Timing Belt Pulley Casting.
See pictures on: MijnAlbum
Construction of the mold:
Cut a length of the teeth belt equal to the number of teeth of the required pulley.
Trim both ends to exactly fit the tooth distance.
Use a lathe to make the piece of belt fit tightly the inside of the casting tube.
Make bottom and top with filling holes and a shaft to get fixed to the pulley or make room for bearings.
Grease the outside of the tooth belt an put it in the tube.
Clean the excess grease from the tube.
Apply the liquid release agent on the basis of poly-vinyl-alcohol and water(Lossing B-film)
part and let it dry.
Mix a bit more epoxy then required.
Use a small amount to mix in 10% of graphite powder.
Use a small soft brush to put this mix on the teeth belt without spilling it.
Place the tube on the base plate
Mix the rest through the the epoxy and fill the mold just below the top.
Put the lid on slowly fill it up and tilt a bit to prevent air bubbles.
Safe the rest of the epoxy on a cool place to top-up after while due to the crimp of the mix.
When ready, scrape the teeth's
with a saw blade cut into shape.(see pictures)
To give the belt more room between the teeth's due to the exact fit.