Materials/Tools for Step 1
✦ RR-Foam Core Mold w/3/8” Mandrel
✦ RR-6# Pour Foam: Part A & Part B
✦ Release Agent
✦ Digital Scale
✦ Paint Mixer
✦ Black Pigment (make grey foam core)
✦Open up Foam Core Mold and remove 3/8” mandrel.
Note: The Mold’s label is your guide to align and reassemble the PVC halves in subsequent steps.
✦Spray 3/8” mandrel with Stoner Urethane Release Agent (light coating; mandrel
seasons over time, vaseline also works just wipe on a very light coat).
Note: Don’t spray release agent in your work area and wash hands after using! We learned the hard way after
slipping on the stairs and braking a dinner plate or two!
✦Insert 3/8” Mandrel back into silicone rubber mold. The end of the mandrel at the
base of the rubber mold should stick out a 1/4”. The rest of the mandrel sticks out
at the top.
✦Lay silicone rubber mold on one half of the PVC; the opening of the silicone rubber
should face up; make sure PVC and rubber mold are straight.
✦Measure and pour 28g (1oz.) of Part A into a cup; measure and pour 28g (1oz.) of
Part B into the same cup. We recommend using a plastic cup on a digital scale to
measure Part A and Part B.
Note: Temperature greatly affects expansion rate. Best temperature is 72°-78°. If working in
lower temperature use 1g/ml more of each Part A and Part B; in higher temperature use
1g/ml less until you’ve determined the correct amount.
✦ If you want to make a grey core use 1-2 drops of black foam pigment. (any more will inhibit expansion)
✦ Mount paint mixer on drill. Mix on HIGH speed (1200-2400 RPM) for 18-20 seconds.
This liquid mixture is called a cream. POUR IMMEDIATELY as foam will expand
momentarily and enter the gel phase.
✦ Working quickly as you have 20 more seconds before full expansion starts:
‣Spread opening of the silicone rubber mold with your fingertips
‣Pour all the cream into the center of the mold
‣Keep mold horizontal (do not rotate)
‣Place second half of PVC on top of the mold
‣Align PVC halves using label as guide
‣Slide velcro ring onto PVC and put on end caps (black end cap goes on the left side–when label is right side up/correctly positioned)
✦ Leave for 40 minutes for full cure.
MAKE THE FOAM CORE
✦ Pot Life: 40 seconds*
✦ Set-Time: 7 minutes*
✦ Full Cure Time: 40 minutes*
*Pot, Set, and Cure Times are for Riley Rods RR-6# Pour Foam and RR-321 Epoxy. If using different products refer to their specifications. Read and follow product label directions and warnings; read MSDS for detailed product safety information prior to use.
Clean-up: Part A cleans up with acetone; Part B cleans up with water. The mixe foam product is
very adhesive, so use with care. To remove mixed foam let it fully dry and then chip off.