DZUS Fasteners

When I became interested in constructing a simulator, I heard knowledgeable people stating DZUS this or that - I had no idea what these individuals were referring to, let along how to pronounce the word.

LEFT:  A selection of real B737 DZUS fasteners beside a DZUS rail.

Dzus (pronounced Zooss) is a proprietary name for a type of quarter-turn fastener often used to secure skin panels on aircraft.

It was invented and patented by a native Ukrainian William Dzus (Volodymyr Dzhus) in the early 1930s. Quarter-turn fasteners are used to secure panels in equipment, airplanes, motorcycles, and racing cars that must be removed often and/or quickly.  These fasteners are notable in that they are of an "over-centred" design, requiring positive sustained torque to unfasten. Thus, any minor disturbance to the fastener will correct itself rather than proceed to further loosening as it would in threaded fasteners.

Real DZUS Fasteners

Finding individual real DZUS fasteners can be difficult as they are mostly attached to avionics panels, and the vendor wants to keep them with the panel.  If you search long enough, eventually you will find an aviation scrap yard that has them available as separate units.  I recently saw several selling on e-bay quite cheaply.  I have a small collection of grey, black and bare metal coloured fasteners in varying condtion, obtained from a scrapped Boeing B737 (I bought them in a 30 piece lot).  The fasteners are needed to lock down any avionics panels (real or FS) to the DZUS rails of the real B737 avionics bay (centre pedestal) I’m using.   

Reproduction DZUS Fasteners

If you’re using a real bay/centre pedestal with a DZUS rail, then FS avionics such as those produced by CP Flight or Simso will not be able to secure to the rail easily.  You will need to enlarge the circular hole along the edge of the module to allow the real DZUS fasteners to fit easily and correctly.  Be very careful that you don’t damage the edge of the module when you enlarge the circular hole.  I used a titanium drill bit and carefully secured the FS module in a vice on a workshop bench (wrapped carefully to avoid the vice jaws damaging the module)

If you have replicated your bay from MDF or wood and want to use something more realistic than “boring” screws to attach your modules, you can purchase aftermarket “look alike’ DZUS screws.  Basically these are wood screws with DZUS style heads on them.  Two suppliers of DZUS screws are SISMO Soluciones and GLB Flight Products.  I’ve used these on my earlier generic slight deck and they work very well and look just like the real ones…

Comments

[Richard Long]

Hi,

I understand the length-wise spacing of the DZUS fasteners is 0.375 in. Can you tell me what the width-wise separation is of the fasteners? I understand this to be something of the order of ~143 mm???

Thanks

Richard

[FLAPS 2 APPROACH]

Hi Richard:

I sent an e-mail to you. Distance between each DZUS is 14.5 cm (outside edge to outside edge of fastener). The length between the fasteners does not alter, however the width does as this depends on the module in question. Hope I have answered your question. Cheers, F2A