MASTER® Dyna-Cast, being a very versatile product, has found many uses other than mass casting. One such technique is the use of Dyna-Cast with Aluminum Grain.

There are two basic ways to build a tool using this technique: solid cast or conforming cast.

Both techniques begin the same way. The pattern or mold must, of course, be prepared and released with adequate parting agents. When this has been done, a thin coat of Dyna-Cast must be applied to mold or pattern surface. This coating or "shell" should be no less than 1/32" thick (See "Shelling with Dyna-Cast®"). Immediately upon completion of this step, mix another very small amount of Dyna-Cast and brush onto previously applied Dyna-Cast. This coating should not add thickness--it is a bonding coat to insure adhesion between the face coating and the grain structure which is applied immediately after the second coat.

The grain structure is made by mixing a batch of Dyna-Cast and adding medium size aluminum grain to this mix until saturation occurs.

This ratio will generally be about 100 parts Dyna-Cast to 120 parts aluminum grain by weight or 50/50 by volume.It's important that the grain content be as high as possible.

For solid casting (small or shallow tools) simply press grain mixture into second coat of Dyna-Cast and tamp lightly to assure adhesion. If small pockets or cavities exist, fill these first before dumping entire batch. To make conforming casts, "follow ribs" may need to be cut. Follow ribs are made by cutting wood or template stock to shape of surface, leaving ½" to 1" space from rib to surface for wall thickness.

These ribs do not become part of the job, but will give you an indication of thickness of grain as you apply. Dyna-Cast, when mixed with the right amount of aluminum grain, is a dough-like material.

It can be "worked" for 5-10 minutes with hands to shape or conform it to surface. This dough material will sag, but keep working until it does what you want. Be sure to cover entire mold surface with grain mixture to insure bonding, then proceed to build thickness.