Step 1 The mold is now ready to cast
With the clay removed and the cleaned female side, the mold is now ready to cast the first part of the two color casting. This lens uses 35G of both A and B of Alumilite Water Clear and to achieve the right color for the brake light half of the lens. 4 lines 7/8" long on the spatula is used to achieve the right color for each casting. The spatula with the red dye is then rubbed against the side of the stir cup after the two parts are poured together. Not all the dye will come off the spatula, but enough to create the correct color and each lens is the same.
Step 2 The blocking part of the mold has been
Here the blocking part of the mold has been removed and as you can see the blocking of the resin into the top half of the mold has been effective. The PVC piece was put between the red and amber halves of the mold to keep resin from filling up in-between the two mold parts where the styrene piece was inserted when making the mold. Although very thin it will still take a large amount of resin to fill the space between the two mold parts which is not wanted.
Step 3 Removed blocking mold
This shows the blocking mold just as it was removed from the top half of the lens mold. The PVC piece is still in place and the red resin has made it’s way all around it.
Step 4 Peel the PVC piece
Here the PVC piece (that was inserted before the resin was poured into the mold ) is peeled away
from the red side of the mold with little effort (the PVC piece was trimmed so it did not go all the
way up to the sides of the female part of the mold) This was done to make sure there will be red cast
for the Amber to adhere to when the second half of the mold is poured.
Step 5 Clean up
Now, clean up is necessary and by using a small nipper to cut away flash and extra resin that builtup
because the insert was not all the way out to the edge. If your mold allows you to have the PVC insert go all the way out to the sides and bottom of the mold then there will be less clean-up. Make sure there is available casting for the other side to attach itself or there will be two parts instead of one.
This picture shows how easy the upper half of the mold was to clean up after using the blocking mold.
Step 6 Measure dye
The same amount of Water Clear is used for the upper part of the lens. But only one line 7/8"
long of orange dye is used to achieve the correct amber color. Again the spatula with the orange
dye is then rubbed against the side of the stir cup after the two parts are poured together. The
red half of the mold has some residual heat, so only the male side for the amber part of the
mold is heated in the Microwave for 50 seconds.
Step 7 Remove the flash
After curing in the compression pot for 2.5 hours the top half of the two color casting is complete. Note there is flash to be cut away where the styrene piece was used to make the mold but it is thin and can be removed with a nipper to make a smooth cut.