For many types of open mold casting, both a male and female mold are required. Examples are vanity bowls, bathtubs and some accessory products. Female molds are the mold shape that forms the underside or backside of a cast cultured marble or solid surface product. When properly positioned with the male mold, it creates the cavity that is filled by matrix to form the cast part.

Gruber Systems has developed a multitude of different kinds of female options to satisfy the diverse needs of its customers. However, because there is such a diversity of needs and production methods, one type of female hat may work better than another, for different customers, including:

• Female Molds - reused indefinitely if taken proper care of. There are four sub-categories of females within this group (see below).
  
• Permanent Hats - this is a "disposable" type of female, in that it is a lightweight, low-cost plastic "hat" that is used in place of a true female mold and cast into place. It is not removed during demolding.
  
• Reusable Hats - reused many times like a female mold, but not nearly as durable

Female Molds

• Most durable, reusable and best quality
• Two types - floating fiberglass female, and full fiberglass females
  

Gruber Systems has developed a multitude of different kinds of female hats to satisfy the diverse needs of its customers. However, because there is such a diversity of needs and production methods, one type of female mold (or "hat") may work better than another, for different customers.

Female mold options can generally be categorized as a female (shown immediately below), but there are alternatives that you should consider before purchasing a female mold.

Floating Fiberglass Female	Full Fiberglass Females (3 varieties)
Floating Fiberglass Female (FFF)	Full Fiberglass Female-Flange Out (FFO)	Lightweight Fiberglass Female (FFL)	Ultralight Fiberglass Female (ULFF)

Floating Fiberglass Female (FFF)

Full Cover Fiberglass Female

A Full Cover Fiberglass Female mold offers all the advantages of strength, durability and reusability as the Floating Fiberglass Female (FFF) above, but with two additional advantages.

1. The overall size of the female matches the overall size of the modular vanity mold with which it is used
2. It has a heavy steel frame that provides not only rigid support to the female but also a firm surface for clamping the female to the male mold.

Full Fiberglass Female-Flange Out (FFO) The Full Fiberglass Female-Flange Out (FFO) yields a finished part with a nominal 3/4" (l.9 cm) thickness both in the deck and bowl sides. Available for most standard modular mold lengths up to 49" (124.5 cm).
Lightweight Fiberglass Female (FFL) The Lightweight Fiberglass Female (FFL) yields a part with a 1/2" (1.3 cm) thickness over most of the deck area and a 3/4" (1.9 cm) thick bowl. Available for most standard modular mold lengths up to 49" (124.5 cm).
Ultralight Fiberglass Female (ULFF) The Ultralight Fiberglass Female (ULFF) yields a part that is not only 1/2" (1.3 cm) thick over most of the deck area, but also creates a 1/2" (1.3 cm) thick bowl. Available in standard lengths up to 37" (94 cm) for many, but not all, modular molds.

Note: Most females must be ordered separately in addition to the male mold. Refer to the Mold product section, and the various female mold and hat options will be listed with each mold.

Lower-Cost Plastic Female "Hat" options

Gruber also produces "hats - which are not as durable as a female mold shown above, but offer unique advantages:

Two types - Permanent Hats, and Reusable Hats

Permanent Hats

• Clear or White, and with or without Overflow

Permanent Hats become a permanent part of the marble product, providing a finished underside which requires very little, if any, additional finishing.  The hat is set in place on the un-gelled first cast immediately following vibration.  Gently depress the step-down part of the flange into the matrix just enough too barely cover it.  Because they conceal the underside of the bowl, any color of matrix can be used for the backpour. When the first cast of matrix has gelled and cooled, the second cast (backpour) can be made.  The permanent hats are available in a white or clear plastic, and with a choice of including an overflow, or no overflow. Gruber part numbers beginning with PH are permanent hats.

Reusable Hats

• With or without Overflow
• Trimmed (RH) or Untrimmed Hat (UNTRM-RH)
• Reusable Funnel accessory available - don't spill matrix!
  

Fabricated of high-density polyethylene, a reusable hat will provide many trouble free castings if reasonable care is exercised in its use and storage.  A reusable hat is applied to the mold after the initial pour of the matrix has been vibrated.  It is placed over the bowl and the rim of the hat is gently pressed into the un-gelled matrix.  A generous 2” flange is provided around the perimeter of the hat to allow for maximum adhesion of the hat to the matrix.  Reusable hats are also available with an “untrimmed” flange around the perimeter.

To order a Reusable Hat, place the letters "RH" in front of the series designation of the bowl with which the hat will be used. For example: If ordering a Reusable Hat for a series "S" bowl, the order would read, "RH-S."

Reusable Funnels are a convenient add-on to your Reusable Hat. They are available in Round, oval and square to match your Reusable Hat

Which type of female "hat" is best for your needs - a Permanent Hat or a Reusable Hat?

Fiberglass Female Molds are the most dimensionally stable, and result in a uniform wall thickness. Reusable Polyethylene Female Hats are still preferred by some customers, even though they are more difficult to work with and produce a less uniform part. Permanent Female Hats are very popular because of their ease of use. We suggest that you try the different types of female hats and select the one(s) that best suit(s) your own needs and requirements.