Link to PART 2 - Casting the Urethane Part:    • Great Video: Casting a Part With Poly...  

Making a 2-Part silicone mold is an essential skill to learn for casting polyurethanes. Using simple methods developed over several decades in Rapid Prototyping, learn how to make a silicone mold that produces high quality parts.

For 40 years, BJB Enterprises, Inc., an ISO 9001:2008 Company, has been in the business of formulating and supplying quality liquid resin systems to a vast array of industries and with a myriad of applications in mind!

BJB offers a complete line-up of Castable Polyurethanes, Epoxy Systems, Silicone Casting Rubbers, Polyurethane Foam Systems, Aliphatic Water Clear Urethanes, Sprayable Polyurethanes, Pigments and Release.

Be sure to visit our website:

www.BJBEnterprises.com

0:00 Introduction
0:47 Rigid Plastics
0:52 Rigid & Flexible Foams
1:08 Two Part Silicone Mold
1:55 Primed and painted with clear auto paint.
3:25 Double-Sided Tape
4:28 Cut Thin Strips of Tape
4:33 Apply Thin Perimeter
4:39 Measure & Mark Master
4:49 Peel Off Backing & Place On Splitter
5:10 Fill with Modeling Clay & trim with Shaping Tool
5:46 Feathered Edge
6:04 Demold clean part simulating an injection molded part
6:17 Styrene Sheet
6:32 Fasten with glue or tape
6:51 Pre-Molded Keys
7:57 Building Blocks
8:02 Large Diameter Pipe
8:14 Silicone can form a mechanical lock on rough surfaces
8:22 ABS Plastic Sheet
8:50 Making walls too thin can cause distortion
9:02 Mold box with clamps incorporated
9:11 Hot Glue to Splitter Board
9:37 Tin Catalyzed (condensation cured)
10:12 Sulphur Containing Clays
10:27 Run Small Test on Unknown Surfaces
12:25 Use a mixing container with plenty of room for expansion.
13:14 Continue pulling vacuum for several minutes.
14:39 Aerosol Spray creates a texture
15:38 Plastic Rod
15:53 Provide Make-Up material from shrinkage.
16:24 Vent Risers
16:51 Risers decrease wear on the mold
17:14 Equipment Injection
17:32 Placement of fill port & vents is a critical detail.