Molding Foam | McMaster-Carr

Filter by

Cell Type

Flexibility

Density

Material

Weight

Foam Expansion

Thickness

Width

Color

Shape

REACH

DFARS Specialty Metals

Exempt

U.S.–Mexico–Canada Agreement (USMCA) Qualifying

Yes

Machinable

Yes

Export Control Classification Number (ECCN)

RoHS

Form

Maximum Temperature

Cure Temperature

Time to Demold

Time to Cure

Performance

For Use With

Cell Structure

Melting Temperature

Minimum Gas Evolution

Help me decide (beta)

17 Products

Foam Casting Compounds


Compound expands to fill every hole and cavity.

Create lightweight molds with these two-part compounds. They expand as foam after they’re poured to fill every cavity. The denser the foam, the less it will expand. Before casting, apply petroleum jelly (not included) to prevent sticking, stretching, and tearing. It won't cause the foam to collapse as it cures.

Flexible—Flexible compounds cure into soft, open-cell foam, which absorbs water, air, and gases. They are often used to cast gaskets, cushions, and other bendable objects.

Rigid—Rigid compounds form stiff, closed-cell foam, which prevents water and air from flowing through the part. Machinable, they’re dense enough to create prototype modeling blocks, so you can test setups without wearing down tools.

	Density, lb/ft³	Time to Cure, min.	Time to Demold, min.	Cure Temp., ° F	Max. Temp., ° F	Shrinkage	Color	Mixing Req.	Wt., lb.		Each
Polyurethane Foam





	White

		Flexible—Not Machinable

		4X	12	3	25	25	80	125	Not Rated	White	Yes	3	8866N206	000000


		4X	12	3	25	25	80	125	Not Rated	White	Yes	12	8866N26	000000
		8X	8	3	25	25	80	125	Not Rated	White	Yes	3	8866N205	00000
		8X	8	3	25	25	80	125	Not Rated	White	Yes	12	8866N25	000000
		15X	4	3	25	25	80	125	Not Rated	White	Yes	3	8866N204	00000
		15X	4	3	25	25	80	125	Not Rated	White	Yes	12	8866N24	000000


		Beige

				Rigid—Machinable

				2X	20	3	15	15	75	85	Not Rated	Beige	Yes	16	8866N23	000000


				7X	12	3	15	15	75	85	Not Rated	Beige	Yes	4	8866N202	00000
				7X	12	3	15	15	75	85	Not Rated	Beige	Yes	16	8866N22	000000
				19X	4	3	15	15	75	85	Not Rated	Beige	Yes	4	8866N201	00000
				19X	4	3	15	15	75	85	Not Rated	Beige	Yes	16	8866N21	000000

Impression Foam

Stiff yet moldable, this foam takes the shape of any object that's pressed into it. In addition to making molds, it’s also used for packaging to keep uniquely shaped items in place. It comes in a package of two sheets.

Smooth Texture

Closed Cell—Restrict water, air, and gases from being absorbed.

Temp. Range, ° F	Cell Type	For Use Outdoors	Density, lb/ft³	Pressure to Compress 25% (Hardness Rating)	Tensile Strength	Pkg. Qty.		Pkg.







1 1/2" Thick

12"	6"	Pink	0 to 100	Closed	No	2.6	2.8 psi (Ultra Soft)	Not Rated	2	2222N11	000000




		2" Thick

		14"	6"	Pink	0 to 100	Closed	No	2.6	2.8 psi (Ultra Soft)	Not Rated	2	2222N12	00000

Foaming Agents for Plastic Molding Machines

Commonly used in molding applications such as injection molding and extrusion, these foaming agents reduce weight, warpage, and sinks in finished parts. Mix them into resin as 0.5-1.5% of the total mixture—by decreasing the amount of resin needed to make a part, they help reduce costs. They also lower the melt viscosity of resin so that it can be processed at low temperatures, which reduces cooling times, cycle times, and the risk of heat degradation. These foaming agents are compatible with most plastic and rubber resins.

Microfine Cell—Microfine cell agents produce smaller bubbles and a tighter cell structure than other foaming agents. They improve the appearance of your final product and keep its mechanical properties consistent throughout. They’re often used to create parts that have thin walls.

Fine Cell—Fine cell agents produce more gas than microfine agents. Use them to ensure uniform foaming when molding bigger parts.

310° F Activation Temperature and 325° F Activation Temperature—Agents with a 310° F or 325° F activation temperature are for use with low-melt-temperature resins such as polyolefins, polystyrenes, and thermoplastic elastomers.

400° F Activation Temperature—Agents with a 400° F activation temperature are for use with high-melt-temperature resins such as polycarbonates and polyamides.

FDA Compliant 21 CFR 174.5—All are FDA compliant for direct contact with food.

	Melting Temp., ° F	Min. Gas Evolution	Color	Container Type	Food Industry Std.		Each
Microfine Cell



	325	250	30 cm³/g	White	Cardboard Box	FDA Compliant 21 CFR 174.5	5469N13	0000000


	325	250	65 cm³/g	White	Cardboard Box	FDA Compliant 21 CFR 174.5	5469N12	000000
	400	350	30 cm³/g	Off-White	Cardboard Box	FDA Compliant 21 CFR 174.5	5469N14	000000


	Fine Cell



			310	310	95 cm³/g	White	Cardboard Box	FDA Compliant 21 CFR 174.5	5469N11	000000