New Products


Mechanically locked 95 KSI blind bolt for primary structure

MLAThe new Mechani-Lok is another first from Monogram Aerospace Fasteners. This MLA series blind bolt is an addition to Monogram’s growing suite of high strength blind fasteners for primary structure. The Mechani-Lok (or MLA) is a two piece, 95 KSI shear strength bolt designed for installation in both laminated composites and high-strength metal alloys. The A-286 cres body and 6-6-2 titanium alloy core bolt are mechanically locked together during assembly at the factory and cannot separate in service.

Upon installation the tail of the body forms a large blind side upset against the tail side panel surface to mechanically lock the assembly to the structure. Preload is retained because the core bolt is set by torsion, avoiding the recoil of pull-type blind bolts. The installed flushness of +0.000”/-0.010” eliminates the need for post-installation shaving and filling. Installation is assisted by means of a disposable drive nut, eliminating the operator or worn tooling as a source of installation errors.

  • Mechanically Locked → acceptable for installation forward of engine air inlets
  • 95 KSI shear strength
  • Suitable replacement for pin and collar systems
  • High preload retention →  greater than 50% of tensile strength
  • Absolutely flush break-off → no shaving or filling
  • Disposable drive nut facilitates installation and eliminates recess “cam-outs”
  • Compatible with robotic installation

The Mechani-Lok was initially designed to incorporate the advantage of a mechanical lock with the advantages of high preload retention, large blind upset and ease of installation already present in Monogram’s blind fastening line-up. These characteristics, in addition to the Mechani-Lok’s light weight and shallow blind side protrusion in comparison to other structural fasteners, make the MLA ideally suited to the new A350, A380, and B787 platforms as well as potential military applications. The suitability for composites, aerodynamic flushness and easy adaptation to robotic installation make this fastener an ideal replacement for current pull-type blind bolts and pin & collar fasteners such as Lockbolts, Hi-Lites® and Eddie-Bolts®.

Contact MAF for additional product information

(Hi-Lite is a registered trademark of Hi-Shear Corporation. Eddie-Bolt is a registered trademark of Alcoa Fastening Systems)