Custom Gaskets

Manufacturing custom gaskets and fast-turn custom gasket production of is Stockwell Elastomerics’ core competence. Using customer designs, Stockwell Elastomerics can mold, die cut, kiss-cut, waterjet, and slit parts from a wide variety of stock materials.

Custom Gasket Materials

Stockwell Elastomerics inventories a wide range of engineered elastomeric materials for producing custom gaskets. Gasket material selection is as important as the actual gasket design. Materials should address environmental conditions like wind driven rain, pressure washing, freezing temperatures, extreme heat and general life expectancy. Below is a list of common gasketing materials inventoried by Stockwell Elastomerics that can be cut into custom geometries.

• Silicone
  • Closed Cell Silicone Sponge
  • Closed Cell Silicone Foam
  • Open Cell Silicone Foam
  • Solid Silicone ( 10 durometer to 70 durometer Shore A)
  • Fluorosilicone (sponge and solids)
• PORON® Urethane Foam
  • 4790-92, Extra Soft Foam
  • 4701-30, Very Soft Foam
  • 4701-40, Soft Foam
  • 4701-41, Soft Foam with Enhanced Sealability
  • 4701-50, Firm
  • 4701-60, Extra Firm
• Electrically Conductive Rubber
  • Nickel Graphite Filled Silicone
  • Silver Plated Aluminum Filled Silicone
  • Silver Plated Aluminum Filled Fluorosilicone
  • Carbon Filled Silicone
  • Carbon Filled Neoprene
• Thermally Conductive Rubber
  • Ceramic Filled Silicone Coated Fabric
  • Ceramic Filled Silicone Sponge
  • Ceramic Filled Solid Silicone
  • Ceramic Filled Gap Fillers
• Closed Cell Rubber (organic)
  • Neoprene
  • Blended Neoprene
  • EPDM Sponge
  • Epichlorohydrin (ECH)

Click here for specific product datasheets for all of the above materials.

Custom Gasket Types and Manufacturing Processes

Stockwell Elastomerics has extensive gasket manufacturing experience, with in-house molding, waterjet cutting, laminating and die cutting and a comprehensive material inventory. Stockwell Elastomerics is uniquely capable of manufacturing custom gaskets with a core competence in custom silicone gaskets. Stockwell Elastomerics also offers pressure sensitive adhesive lamination on most materials. Adhesive backings also allow for custom kiss-cutting which can reduce assembly time.

The following types of custom gaskets can be manufactured:

Waterjet Cut Gaskets

Four in-house waterjet cutters allow Stockwell Elastomerics to manufacture low and mid-volume production parts without tooling. Tool-less gasket cutting allows for fast, low cost design iterations. If a CAD file (3D .stp or 2D .dxf) is provided, Stockwell Elastomerics does not charge a setup fee for waterjet cut gaskets.

Waterjet cutting allows for fast turn, rapid gasket manufacturing and tool-less prototyping of flat cut gaskets. It often happens that, after the short lead time made possible by water jet cutting gets a customer out of a “jam”, gasket designs are then tooled up for die cutting or molding. Short lead time gaskets are commonly produced at Stockwell Elastomerics; low volume gaskets can be manufactured in days when stock materials are used and a CAD file is provided.

Die Cut Gaskets

Gaskets and pads can be cut in a variety of ways. The most common die type for elastomer cutting is a steel rule die. Steel rule dies are manufactured by laser cutting a custom geometry into engineered wood; steel ruling (steel strip with a bladed edge) is then pressed through the laser cut slots. Steel rule dies are relatively inexpensive and fast to make. It’s important to note that there are some restraints on radii and clearances with all dies. Higher precision gaskets may require an alternate cutting process such as waterjet cutting or molding.

Stockwell Elastomerics is equipped to handle low to mid-volume runs of die cut gaskets using high speed Preco semi-automatic die cutting presses, auto-feed CNC large bed presses or a variety of beam presses.

Flash Cut Gaskets

Using die-less, automated, digital knife cutting systems that can cut most silicone elastomer materials at high speeds, Stockwell Elastomerics fabricates flash cut gaskets and pads. This is especially useful for quick turn prototyping and rapid production.

Molded Gaskets

Stockwell Elastomerics is a custom silicone molder, with both liquid injection molding and compression molding capabilities. The bulk of molded silicone rubber parts are manufactured to customer 3D models using the injection molding process. LSR injection molding allows for a wide range of durometers (10 – 70 Shore A) and has much shorter cycle times as compared to compression molding.

Compression molding is required for specialty materials such as electrically conductive silicone and fluorosilicone. The gum based silicones often have unique properties or specifications that require the longer cycle times of compression molding.

Custom Silicone Sheets

With in-house molding, stocked silicone compounds and waterjet cutting, Stockwell Elastomerics is able to mold custom silicone sheets to meet some “granular” customer requirements. Custom molded rubber sheets are shipped for customer cutting, or quite often Stockwell Elastomerics does waterjet cutting to produce custom geometries per customer supplied CAD files.

As with most silicone rubber sheets and roll materials, Stockwell Elastomerics offers peel and stick adhesive backings. Adhesive range from very low tack to very high bond (VHB), allowing for the proper adhesive for an application.

Gasket Tape

Stockwell Elastomerics manufactures “semi-standard” gasket tape as well as custom combinations of materials and sizes. Stockwell Elastomerics semi-standard gasket tapes are made from silicone sponge and silicone foam, pre-laminated with standard adhesive backings in dedicated roll lengths. Stockwell Elastomerics cuts these master logs to customer specified roll widths.

Custom gasket tapes are manufactured regularly, made from customer specified gasket materials per Stockwell Elastomerics’ material offerings. They are combined with 3M or Adchem pressure sensitive adhesives. Custom lengths and roll widths can be specified. Custom gasket tapes require full master roll consumption and orders to be in increments of full master rolls. Example: 1″ wide rolls are required from a 34″ wide master log, order quantities to be in increments (34) 1″ rolls.

Custom Gasket Geometries

Stockwell Elastomerics fabricates custom gaskets to customer supplied drawings. Popular gasket geometries are rectangular gaskets, ID OD gaskets and “window” gaskets. Rectangular gaskets and window gaskets are quite often the same – a rectangular OD with a smaller matching ID. These gaskets are often used on the enclosure or seal the window of a LCD display.

ID OD gaskets are often referred to as washers; usually the material or size differentiates the differences. ID OD gaskets are commonly used for flanges or electronic connectors. Connector gaskets usually are made from soft foams or sponges to reduce the clamp force required to get a seal.

Stockwell Elastomerics manufactures complex and basic gasket shapes using waterjet cutting, molding or die cutting. Each process has its benefits and limitations, and Stockwell Elastomerics can help with selecting the proper process based material, quantity needed and part complexity.