Flamemaster CS-3210 Class B  - STM40-107 - Low Density Sealing Compound 

CS 3210 Class B is a two-part, manganese dioxide cured polysulfide sealant specifically developed as a low-density sealing compound for aerospace applications. Its unique formulation allows it to achieve significant weight savings compared to traditional sealants, a critical factor in aircraft design and performance. The "Class B" designation signifies its trowelable consistency, making it ideal for application by spatula or extrusion gun for sealing seams, fasteners, and small access panels. Upon curing at room temperature, CS 3210 Class B forms a tough, flexible, and resilient rubber that provides excellent resistance to aviation fuels, lubricants, and hydraulic fluids, while contributing to overall aircraft weight reduction.

Key Features for Aviation:

• Two-Part System: Consists of a base compound and an accelerator, mixed immediately prior to application.
  
• Polysulfide Chemistry: Provides the fundamental excellent resistance to a wide range of aviation fuels and other aircraft fluids.
  
• Low Density: This is its defining characteristic. It is formulated to be significantly lighter than conventional polysulfide sealants, directly contributing to aircraft weight savings and fuel efficiency.
  
• Manganese Dioxide Cure: A common curing agent for polysulfide sealants, contributing to robust and durable properties.
  
• Class B Consistency: Trowelable, making it easy to apply with a spatula, spreader, or extrusion gun for creating fillets and sealing larger areas.
  
• Excellent Adhesion: Forms strong, durable bonds to typical aircraft substrates, including aluminum, titanium, stainless steel, and composite materials.
  
• Superior Fuel and Fluid Resistance: Highly resistant to aviation jet fuels (JP-4, JP-5, JP-8, Jet A/B), hydraulic fluids (e.g., Skydrol), and engine oils.
  
• Wide Service Temperature Range: Maintains flexibility and sealing properties across the typical operating temperatures of aircraft, from very cold to high heat.
  
• Flexibility and Resilience: Cures to a flexible, rubbery seal that can withstand aircraft vibrations, thermal cycling, and structural movement without cracking or delamination.
  
• Good Work Life (Pot Life): Provides sufficient time for application before curing, depending on the specific "B" class variant (e.g., B-1/2, B-2, B-4, where the number indicates the pot life in hours).

Typical Aviation Applications:

• Sealing Integral Fuel Tanks: Crucial for preventing fuel leaks in the main fuel containment structures (e.g., wings, fuselage sections), where cumulative weight savings from sealant can be substantial.
  
• Weight-Sensitive Structural Sealing: Applied to other structural seams and joints throughout the airframe where a durable, fuel-resistant, yet lightweight seal is required.
  
• Fastener Sealing for Weight Reduction: Used around rivets, bolts, and other fasteners in weight-critical areas to ensure a leak-proof seal while minimizing added mass.
  
• Access Panel Sealing: Applied to seal removable access panels on fuel tanks or other compartments where both sealing integrity and light weight are important.
  
• Filleting and Void Filling: Employed to create smooth fillets around joints and fill small voids within fuel-wetted areas, contributing to both sealing and weight efficiency.
  
• Repair Applications: Used for both production and repair scenarios where the benefits of a low-density sealant are desired.

• All in-stock orders are processed within 1–2 business days (excluding weekends and holidays) after receiving your order confirmation email.
• Orders with a lead time will ship according to the estimated shipping time shown on the product page.
• If we experience a high volume of orders or if an item is backordered, processing times may be slightly delayed. We will notify you promptly via email.

• Returns must be made within a maximum of 3 business days after receiving the product, with prior authorization from Aircraft Shop Supply (Return Material Authorization). Returns without prior notice or written authorization will not be accepted.
• For products with 3 to 6 months of remaining shelf life, claims must be made within the next 2 business days after receipt.
• Returns are not accepted for products with less than 3 months of remaining shelf life.
• Returns are not accepted for products purchased during a low Shelf Life promotion, items sold with discounts, or special orders that must be placed directly with the factory.
• The customer is responsible for the return shipping cost, except in cases where the return is due to an error on the part of Aircraft Shop Supply.
• Refunds will only be issued after the product has been inspected and no damage is found.
• A 25% Restocking Fee will be charged for returns of products in good condition that are either no longer needed or were ordered incorrectly.
• A 35% Restocking Fee will be charged for returns of products with one year or less of remaining shelf life.
• No Restocking Fee will be charged if Aircraft Shop Supply is responsible for incorrectly shipping a product, or if the order is damaged upon leaving the warehouse.
• Hazardous Materials & Dangerous Goods: These items are sold as final and are not eligible for return approval.