Auto Body Shop Equipment Distribution
Copyright: Pro Line Systems International Inc. 2002
Making Expensive Equipment Affordable "Since 2002"
GYS Welder in operation by technician
American Freedom Frame Machine
Go to content

Rivet Bonding Techniques That Enhance Heavy-Duty Truck Repairs

Pro Line Systems International-Auto Body Shop Equipment
Published by Pro Line Systems in Body Shop Equipment · 17 August 2022
Tags: SelfPiercingRivetBondingOnCars&HeavyDutyTrucks

Rivet Bonding Techniques That Can Enhance Heavy-duty Truck Repairs

  
Heavy-duty truck OEMs commonly use rivet bonding, a technique that combines rivets and adhesives to bond panels together. Rivet bonding is used to join side and back panels, front hood closures, headliners, and many inter-structural reinforcements of cab designs. Despite this, collision repair professionals unfamiliar with rivet bonding may be unable to perform quality repairs.

All About Rivet Repairs

When it comes to rivets, there are several things to think about. Rivets are lovely for creating a bond between panels in the factory, but with the vibration and movement, fatigue, and corrosion that takes place, bond failures can occur. When dealing with dissimilar substrates, we encounter a significant issue: physics.

For example, galvanic corrosion is common when an aluminous panel comes into contact with a steel rivet. When an electrolyte such as an acid, moisture, or road salt is present, corrosion can start quickly. If the joint is not sealed correctly, corrosion can occur.
  
Heavy-duty truck OEMs may apply corrosion-resistant coatings to aluminum and other metal panel rivets. However, the technician may disassemble these panels, exposing the bare metal. Sometimes, these panels will be fastened together without corrosion protection again. This may compromise the repair and tarnish the repair facility's reputation.

Exceptional safety and substrate preparation precautions are required to work with aluminum, as well as proper process mapping and workplace hygiene. Follow these guidelines when repairing aluminum and mixed metal materials. A repair failure may occur if an error is made or a step is skipped in the procedure. Educate yourself about the proper practice for working with aluminum and mixed metal materials.
 

An overview of rivet bonding with adhesives.

 
 The adhesive is used as a bonder and an isolator in this process.
 
  1. Make sure the service part fits appropriately on the host panel mating flange by straightening it.
  2.  
  3. Rivets that require drilling should be drilled and deburred if clamped and drilled holes are desired.
  4.  
  5. Clean with an approved low-VOC-compliant surface cleaner on the truck body and the service part.
  6.  
  7. Using an 80-grit dual-action sander, sand the mating flanges on the truck and the service part. (Remember: On aluminum, the surface must be coated within one hour to avoid surface oxidation.
  8.  
  9. Clean both surfaces with a low-VOC wax and grease-removing substance.
  10.  
  11. After coating the mating flange with a thin adhesive layer, apply a filler or acid brush to cover any bare metal.
  12.  
  13. Before inserting rivets, apply a thin coat of adhesive on the edges of the drilled holes to cover the exposed metal. You can achieve a sufficient bond-line thickness by applying a second bead of adhesive.
  14.  
  15. Make sure to apply enough bond line thickness by using a second bead of adhesive and clamping the part in place.
  16.  
  17. Use the correct rivet specified by the manufacturer.
  18.  
  19. Before the adhesive curing, remove the clamps and any excess squeeze-out. Grinding cured adhesive can create corrosion hot spots and collateral damage.

 

Rivet Bonding using an adhesive only as an isolator.


This procedure uses an adhesive bond as an isolator between dissimilar metal panels. Is this desirable? When bonding large panels with rivets or fasteners and when an adhesive bond is not needed, but the need to isolate dissimilar metal panels is necessary, an isolator may be used to connect the metals. When wet adhesives or sealers are used to handle large panels, the handling can become difficult.
 
  1. Make sure the service part fits appropriately on the host panel mating flange by straightening it.
  2.  
  3. Use a low-VOC-compliant surface cleaner to clean the service part and the truck body.
  4.  
  5. Sand the truck's and service parts' mating flanges using a 3M 80-grit dual-action sander. Remember, on aluminum. The surface must be coated within one hour to prevent surface oxidation.
  6.  
  7. Clean both surfaces with a low-VOC wax and grease remover that is approved.
  8.  
  9. Use a filler spreader or acid brush to cover the bare metal areas of the mating flanges with adhesive. Apply a thin, even layer of adhesive using a filler spreader or acid brush. Do not apply any additional adhesive.
  10.  
  11. Allow the adhesive to cure according to the manufacturer's instructions.
  12.  
  13. Rivets that require drilling may be installed on the panels if clamped, drilled, and deburred as necessary. Cover any exposed metal with a thin layer of the adhesive before inserting the rivet by covering the holes' edges with adhesive.
  14.  
  15. Use the correct rivet specified by the manufacturer.
  16.  
  17. Remove any excess adhesive before it cures to prevent corrosion and collateral damage.
 
 

Selecting the correct rivet


Choosing the appropriate type of rivet for a particular repair can be confusing. Heavy-duty truck OEMs use a variety of rivets such as self-piercing rivets, blind rivets, countersink rivets, solid rivets, Magna Bulbs®, and Monobolts®, among others. Rivets come in various metals, including aluminum, stainless steel, and high-strength steel. Each rivet type has a specific shear strength, tensile strength, grip range, clamping force, application technique, and tool requirement.

The size, shape, and length of the rivet and its location and accessibility to the repair area may significantly impact which rivet is proper. OEM specifications, technical bulletins, and repair recommendations are just some resources available.
  

Rivet Installation
  
Self-piercing rivets (SPRs) are produced from specially coated high-strength steel. Rivet installation methods can vary from one type to the next. For example, both panels require drilling holes for solid and blind rivets. An improperly fitted panel can result if burrs are not removed after drilling. Countersink rivets are also used in solid and blind rivets. Because the head angle of a countersunk rivet is typically 90 degrees, thinning of the aluminum is prevented by using the correct countersink bit when setting the rivet.
 
 
Since SPRs are designed to pierce the sheeting and expand outward, they don't necessitate pre-drilled holes or deburring. For example, rivets that are compressed at a certain speed with a specific tool may also be compressed. The rivet body material flows out and fills the intended space when the rivet is compressed with the correct tool. If compressed too rapidly, it may create voids, or the metal may harden and cause the rivet to break down over time. Using manual tools and making multiple compressions can cause the rivet or fastener to harden, fatigue, crack, or compress unevenly, resulting in failure.
 
Example Of A Very Popular SPR & Flow Form Riveter - GYSPRESS 10T
Click Photo To Learn More

Rivet Removal Options
  
There are various ways to remove rivets, depending on the type. For example, a bucking bar and an air hammer are used to install solid rivets. The bucktail is created by flaring the backside of the rivet.
 
In most situations, a 2" or 3" 3M™ Roloc™ abrasive disc is used to grind off rivet bucktails. However, this can also significantly damage the host panel if the material surrounding the rivet is also scraped away. A technician may avoid this by using a 3M File Belt Tool with a 60-grit belt to grind down the bucktail with minimal damage to the surrounding metal.
 
 Drill a pilot hole from the back of the rivet head to stick a drill bit into place if you wish to remove an SPR. An SPR can be removed by drilling out the rivet with a unique removal tool, but this may be difficult as SPRs are made from high-strength steel. It may not be easy to drill out SPRs because they are high-strength steel.

A belt sander may also be used to grind off SPRs from the back, but be sure to reduce the speed of the electric drill to prevent rapid dulling. To grind off the SPR, the 3M Roloc™ File Belt Tool equipped with a 60-grit belt is an excellent choice. It is possible to grind the SPR off on the front or back with very little damage to the host panel.
  
Rivet or fastener type, tool availability, panel access, and technician safety are all things to consider when selecting a self-piercing rivet removal method.
  
Rivet bonding is an efficient and quick method of joining panels in truck repair facilities. Although this practice is relatively new in some repair facilities, it has been widely used in the automotive sector. When repairing heavy-duty trucks, the procedure is the same as for other vehicles, except for the size.

The OEM design of a heavy-duty truck must be thoroughly understood, and then the required and suggested repairs must be determined. Since numerous variables affect a single repair, the technician and repair facility must evaluate each situation and choose a suitable method.
  
Are you looking for an Auto Body Repair Equipment Supplier that provides best-in-class auto body repair equipment and great support? Click here to learn more about Pro Line Systems International Inc. and get a quote.

FYI: Hey, Curious about Giulio Valle, the Authoritative Author, and creator of this Blog and the
5 star rating

Call us for free consultation:
pro line systems contact form
 


comments powered by Disqus
Back to content