Hapcast™ 3738

HAPCAST™ 3738 features:

Black, high density, machinable, rigid epoxy system.
Compatible with a variety of Hapcure curing agents, allowing the system to be customized to the application.
High specific gravity for heavier castings.

Typical Properties*

Viscosity @ 25˚C	9,000 cps
Hardness Shore D	85 - 90
Ultimate Compressive Strength	16,000 - 18,000 psi
Linear Shrinkage inch/inch	.001
Specific Gravity**	2.5
Color	Black
Machinability	Very Good

* Properties may vary, depending on curing agent used. (See chart below)

** Varies depending on curing agent used and mix ratio used

Hapcast Rigid Casting	*Mix Ratio by Weight	Gel Time @ 25˚C	Cure Time	Service Temp. @ ˚F	Description
3738/7	100:7	20-40 min.	16-24 hrs. @ room temp.	260	Iron type Casting System High Density Machinable
3738/30**	100:10	60-90 min.	4-8 hrs. @ room temp. +4-6 hrs. @ 135˚F +4 hrs. @ 195˚F	325
3738/60	100:13	60-120 min.	24-48 hrs. @ room temp.	150
3738/62	100:11	45-60 min.	16-24 hrs. @ room temp.	185

* The lower the ratio, the slower the cure, and the longer the working life. The higher the ratio, the faster the cure, and the shorter the working life. Starting point is the optimum ratio.

** These hardeners must be cured for at least 12 hours at room temperature, and 4-6 hours at 130˚F before de-molding. For models that will not take the final 195˚F temperature, demold only after the 130˚ cycle. Then bring the casting gradually up to the 195˚F curing level, so as not to shock the system. No distortion should occur.