F, or heat the glass and rod with a heater (hair dryer) until warm to the touch. Also, the surface should be level in both directions.
Place the Mayer Rod (ROD) on top of the pre-stencil.
A puddle of heated emulsion is poured on top as shown, and the Meyer rod is immediately pulled down the length of the plate with uniform pressure and velocity. You'll notice the puddle stay in front of the bar and continue until you're off the bottom of the plate.
Wait until the lotion dries (this can be tested on any of the four discard ends).
Take a razor blade and score (cut) the emulsion on each fraction (the fraction is still on the bottom and you are cutting the emulsion on top).
Turn the plate over and break the score as you would with any scored glass, being careful not to let the emulsion surface touch anything. With practice, holding the snapped end in your hand and holding the fixed end over the glass cutter knob (see Glass Cutting) becomes easy. Break all the longest lengths first (top, bottom, sides then board). This gives a very even and uniform coating to each glass.
Method Two
In the next technique that can be modified for more plates, we will coat 4 - 4 inch by 5 inch plates.
Take the 4 cleaned glass plates and place them in a rectangle so that the rectangle is 8 inches wide on a horizontal surface and 10 inches down.
Now take two more cleaned 4x5 plates (puddle plates) and place them on top of the rectangle 10 inches wide. They will stick out of the rectangle 1 inch on each side.
Now use thin clear gift tape around the rectangle of the plates (not the top two, which will be used to pour the puddles on top of) and where each plate meets the other. Each of the four boards will have tape around all four of its sides. Make sure to flatten the tape nicely onto the plate with your fingers. Again use the same temperature restrictions as above (ambient or blower heater).
Place the Mayer rod on top of the puddle board.
Pour the heated emulsion into the center of the top two puddle plates and immediately pull the Meyer rods off the plates and out the ends of the plates as described above.
Let the plate sit for just one hour, then remove the tape. Let the dish continue to dry horizontally.
This also produced very consistent results. This method uses tape for some emulsion thickness (the thickness of the Meyer rod on the glass depends on the thickness of the tape), so the Meyer rod should be thinner in the above process.
notes:
Plate, emulsion and Mayer rod temperatures have little effect on coating thickness, but if any one is too cold, gelation may occur and affect quality.
Meyer rods come in different gauges, which is the thickness of the wire that is wound. Typically #40 is 0.04 inches, #25 is 0.025 inches, etc. I've found #25 to #40 to be very effective in either case, with #40 creating a thicker lotion.
Meyer sticks should be immediately soaked in warm water to prevent the gelatin from hardening on the stick, then washed in hot water and dried.
