FASTENERS 101™
Blind (POP) Rivets 101


What Is A Blind Rivet?

Blind rivets, also commonly referred to as POP Rivets, are mainly used in applications where there is no access to the rear (blind side) of the joint. Rivets have a two-piece construction; one is called the rivet body, shell, or hat and another is called the stem or mandrel. Both the hat and mandrel are pre-assembled and ready to use. Rivets are installed by using a riveting tool to draw the mandrel which causes the body to deform and clamp down on the joint. Upon reaching the designed clamping force, the mandrel snaps and is discarded. A benefit of blind rivets are that they are not material specific meaning they can combine two different material types together the same way.

To use a blind rivet, a hole is drilled then the rivet is seated inside of the hole. Then a tool pulls the mandrel against the hat of the rivet. The back of the mandrel either has a bulge on the end or is connected to the hat in some way which makes the edges of the hat expand down towards the material. Once this expansion reaches the material and builds pressure, a designed fault in the mandrel reaches its peak force capacity and snaps. Leaving a properly installed rivet.

One of the biggest benefits if rivets is that there is no way to over or under-torque a rivet. As long as the appropriate diameter and grip range and chosen the rivet will install perfectly every time.

Pop Rivet Animation

Installing a Blind Rivet

Before rivet installation can occur several things must be taken into account.

Materials The softness/hardness of the materials may be enough to change grip range or head style during installation. Rivets come in either all one material or material/material options.
Rivet Material The rivet material must be chosen based on environmental factors, strength, corrosion resistance and installation materials.
Head Type There are several different head styles covered later in this article.
Rivet Length The length of the rivet will change the grip range.
Rivet Diameter The rivet diameter determines the size hole that needs to be drilled.
Grip Range A rivet's grip range is the range of how thick the material can be for a proper installation.

Installing a blind rivet is a simple and extremely fast process which is what gives POP rivets their excellent reputation. Installing them requires only the few simple steps listed below.

  1. Drill a hole into the materials.
  2. Choose a place the rivet into the two materials.
  3. Place the Rivet Installation Tool on the mandrel of the rivet.
  4. Activate the tool (usually by some lever or trigger mechanism) to pull the mandrel towards the surface.

When the mandrel gets tight in the material it will snap off at a predetermined point leaving the hat with a portion of the mandrel stuck inside. A properly sized and installed blind rivet will hold tightly and strong as a permanent joint in the materials. If the hole was too big the rivet will be loose and spin and if the drilled hole is too small the rivet will not install correctly leaving a bad seal.

How to Measure a Rivet

  1. Measure the diameter of the rivet itself with a dial caliper or a measuring gauge.
  2. Measure the underside of the rivet head to the end of the rivet head. *Don't Measure the mandrel. The hat length it what you are looking for.
  3. The grip range of the rivet will be 1/8" shorter than the measured length.

EXAMPLE: If the length of the hat is 1/2" the rivet has a 3/8" grip (.375), also known as a 4-6 rivet. Please refer to the diagram and charts below for grip ranges

  • Mandrel - Long end that is broken off the rivet during installation
  • Hat - Portion of the rivet that is inserted and expanded to fit a hole
Measuring Blind rivets

Understanding Rivet Grip Range


Here is an example of calculating rivet grip range using a:
6-6, 3/16" STAINLESS STEEL OPEN END DOME HEAD POP RIVET

6-6 = X-Y
Where X Represents Diameter in X/32 and Y Represents Max Grip Range in Y/16
Example:
(X=6, 6/32 = 3/16) Diameter = 3/16
(Y=6, 6/16 = 3/8) Max Grip Range: 3/8
6-6 = (3/16 x 3/8)
Grip Range .251-.375

Rivet Size Guide

Rivet Series # Nominal Size Drill Size Hole Size
Max - Min
Rivet # Grip Range
(Installed)
Body Length



3



3/32"
(0.0938)



#41



0.100 - 0.097
3-2 0.020-0.125 0.250
3-4 0.126-0.250 0.375
3-6 0.251-0.375 0.500
3-8 0.376-0.500 0.625
3-10 0.501-0.625 0.750








4








1/8"
(0.1250)








#30








0.133 - 0.129
4-1 0.020 - 0.062 0.212
4-2 0.063 - 0.125 0.275
4-3 0.126 - 0.187 0.337
4-4 0.188 - 0.250 0.400
4-5 0.251 - 0.312 0.462
4-6 0.313 - 0.375 0.525
4-8 0.376 - 0.500 0.650
4-10 0.501 - 0.625 0.775
4-12 0.626 - 0.750 0.900
4-14 0.751 - 0.875 1.025








5








5/32"
(0.1562)








#20








0.164 - 0.160
5-2 0.063 - 0.125 0.300
5-3 0.126 - 0.187 0.362
5-4 0.188 - 0.250 0.425
5-6 0.251 - 0.375 0.550
5-8 0.376 - 0.500 0.675
5-10 0.501 - 0.625 0.800
5-12 0.626 - 0.750 0.925
5-14 0.751 - 0.875 1.050
5-16 0.876 - 1.000 1.175
5-18 1.001 - 1.125 1.300










6










3/16"
(0.1875)










#11










0.196 - 0.192
6-2 0.020 - 0.187 0.325
6-3 0.126 - 0.187 0.387
6-4 0.188 - 0.250 0.450
6-6 0.251 - 0.375 0.575
6-8 0.376 - 0.500 0.700
6-10 0.501 - 0.625 0.825
6-12 0.626 - 0.750 0.950
6-14 0.751 - 0.875 1.075
6-16 0.876 - 1.000 1.200
6-18 1.001 - 1.125 1.325
6-20 1.126 - 1.250 1.450
6-22 1.251 - 1.375 1.575










8










1/4"
(0.2500)










F










0.261 - 0.257
8-2
0.020 - 0.125 0.375
8-4
0.126 - 0.250 0.500
8-6
0.251 - 0.375 0.625
8-8
0.376 - 0.500 0.750
8-10
0.501 - 0.625 0.875
8-12 0.626 - 0.750 1.000
8-14 0.751 - 0.875 1.125
8-16 0.876 - 1.000 1.250
8-18 1.001 - 1.125 1.375
8-20
1.126 - 1.250 1.500
8-22
1.251 - 1.375 1.625
8-24
1.376- 1.500
1.750

Rivet Types

Rivets come in a variety of types each of which have benefits.

Open End Open End Rivets are the most popular rivet variety available. They rely on the balled end of the mandrel going into the hat forcing it to expand.
Closed Ends Closed End Rivets are used for applications where the installed rivet will be exposed to liquids or vapors. The sealed end prevents liquids from going through the rivet into the installation or speeding up the corrosion process.
Multi-Grip Multi grip rivets have a significantly wider grip range than standard POP rivets. They are commonly used to substitute conventional rivets where the material thickness varies.
Tri-Fold (Exploding) Tri Fold or exploding rivets have a wider grip range due to the way the hat bulges. They also resist pull-though by having three folds distribute the pressure over a wider surface area.
Interlock (Structural) The mandrel locking mechanism on these rivets create a stronger assembly than other types. This type is recommended for structural applications.
Painted Head Painted rivet hats to match your applications to leave a blended less noticeable rivet in its place.

Head Styles

The head refers to the washer-like portion of the hat on a rivet. Just like with the type, each variety of head comes with its own benefits that should be considered.

Dome The dome head sits rounded and exposed when finished.
Large Flange Large Flange rivets have a wider hat to better distribute surface pressure and prevent pull-through.
Shave Head The mandrel snaps further up on these rivers requiring a cutting and filing tool to shave them down to a clean finished look. They are exceptionally popular as trailer rivet replacements.
Countersunk A Countersunk head sits almost flush with the surface when installed.
Low Profile (Flat Head) These heads are almost the same as a countersunk but sit up slightly higher.

Rivet Tools

Rivet tools (Riveters) are the special tools used to install rivets. There are several types available and options can vary depending on the size of the rivets.

Hand Riveter A very common rivet tool that is simple to use and requires only a squeeze or two to set the POP Rivets.
Lever Riveter A tool with two handles designed to drive stronger rivets such as structural. Some include a bottle to catch the snapped mandrels for ease of cleanup.
Battery Powered Riveter Like a cordless drill, a battery riveter uses a trigger and automatically pulls and spits the mandrel. Some have a catch that will draw the mandrel in for ease of cleanup.
Pneumatic Riveter An air powered rivet tool that quickly and effectively installs rivets. The only downside is needing compressed air to use.

How To Remove A Rivet

Blind Rivets are meant to be permanent joints but sometimes must be removed. To remove blind rivets, take a drill bit that is the same diameter as the hat or a size larger and drill through the rivet. Make sure the drill bit is rated for the rivet material. If before or during the rivet drilling process the rivet begins to spin, stop and cover the rivet in blue painters or duct tape. This should be enough to hold the rivet in place as the drill eats through it. Once extracted, the same hole can be used for a new rivet.

Rivet Washers

Rivet washers are useful tools to have handy. There are two main types of rivet washers. The metal ones that sit below the hat which increases the pull-through resistance and pressure distribution of a rivet and the neoprene (rubber) washer that sits below the hat to seal a hole. When using the metal washers be careful to ensure the washer's thickness is included in the thickness.

Common Blind Rivet Applications

POP Rivets can be used just about anywhere as long as they are properly installed. The majority of them are used in RVs, Trailers, Aircrafts, Machinery, Small Electronics, Structural Beams, Battleships and Submersibles.


Helpful Rivet Resource Videos:

Rivet Measuring

Rivet Types and Materials

Rivet Tools

Rivet Installation

How to Remove a Pop Rivet

How to Remove a Spinning Rivet



Shear and Tensile Strength

Nominal Rivet
Size Inch
Minimum Shear Strength (lbs)
Maximum Shear Strength (lbs)
Grade 11 Grade 19 Grade 30 Grade 51 Grade 11 Grade 19 Grade 30 Grade 51
3/32"
(0.0938)
70 90 130 230 80 120 170 280
1/8"
(0.1250)
120 170 260 420 150 220 310 530
5/32"
(0.1562)
190 260 370 650 230 350 470 820
3/16"
(0.1875)
260 380 540 950 320 500 680 1200
1/4"
(0.2500)
460 700 1000 1700 560 920 1240 2100

The grade of material will directly affect the materials strength.


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