PT4431 Aluminum Filled Room Temperature Epoxy Casting Resin


PT4431 is a gray, aluminum filled epoxy casting material that has excellent handling characteristics, and is useful for a wide range of applications. Three standard Part B hardeners are available for use with the PT4431 resin, and each hardener provides specific properties for different tasks. PT4431 is quite versatile, and can be cast from very thin sections to mass castings of more than 12 inches thick with the proper hardener. Cured castings made with PT4431 can be machined quite readily with standard cutting tools. PT4431 also provides an improved degree of thermal conductivity, due to its high aluminum content. PT4431 resin has been designed to exhibit an absolute minimum of filler settling in storage. The fillers do not “hard pack” with this system. PT4431’s thin pouring viscosity, easy machinability, cured toughness and dimensional stability provide good service in uses such as: Form blocks, Close Tolerance Parts, Drop Hammer Dies, Molds, Hammer Forms, Cast Duplicator Models, Draw Dies, Facing Metal Cores, Foundry Patterns, Holding and Nesting Fixtures

 PT4431-APT4431-BPT4431-B1PT4431-B2ASTM Method
Viscosity, centipoise
35,000 cps
50 cps
850 cps
700 cps
Specific Gravity, gms./cc
 Mix Ratio
 100 : 11
100 : 23
100 : 25
Pot Life, 4 fl. oz. Mass @ 77°F
 40-60 mins
2 hours
5 – 6 hours


When using PT4431 with any of the three Part B hardeners, the material will cure completely at room temperature. The amount of time to cure will depend upon shop temperature, thickness of the casting and the insulating properties of the pattern/mold material. PT4431 Part B is designed for thinner cross section castings or when a fast turnaround time is necessary. PT4431 Part B1 is a good general purpose hardener that works well in thin section casts when fast cure time is not required, as well as thicker castings up to 6 to 8 inches thick. PT4331 Part B2 is for special use in casting large solid mass castings with cross sections up to 12 inches thick, or larger castings with the addition of bulk fillers. Castings made with Part B may be demolded after 18 to 24 hours cure at 77°F. Part B1 castings usually require a full 24 hours cure, and Part B2 castings a minimum of 48 hours at 77°F.

 Quart Kit
Gallon Kit
Pail Kit
Drum Kit
PT4431 Part A
3 lb.
12 lb.
40 lb.
500 lb.
PT4431 Part B
.33 lb.
1.33 lb.
4.4 lb.
PT4431 Part B1
2.8 lb.
2 @ 4.75 lb.
115 lb.
PT4431 Part B2
3 lb.
2 @ 5 lb.
125 lb.

Inasmuch as PTM&W Industries, Inc. has no control over the use to which others may put material, it does not guarantee that the same results as those described herein will be obtained. The above data was obtained under laboratory conditions, and to the best of our knowledge is accurate. This information is presented in good faith to assist the user in determining whether our products are suitable for his application. No warranty or representation, however is intended or made, nor is protection from any law or patent to be inferred, and all patent rights are reserved. Before using, user shall determine the suitability of the product for his intended use, and user assumes all risk and liability whatsoever in connection therewith. In no event with PTM&W Industries, Inc. be liable for incidental or consequential damages. Buyer’s sole and exclusive remedy in such instances shall be limited to replacement of the purchase price.

 PT4431 A/B
PT4431 A/B1
PT4431 A/B2
ASTM Method
Mix Ratio, By Weight
100 : 11
100 : 23
100 : 25
Mixed Viscosity, @77°F, centipoise
5,400 cps
4,700 cps
3,560 cps
Pot Life, 4 fl. oz. Mass, @77°F
40-60 min
2 hours
5-6 hours
Cured Hardness, Shore D
90 Shore D
88 Shore D
88 Shore D
Shrinkage, in./in, Mold #2, Vol: .34 gal
(Mold #3)
Specific Gravity, grams, cc 1.491.471.44D1475
Density,   lb./cu. inch, lb./gallon
.0538, 12.4
.0531, 12.3
.0502, 12.0
Specific Volume, cu. in./lb 18.618.819.2D792
Tensile Strength, psi 9,100 psi
8,750 psi
8,800 psi
Flexural Strength, psi
12,800 psi
11,700 psi
11,800 psi
Compressive Strength, psi
16,400 psi
15,800 psi
15,900 psi


PTM&W epoxy products are made from raw materials carefully chosen to minimize or even eliminate toxic chemicals, and therefore offer the user high performance products with minimum hazard potential when properly used.  Generally, the PTM&W epoxy resins and hardeners will present no handling problems if users exercise care to protect the skin and eyes, and if good ventilation is provided in the work areas.  However, all epoxy resins and hardeners can be irritating to the skin, and prolonged contact may result in sensitization; and breathing of mist or vapors may cause allergenic respiratory reactions, especially in highly sensitive individuals.  As such, avoid contact with eyes and skin, and avoid breathing vapors.  Wear protective rubber apron, clothing, gloves, face shield or other items are required to prevent contact with the skin.  In case of skin contact, immediately wash with soap and water, followed by a rinse of the area with vinegar, and then a further wash with soap and water.  The vinegar will neutralize the hardener and lessen the chances of long term effects.  Use goggles, a face shield, safety glasses or other items as required to prevent contact with the eyes.  If material gets into the eyes, immediately flush with water for at least 15 minutes and call a physician.  Generally, keep the work area as uncluttered and clean as possible, and clean up any minor spills immediately to prevent accidental skin contact at a later time.  Keep tools clean and properly stored.  Dispose of trash and empty containers properly.  Do not use any of these types of products until Material Safety Data Sheets have been read and understood.