How does dzus fastener work

Some body parts need to be conveniently removable. In some installations, the nose must be removed to service the radiator, and in nearly all installations, the scuttle must be removed for electrical and instrument service. Dzus quarter-turn fasteners are a strong and secure way to mount body parts, and have a long history in aviation and auto racing. And so we offer a "Dzus kit" suitable for mounting one nose or scuttle per kit.

Here's a quick primer on how to use them, using a scuttle as our model. The Dzus system has two main components; a spiral-cam stud often called a "button" and a receptacle containing a wire form spring. The receptacle is mounted on the base structure and the stud goes through a hole in the body panel, with its head on the outside of the panel and its spiral locked into the spring. Dzus fasteners come in a variety of sizes, but the size best suted to our application is the 6.

Our Dzus kit includes four receptacles "plates" , four springs, and four studs "buttons". The receptacle is deeply dimpled for rivets, sufficiently so that countersunk rivets are not required for a flush fit. Leave one receptacle without a spring for the moment. This next step is completely optional, but it drives me crazy when Dzus fasteners are installed crooked.

I want all mine with the slot horizontal when they're locked in place, so I can tell at a glance if I've left one unsecured or failed to give it the full quarter turn. Apparently it doesn't bother the manufacturer, because to get the slot to sit horizontal, the spring has to be cocked a bit in the receptacle, and the receptacles are made with the spring mounting holes level, not the stud. So I trim the bottom of the receptacles to compensate; I eyeball the first one, cut or grind to the line, and mark the other ones to match the first one.

Using the unsprung receptacle as a guide, place it in position on the inside of the body part the scuttle in this demo and trace the center hole onto the part with a felt pen. If you use a dark felt pen black, for example and have a light colored fiberglass part white, for example and a strong source of illumination the sun, for example you can see the traced ring through the part and mark the center of it on the outside of the part.

Doing so may make drilling easier. Test fit the parts. Push the stud into the hole in the scuttle from the outside, push the retainer washer not visible here onto the stud from the inside, fit the receptacle over the stud with the spiral-cam portion of the stud fitting onto the spring portion of the receptacle, and give the stud a quarter turn, using a large screwdriver, small coin, or even an authentic Dzus tool.

This will hold the parts tightly together. Turn them so the base of the receptacle is properly positioned to weld to the chassis, and do the same with the other three sets of parts. This is your opportunity to get the fit just right. The stepped-spring can be flipped over and used with thinner material with a shorter-reach fastener. Take your measurement by adding the thickness of the material to the installed spring height.

The installed height of a flat spring is approximately. Read on for additional details on these springs, mounting plates, and how to properly measure for your application. As noted above, you will find quarter-turn fastener springs in both flat and stepped designs, with the stepped design providing the freedom of installing with the step facing up or down to accommodate your material thicknesses.

Matter of fact, all quarter-turn springs we offer mount as such. Spring mounting plates are commonly used to fasten a panel onto tubing or a chassis Example: Most of the body panels of a Sprint car are fastened to the chassis using spring plates. For street cars spring mount plates are often used in conjunction with self-ejecting quarter-turn fasteners for things like fiberglass hoods, hood scoops, and interior access panels. Lightweight and scalloped versions are available to save weight in applications where every ounce counts.

A scalloped version is shown here to the left. Length and material thickness calculations are critical to ensuring your quarter-turn fastener has the proper reach and grip to allow full engagement with the spring to the fastener. The quarter-turn measuring guide illustration shown here and linked for a larger version will aid you in obtaining the proper quarter-turn fasteners, springs, and spring plates for your project.

Some installations will have several thickness of material stacked up so be sure to compensate for all layers between the spring and the head of the fastener. Letter B is the spring height. Two different spring heights are available to help compensate for different material thickness being fastened. Letter C is the quarter turn fastener length.

This length needs to be equal to or very close to the sum of A and B. Example: Material thickness A of. Installation tip — If your quarter turn fastener is just a bit too long and does not tightly hold the material together you can adjust this by bending the spring slightly. Use a large flat blade screwdriver to push on the spring through the fastener hole.

If access from the back side is available then pliers can be used to pull on the spring. You simply slide this guy over the spring, hold your panel in place and lightly tap with a rubber hammer. Now you have a mark to drill out for your fastener. The two-piece design is zinc plated and transfers a precise. The S6 spring default size is the S which gives a 0. The grip length and clearance can be fine-tuned with an adjuster tool if the correct clamping depth is not achievable.

The Pitking Products brand offers a black fastener that is interchangeable with the above Dzus fasteners and are ideal for classic applications etc. Black rivets to suit are available to complete the look. Reinforcing backplates are available for all the above if use is intended on very lightweight panels.

These spread the load and are especially useful on fibreglass, and there are mounting brackets for the springs available which can save a lot of fabrication work. Dzus also offer the Panex range that works on the same design principle but does not have the top diamond shape encapsulated plate and instead sits directly on the panel to be secured.

To calculate the length of stud required, add together the thicknesses of the panels being fastened, then add 7mm for the receptacle. Round up or down to the nearest mm to obtain the length required. The head of the Panex can be slotted for a screwdriver or a D ring for manual opening.

The head is retained by a spring washer fitted on the reverse side of the panel, these are available in steel or plastic. The receptacle can be either rivet type for mid panel use or slide on for the edge of panels. Camloc offers a range of quarter-turn fasteners very similar to the above Dzus Panex. The most popular type is the series that are available as a slot head or cross head. The 15F series is a push-button version that needs no tools to operate and is simply operated by a finger or thumb.

All variants have a round flange to fit against the outside panel and are secured in place by a retainer washer. The receptacle on the series is offered as a rivet on or screw on type and is held in place by a locknut. The 15F receptacles are screw on type only. The fasteners are selected by the combined panel thickness exactly as choosing a Dzus fastener.

These start at 0. The 15F series is only available to suit 0. Pip Pins are a quick release fastener released by a push button. The top panel is held in place by the shoulder on the Pip Pin and the lower part is held in a tube that matches the outer diameter of the pin shank. The Pip Pin has two spring-loaded balls near the end of the pin.

These protrude once the button is released and hold the pin in place by protruding from the end of the tube the pin sits in. The thickness of the panel and the depth of the locating tube combine to give the grip length required. A typical application would be to replace bonnet hinges with a pip pin to allow quick removal, single seaters sometimes use them on the anti-roll bar stay to allow easy engine access.

The Allstar brand offers a variation of the Pip Pin that has a T-handle that works in the same manner. This is easier to remove but the head is bulkier. Speciality Fasteners Detent Ring Pins are similar to Pip Pins but have no shoulder, just the ring to bear on the top panel. The spring-loaded balls allow quick and easy fitting and removal. The pin fits inside a tube in the same manner as a Pip Pin. The grip length is measured from the base of the ring to the ball retainers.

The Dzus slide latch is intended to allow a panel to be quickly removed from the lower panel by a simple movement of the slide. The plate fits to the outer panel and is rivetted in place. The bush is fixed to the lower panel.

The outer panel is secured by dropping the fastener over the bush and then sliding the tab over the bush. A typical application would be to hold a lamp pod or scoop on a bonnet. An over centre latch will pull two panels together and will lock in place by the tension caused by the offset of the latch. These can be adjustable for reach or fixed and sometimes have a positive secondary lock for extra security or alternatively a loop for padlock or lockwire.

A typical fitment would be to hold a boot lid down against a rear panel. Aerocatch offers a recessed version that drastically reduces drag as pictured below:. Spring hooks hold two panels together in a similar manner to overcentre clips but rely on the spring tension rather than the over centre action.

Often known as boot springs as holding the boot lid or tailgate closed is the most common use.