No-shrink-pink,share and help us all out.
A little story. You make rubber molds every day, usually of
customers merchandise that they want duplicated for whatever
reason. The catch is the shrinkage, usually a noticable amount,
really noticable when the customer compares it to the original.
The job is then returned to you from the jeweler with a note,
its smaller please redo at no charge, Ugh. Your response, several
years ago, was the well the advertised no-shrink-pink rubber. Now
instead of carving 99.9% of our custom jobs maybe you would only
carve 80%, mold the rest, save time and money, retire young (or
at least retire someday). Wrong, the vulcanizer that you had
bought from a freind in 1985 for $100.00 had always served you
well, until the day no-shrink-pink entered your life. In the ad
for this super rubber they show the original ring and the wax of
the NSP molded ring each on a mandrel each exactly the same size,
demonstrating no shrinkage. The procedure is to make sure each
plate on your vulcanizer is exactly 310 degrees, you can do this
by putting a block of wood between the two plates and inserting a
metal thermometer between the wood and one of the plates. When
you hit 310 F. you check the other plate, it is very unlikely
that the other will be the correct temp.. So you get it as close
as you can, cook your mold for exactly 7.5 min. per slice, and
guess what, it didn't work! You try and try again and always have
shrinkage. That is until that day that you get that job, the
mother of all carving jobs, you have a month to duplicate it
because they know its too difficult for a 10 day turn around.
This time instead of waiting until 5 days before its due to start
it, you order a brand spankin new vulcanizer with separate temp.
controlls for each plate (Gesswein about $600.00). You still
check each side making sure they are each 310 F., you cook for
exactly 7.5 min per slice and guess what, it still shrinks, but
not very much. After several molds of the same ring and
adjusting up about 4 degrees, it works. Life is good.