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Naftoseal MC-780 Class C-2 Fuel Tank & Fuselage Sealant

Silmid P/N: VAR0000992
From £54.59 (excl VAT) £65.51 (Inc VAT)

Naftoseal MC-780 Class C is a two-component, manganese-dioxide cured polysulfide polymer system with reduced density providing excellent fuel tank and fuselage seals. The C-2 denotes that this product has a 2 hour application time.

Product Properties

Chemetall Naftoseal®
Sealant Class
Class C
Application Time
2 Hours


AIMS 04-05-001 | AIMS 04-05-012 | AIMS 04-05-014 | AIMS 04-05-015
Miscellaneous Specs
MEP 09-084

Please Note: Specifications and approvals are subject to change at any time. Users should always consult their AMM or the OEM when selecting products to ensure items have the release needed. Only specifications listed on the order confirmation will be certified on the Silmid CofC.

Product Information

It is designed for interfay surface sealing and wet riveting of fuselage components and has outstanding resistance to aviation gasoline and jet fuel, as well as resistance to the chemicals and petroleum products used in the aircraft industry.

Additionally, it was developed for a service temperature between -55 °C (-67 °F) to +130 °C (+ 266 °F) and withstand a shortterm temperature of +182 °C (+360 °F).

Naftoseal MC-780 Class C maintains its flexibility and bond strength on most metal substrates like aluminium, stainless steel, steel, titanium, composite and many coatings under extremes of temperature, weathering and stress.

Naftoseal MC-780 Class C combines low viscosity, for ease of mixing, with a high thixotropy giving good application characteristics. It can be effectively applied by extrusion, by injection gun, or by using a roller coating technique. The low viscosity means that it is easily squeezed from interfaying surfaces during the assembly process and it has a unique self-filleting characteristic.

The curing time may be reduced considerably by increasing the temperature (up to 60°C or 140°F max).

Surface Preparation:

To obtain good adhesion, clean surfaces with appropriate cleaners (e.g. Chemetall's Ardrox products like Ardrox 5529 or Ardrox 5575) to remove dirt, grease and processing oils just prior to sealant application. Use lint-free rags or paper towels that are free of oil. Always pour cleaner on the cloth to avoid contamination of the cleaner supply. Clean one small area at a time, quickly wiping it dry before the cleaner's solvent evaporates to prevent redeposition of oil, wax or other contaminants. PUR and EP topcoats as well as composite components should be pre-treated by the Naftoseal MC-115 Adhesion Promoter.

Shipping information

Orders over £100 placed online will now qualify for FREE UK Mainland delivery*

Orders under £100 placed online for UK Mainland delivery is £12.00*

**Orders requiring Pre 10.00am Next Day delivery has also been lowered from £35.00 to £30.00, orders placed through the office will incur additional charges.** 

International delivery (door to door delivery) is available for selected countries worldwide. Shipping will be automatically calculated based on the weight, location and hazardous nature of the goods. Customers can also choose ex works to arrange their own collection.

Please refer to our delivery page for more information.