Ultimate Guide to Blind Rivets

Huck Aerobolt - The Ultimate Guide to Blind Rivets

What is a rivet?

Rivets are a popular fastener used to join two or more pieces of material. Essentially a rivet is composed of two components, a metal tube (body) & pin (mandrel). The pin is normally longer than the tube and designed to be pulled up through the tube whilst enlarging it in the process.

This results in the expanded tube clamping the material between the two ends of the tube. There are numerous rivet types for virtually any application; from connecting your home’s guttering through to the cars we drive and the planes we fly. In fact, it is almost impossible to imagine today's world without rivets. See image on the right for the anatomy of a typical rivet.

Typical Standard/Pop Rivet

 

What are the advantages of rivets?

Permanent & superior fastener option compared to most other fixings, key advantages include:

  • One side assembly for fast installations, as access to the rear is not required
  • Highly resilient, forming a mechanically activated permanent joining solution.
  • Easy to use air, cordless, and manual rivet tools that require minimal effort and training.
  • Design flexibility, wide range of types and materials to suit most applications.
  • Easy inspection and maintenance, no expensive equipment for quality control.

    What are the main rivet types?

    Here we list the common types of blind rivet sub-categories plus some specialised industrial strength structural rivets. Your selection criteria should be based on the application connection you believe is required, whether your job involves installing metal roofing, guttering or building a truck trailer. There are numerous rivet labels or names for the same rivet type and in this blog we have incorporated the different labels into the title.   

    Rivets Standard.

    Open End Rivet. (Rivets, Pop Rivet or Blind Rivets).

    Commonly referred to as "rivets" open end rivets are a low-cost fastener option that is available in a range of materials, including different combinations of metals. The most common ones include: steel & aluminum, all steel, all aluminum, stainless & steel, all stainless, nickel & copper. A popular choice with many of our building construction customers.

    Closed End Rivets. (Sealed Rivets).

    Closed end rivets are like open ended pop rivets however they have a cup shaped end configuration that eliminates water ingress from within the body of the rivet, but not between the outside of the body and the material. Many customers purchase sealed rivets believing they are waterproof, unfortunately this perception is not 100% correct.

    Multi-Grip Rivets.

    Multi-Grip rivets are a strong & highly flexible option due to their extended material grip range. The multi-grip rivet is our strongest standard rivet choice, for many customers this rivet helps reduce stock options as one multi-grip rivet replaces a few different size open end rivets. We find this assists to reduce cost and minimise operator errors with many of our steel fabrication customers.

    Tri-Fold Rivet.

    Aluminum tri-fold rivets or split rivets are designed for the assembly of lightweight materials such as fiberglass, plastics, thin steel sheeting & composite material. This rivet forms a propeller shape anchor connection on the blind side of the material without damaging it. Tri-folding split rivets are installed with the same type of rivet gun that install all other standard type rivets.

    Peel Rivets.

    Peel rivets are also ideal for the joining of softer material such as timber, plastic, rubber, fibreglass, and laminates. Upon installation, the rivet body splits into petals that bends outwards, like peeling a banana. The petals bend out and contact the blind side of the material, creating a large anchor head.

    Groove Rivets.

    Groove Rivets are designed to be installed within a hole as they infuse themselves into the material, making them ideal for soft materials such as timber, plastics & other fibrous material. When set correctly, the annular rings around the body will expand into the surrounding material.

    Structural Rivets. 

    Huck Rivet Magna-Lok. (Monobolt®).

    Huck Magna-Lok® is a versatile structural rivet that is ideal for multiple material grip ranges. This rivet has Huck’s unique internal locking mechanism that provides a high resistance to vibration & moisture. Fast and easy to install using conventional Huck brand gun or a structural rivet gun. Aerobolt is Australia's number #1 Huck distributor with the complete range of structural rivets and structural rivet tools. 

    Allok Rivets. (High Strength Rivets, Orlock Rivets).

    Allok®, High Strength Rivets, and other bulb forming rivets feature a double-locking system that secures the material on both sides of the panel for great strength, providing a vibration and weather resistant joint. It has a non-protruding blind side bulb that spreads the load, whilst avoiding pull-through. Easy to install via a Huck gun & other structural rivet tools as a standard rivet gun is not built to install structural rivets. 

    Bulb-Tite Rivets (Huck-Tite, Tri-Bulb).

    These rivet differs from other types due to their slot body that creates a propeller shape blind–side anchor that combines with a washer to provide a weatherproof joint. Bulb-Tite®, Huck-Tite, and many other tri-folding split body rivet spreads their clamping force through the anchor blades whilst providing excellent pull through resistance, making them an ideal choice for lightweight panel applications, humid conditions, or where water might be an issue. 

    Self-piercing rivets.

    This is another category of rivet, a self-pierce rivet joins two or more layers of material by piercing the top layer of material and then flaring out at the bottom layer, forming a mechanical interlock. As the name suggests predrill holes are not required, allowing for a rapid, strong, fastening solution that would suit numerous applications. This item is not on our site, however we do stock them.   

    Self-Piercing Rivet

    What is the difference between pop rivet and blind rivet?

    Many customers ask this question and the short answer is there is no difference. These are two different rivet labels for the same rivet type, a blind rivet means you do not need access to the other side of the material, or you can't see the other side of the material whilst installing. Also known as pop rivets because this is the name of the original rivet company-Pop® and rivets make a popping sound upon installation.  

    How do I select the right rivet?

    Rivet selection is easy, you will need to consider material, size, and material grip range before making a final choice.  

    Materials.

    Ensure the rivet material is compatible with the material being joined to avoid galvanic corrosion. As a rule, avoid using aluminium and stainless steel together, we recommend keeping the metal material like for like for maximum life. Stainless with stainless, aluminium with aluminium, etc.

    When reviewing material, you will also need to consider environmental factors, such as extreme temperatures or salt sprays. See the table below as a general guide.

    Rivet Material Compatibility

    Diameters & Hole Size.

    The size of the rivet diameter & the drill hole size is critical for success. If the rivets diameter is too small for its hole, then the gap may cause installation failure. Referring to the hole diameters before drilling is an easy way to avoid issues later.

    Refer to the table below covering diameters and corresponding hole sizes.

    Diameter Codes & Grip Ranges

    Material Grip Range.

    The material grip range refers to the material thickness or the depth the rivet can be effectively installed. For example, if two 1.5 mm plates/items need to be riveted, a blind rivet with a material grip range between 2- 5 mm is required. Best practice dictates that the middle grip range of a rivet should be used and not the minimum/maximum sizes. This assists in achieving correct shear and tensile strength whilst ensuring the longevity of the rivet. Please note that the grip range is not the length of the rivet as many people mistakenly believe the length is the amount of material the rivet will pull up.

    Listed below we have a table listing standard blind rivet material grip ranges and their corresponding grip code.  

    Rivet Grip Codes & Ranges

    Head type

    The rivet head type assists in holding the material together and enhancing its appearances. Dome heads sit proudly above the material, whilst the large flange or truss head is a shallower broader head profile & well suited for thin or soft material items like rubber or fibreglass. The countersunk option provides a flush neat finish subject to countersinking a hole first, allowing for the head to sit level with the surrounding material. The image below covers the typical head types plus a few specialised rivet type profiles.

    Rivet Types

    Frequently Asked Rivet Questions.

    How do I order rivets?

    You'll need to know the body & pin/mandrel material, head type, diameter and grip range before you order. Using the codes for each of these variables, you can derive a product code such as:

    Rivet Code Identification System

    In the above product code example (in the red box), beginning from left to right we have:

    A = Aluminium Body. Other options include (S = Steel, SS = Stainless)
    B = Button / Dome Head. Or you can select (T/LF = Truss/Large Flange, C = Countersunk) 
    6 = 4.8mm (3/16") Body Diameter. The other options are (4 = 3.2mm (1/8", 5 = 4.0mm (5/32"), 8 = 6.4mm )1/4").
    6 = 7.9-9.5mm Material Grip Range. See above for more choices (See grip codes number table in previous section)
    S = Steel Pin/Mandrel. The other options are (SS = Stainless, A = Aluminium).

    How do I remove a rivet?

    Rivet removal is straight forward with the right tools. This requires the destruction of the rivet, and the best method is to drill it. You will need, a drill, drill bit, long nose pliers, & safety accessories such as glasses and gloves.

    Steps: Use your safety glass & gloves before starting the drilling process. Place the drill bit against the rivets’ center pin and drill through the body at a low but steady speed. Once drilling is completed, pull the rivet off with your long nose pliers. How easy was that!  

    How do I install rivets?

    To install a rivet is simple with practice, pre drilling of holes is required. Load rivet’s pin tail section into rivet gun. Insert rivets body into hole and activate gun. Upon activation the head of the rivet is pushed against the outer surface of the tool, whilst the tool pulls up the central pin. As a result, the bottom portion of the rivet compresses, and expands on the blind side. This expansion increases until it reaches approximately one and a half times the size of the original diameter. Resulting in a larger surface in which the two materials are effectively fastened together.

    How does a rivet work?

    How rivets work is ingenious. Essentially a rivet is composed of two components, a metal tube (body) & pin (mandrel). The pin is normally longer than the tube and designed to be pulled up through the tube whilst enlarging it in the process. This results in the expanded tube clamping the material between the two ends of the tube. See the image below to better understand how a rivet works.

    How Rivets Work

     

    Which is the best rivet gun?

    Selecting the correct rivet gun depends on several factors that relate to your specific requirements, rivet gun section is covered in the blog; Ultimate Guide to Rivet Guns.

    Which is the strongest rivet? 

    Structural rivets are the strongest rivets on the market and Aerobolt has the complete Huck Rivet range including the original multi-grip rivet "Magna-Lok", the Huck Rivet "Magna-Bulb" with its superior strength and the hybrid of the two "Hucklok Rivet"One of the strongest structural rivet option is the the Huck Rivet "Magna-Bulb" refer to the table below to compare a range of structural rivet's lab results.

    STRUCTURAL RIVET TYPE KEY METRICS FOR STEEL 6.4MM (1/4")
    Shear Typ. (kN) Tensile Typ. (kN) Grip Range (mm)
    Magna-Lok® (HRDS-0806) 11.1 8.2 2.0 – 9.5
    Hucklok® (HKLP-R8-6) 15.6 8.5 2.0 – 9.5
    Magna-Bulb® (MBDS-0806) 16.0 8.9 5.8 – 7.8
    Allok® (ARDS-08145) 13.7 7.9 5.0 – 8.5

    Can I get coloured rivets?

    Yes, painted rivets are available. They cost a little extra compared to the mill (raw) finish and are available in a wide range of colours. Refer to the Colorbond ® colour chart for your selection. 

    Why have my rivets failed?

    There are several reasons your rivets may have failed, the issue could be a dodgy rivet or an installation issue. Either way we offer a wide range of technical services, including rivet test lab services. We have teamed up with a NATA approved lab that undertakes laboratory rivet testing services. Should you have a rivet failure, let us know so we can review your application and or have your rivets sent to the NATA approved lab for laboratory rivet testing.   

    Can you assist me with rivet selection?

    Sure, the Aerobolt team can assist with the selection by either calling us on 02 9755 3747 or contact us.  

    Do you deliver rivets throughout Australia?

    Yes, we can deliver Australia wide through our network team of courier companies. In Sydney we offer our customers same day delivery if you order before 10.00am or the next day. Deliveries to regional New South Wales or major Australian cities such as Melbourne, Brisbane including regional South Eastern Australia are either next day delivery or 2 days turnaround.

    Rivet Summary.

    Rivets offer superior fastening capabilities for both heavy-duty and light fabrication applications. A rivet in one form or another has been used by people for numerous centuries and it is hard to imagine a world without rivets. They are found in the metal roofing and guttering that protect our homes, to the air conditioners that make us more comfortable to the cars we drive, the planes we fly and the ships we sail. Wherever there is a construction site or a fabrication workshop there is bound to be a rivet in use. 

    At the conclusion of this blog, it is evident that rivets are important option in numerous building and manufacturing sectors. Irrespective of the rivet type or rivet label required for your project, be assured with a bit of planning your project will end up as a successful one. Here at Aerobolt we have a comprehensive range of rivet products  and can assist in your application, simply call us on 02 9755 3747 or contact us for all your riveting requirements.

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