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Naftoseal MC-780 Class B-1/2 Fuel Tank & Fuselage Sealant

Silmid P/N: VAR0001003
From £60.63 (excl VAT) £72.76 (Inc VAT)

Naftoseal MC-780 Class B is a two-component, manganese-dioxide cured polysulfide polymer system with low density providing excellent fuel tank and fuselage seals. The B-1/2 denotes that this product has a 1/2 hour application time.

Data Sheets

Download the Naftoseal MC-780 Class B-1/2 Fuel Tank & Fuselage Sealant technical data sheet (TDS) and the Naftoseal MC-780 Class B-1/2 Fuel Tank & Fuselage Sealant safety data sheet (SDS) from Silmid today. Once you have logged in or signed up, select the product size you are interested in and the datasheet will be visible for download if one is available.

Product Properties

Sealant Class
Class B
Application Time
30 Minutes


AIMS 04-05-001 | AIMS 04-05-012 | AIMS 04-05-014 | AIMS 04-05-015
Miscellaneous Specs
BAMS 552-008 | BAMS 552-009 | 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 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 B 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. The mixed compound is a thixotropic paste easily applied by extrusion, injection gun or spatula and has excellent tooling properties.

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

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