Glossary of Terms

This is an alphabetical listing of technical lingo or specialised words that are found on the Huck Aerobolt website.   

Adhesive:  A high strength glue for the purpose of joining of two materials. 

Adjustable Feet: An essential item because most floors are not truly level. They work by simply being a threaded shaft (stud) with a perpendicular base that acts like a foot, the stud bolts into a threaded tube insert  and can be lengthened or shortened independently of each other until the item they are attached to is level. 

Anvil: An alternate name for a nutsert tool nose piece.

Blind: Refers to a one-side installation where access to the rear (blind side) is not required

Bulb: The body of the rivet or rivet nut after installation, located on the blind side of the material.  

Bulge: This relates to the body of the rivet or rivet nut. Upon installation the body of these fasteners reduce in length but radially expand to create a bulge.  

Closed End: The term used to describe a nutsert or rivet that is fully enclosed on one side. 

Countersinking:  A drilling process that creates a conical cavity for the head of a countersunk fastener to sit within and be flush with the surrounding material.

Countersunk Head: Head style that allows for a flush finish with the surrounding material.

Curing: Letting it dry, commonly mentioned with adhesives, sealant and silicones.  

Dome head: A round curved formation that sits on top of the material.  

Flat Head: An alternative name for a countersunk head

Full Hex: Hex shape nutserts where the shank is predominately a hex shape with a lead-in chamfer to facilitate hole insertion. The hex shank is designed to be installed in a hex hole and offers improved spin-out resistance compared to semi-hex shape and round shape nutserts. 

Green strength: This is when an adhesives provide an initial bond before curing. Good green strength can reduce the need for clamps and other holding or supporting devices, this in turn can lower production costs. 

Grip range: The actual depth of the material, or material thickness, or material gauge which a fastener will hold. Described within a range of minimum and maximum properties, it is important to note that the maximum grip range is not the length of the rivet or the shank of the bolt.

Half Hex: A Hex shape nutsert where the shank is half hex and half circular in shape. The hex shank is designed to be installed in a hex hole and offers improved spin-out resistance compared to round body nutserts. 

Head: The top part of a fastener that either engages with the tool, like a screw and or assists in locking the material into place, like a Huck bolt or nutsert. Heads styles include dome, truss, countersunk, and so much more.

High tack: This is the ability of adhesives to instantaneously form a bond to a substrate. An adhesive that possess high green strength tends to be very sticky,  giving them the ability to quickly start forming an adhesion.   

Huck®: This is the registered trademark of Huck International, now part of Howmet Aerospace. The Huck bolt was developed to solve the problem associated with loosening fasteners in continuous vibration application. This was cleverly resolved in 1944, when Louis C. Huck sketched the first vibration-resistant lock bolt, which went on to become the famous Huck bolt.

Huck bolts: This consist of two pieces: a threaded pin and a collar. Huck bolts work differently to a threaded bolt and nut, as they are installed via an industrial tool that swages the collar onto the grooves of the pin, making them as one, this is ideal when seeking a vibration resistant solution. They are also known as Lock Bolts.

Imperial: A term applied to a standard of measurement that is rarely used in Australia. The system is based on feet, inches, pounds, gallons etc. On this website you will see it with a double prime “or the letters ‘in’. 

Joint Sealant: A low strength product that is perfect for filling and sealing the gaps between different materials. 

Knurled: A line pattern that can be horizontal, vertical, diagonal or criss-cross embedded onto a surface. The knurled or splined pattern assists to bite into the parent material upon installation, allowing for improved torque resistance compared to standard smooth bodied nutserts.

Lab: Place used for experiments and research. 

Laboratory: Place used for experiments and research. 

Leveling Feet. An essential item because most floors are not truly level. They work by simply being a threaded shaft (stud) with a perpendicular base that acts like a foot, the stud bolts into a threaded tube insert  and can be lengthened or shortened independently of each other until the item they are attached to is level. 

Metric: Term applied to standard of measurement. The metric system is based on millimetres, centimetres, meters, litres, kilograms, etc. as the unit of measurement. The is represented by a capital “M” for the word metric or “mm” for millimetres. 

Mandrel: A gently tapered pin which material can be forged on. A mandrel can be a threaded nose piece of the nutsert tool that engages the thread of the nutsert or the pin component of the rivet that engages with rivet tool.  

Maumac®: This is the registered trademark of Aerobolt Australia Pty Ltd. Originally from the business name Maumac Distributors.

Max. Grip: Maximum depth of material into which fastener can be installed.  If the material is thicker than this value, the fastener will not be able to form correctly and fail to hold material adequately.

Min. Grip: Minimum depth of material into which fastener can be installed.  If the material is thinner than this value, the fastener will not be able to form correctly and fail to hold material adequately.

Nose assembly: A critical component of a Huck gun for the installation of a pin & collar Huck bolt or a structural rivet. The two fastener types can be installed with the same tool via an interchangeable and different nose assembly.

Nosepiece: The component of a nutsert tool that guides the mandrel.

Nutsert: Knurled body tube with an internal thread that attaches onto a surface for bolting purposes.

Open end: The term used to describe a nutsert or rivet that is hollow.   

Orlock® Rivet: Orlock® rivet secures the material on both sides of the application with better strength than some multi-grip structural rivets but with a limited material grip range. Orlock® rivet is popular due to its compact blind-side bulb that avoids pull-through, also known as Ornit® or Orlock® rivets. Check the structural rivet blog. 

Pop®: The registered trademark of the original rivet company. Sometimes people refer to rivets as pop rivets.

Pre-bulbed:The practice of starting the bulb during the manufacture of the Plus Nut Threaded Inserts.  This is done to reduce the installation load required.  The major disadvantage of this practice is that it requires a larger mounting hole to clear the bulb. 

Pull-Out: The force required to upset the nutsert when a fastener axial load is applied in a pulling direction from the head side. 

Push-Out: The force required to upset the nutsert when an axial load is applied in a pushing direction from the head side.

Ribbed / Splined: A line pattern that can be horizontal or vertical embedded onto a material. 

Rivets: A one-piece 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.

Rivnut: A tube with an internal thread that attaches onto a surface for bolting purposes, where a hole opening is not possible. Also the registered trademark of Rivnut Fastening Systems Pty Ltd. 

Rivtec®: This is the registered trademark of Rivtec Limited.

Sealant: A low strength product that is perfect for filling and sealing the gaps between different materials. 

Shank: The portion of the fastener under the head.

Shear: Shear strength is the maximum amount of sliding stress a material or component can take before yielding or tearing.  Shear pressure is applied 90 degrees to the axis of the fastener.  

Silicone: Silicone is predominantly a low strength joint sealant and is a popular category description when referring to sealants.Ideal in numerous construction application. This product is not paintable. 

Slotted Shank: The generic term for the body part of the Plus Nut or Jack Nut threaded insert. Slotting the shank allows a larger grip range and produces a cross shape bulb.  The slotted shank Plus Nut has thick walls and therefore high upset loads.  They are sometimes pre-bulbed to reduce the upset load.

Spinning out: This is when a fastener does not install or tighten up correctly. The fastener is loose and is not engaging the material.  

Spin-Pull: A type of nutsert tool that applies the upset load by first turning a mandrel into the threads of the nutsert with a low torque and then apply a pulling force to the mandrel.  After the part has been upset by the pulling action, the mandrel is turned in the opposite direction to remove it.  For this reason, a more proper term for this type of tool that is sometimes used is spin-pull-spin.  Compared to spin-spin tools, these tools are more complex, heavier, more expensive, and more difficult to setup. 

Spin-Spin: A type of nutsert tool that applies the upset load by turning a threaded mandrel into the threads of the nutsert.  The mandrel is driven by an air motor through reduction gearing.  A thrust bearing is used to reduce frictional torque resulting from the applied load.  Spin-spin tools are light weight and inexpensive and come with varying amounts of gearing.  As thread size increases additional gearing is used to increase torque output at the expense of speed. The stall torque is adjusted by air pressure.  Operation is simple, spin in to stall and then reverse the trigger and spin out.  Hence the spin-spin terminology. To prevent the insert from rotating, a serrated nosepiece must be used and therefore significant marring of the insert head occurs.

Stroke: Stroke is the length the gun’s piston retracts whilst installing a fastener.

Structural rivets: Structural rivets work differently to standard rivets, as there is an internal mechanism that locks a portion of the pin (mandrel) inside the rivet's body. This creates an additional layer of material that assists in increasing the rivets strength. 

Swage: This is a process that forces a non-threaded collar into the annular grooves of a pin. Commonly associated with Huck bolts and many other lock bolts.

Tack: This is the ability of adhesives to instantaneously form a bond to a substrate. An adhesive that posses high green strength tend to have good tack which gives them the ability to form a permanent bond between two components.  

Tensile: Tensile strength is the maximum amount of stress that a material can withstand whilst being stretched or pulled. 

Torque: Refers to the twisting force that tends to cause rotation

Truss head: A round wide shallow head compared to dome head.

Tube Threaded Insert. The female component of a levelling foot that can be found in many appliances, machinery and furniture that need to be level. This makes the threaded tube insert and the adjustable levelling foot a two-piece combo. The tube threaded insert provides the permanent internal thread that allows the adjustable foot to screw into place, whilst still having the ability to be lengthened or shortened.

Upset: The term used as a verb to describe the act of forming a bulb or bulge when installing a rivet or nutsert.

Xtralok®: The registered trademark of Aerobolt Australia Pty Ltd. This trade mark is synonymous with quality fastener products.