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Exposed Rivet Construction
Exposed rivet construction refers to applications where the head of the rivet is visible on the finished product. Exposed rivet construction is much simpler than concealed rivet construction, and will be discussed first.

In loose leaf binders, rings or any other hardware is typically installed using rivets. Rivet configurations fall into two main categories: semi-tubular rivets and plain (also known as cold or solid) rivets. Semi-tubular rivets are rolled or curled during fastening, while plain rivets are swedged, or smashed. See the diagrams below.

Semi-tubular Rivet

Plain Rivet

The semi-tubular rivet on the left has a recess in the end of the barrel. Generally, semi-tubular rivets will have a less crowned head than plain rivets. The plain rivet on the right tends to have a "button" shaped head and does not have a recess in the barrel.

To fasten a semi-tubular rivet, the tubular barrel end of the rivet is turned or curled. This creates the familiar doughnut that is seen on the inside of a loose leaf binder on the ring chassis cover. See the diagram below.

Rivet with turned barrel

The plain rivet is fastened by simply flattening the barrel end with a hammer. Plain rivets are most commonly used in metal work, but are occasionally used in loose leaf applications as well. The head of both plain and semi-tubular rivets has a flat underside, reducing the chance of the rivet head pulling through most types of board.

The length of a rivet is measured from under the head of the rivet to the end of the barrel. For most loose leaf and luggage hardware work, the barrel diameter is 9/64" and the length will range from 3/16" to 5/8". Rivets with a 1/8" barrel diameter are commonly used for luggage hardware rivets for hinges and latches. The required length of the rivet is determined with the following formula:

Combined height of hardware + thickness of substrate + 1/16" (for turning).

Concealed Rivet Construction
There is much more to be considered when the rivet installation is of the concealed type. While some concealed rivet construction is done with the semi-tubular or plain rivets discussed above, most concealed rivet applications using aluminum rivets. The softer aluminum allows the rivet to be "set" or turned without damaging fabrics or vinyls that cover the head of the rivet.

Two types of aluminum rivets are typically used in concealed rivet applications: semi-tubular flathead rivets and staking rivets. Both types have recess in the end of the barrel for turning or curling, as discussed above.

Semi-tubular, flathead rivet

Staking rivet

There are several important differences between these two types of rivets. Most notable is the angle on the underside of the rivet head, which has a great effect on how easily the rivet can be pulled out. The semi-tubular flathead rivet has a larger angle, meaning that in can easily pulled through the board that it is riveted to. If the board is soft, or a low density board, there is less resistance to the rivet coming through. Certain ring installations, such as back cover mounting, put additional strain on the rivet, increasing the possibility of "pull through". A standard spine installation is not as fragile.

Staking rivets (sometimes referred to incorrectly as "shoulder rivets") have a ledge on the barrel. This type of rivet is set in a two-part operation. First, special riveting equipment sets the rivet in the substrate by turning the ledge. Then, the barrel of the rivet is turned as usual. The angle under the head of a staking rivet is shallow, and therefore less likely to break through the board. However, the width of the ledge area means that the angled area is smaller, which is a trade off.

The purpose of the angled head on the semi-tubular flathead and staking aluminum rivets is to allow the head of the rivet to be flush with the surface of the substrate that it is installed in. As the rivet barrel is turned, the rivet head is drawn into the substrate; the angled head facilitates this "sinking" effect. Both types of rivets are often referred to as either flat head style or countersunk style. They are measured in length from the top of the head to the end of the barrel. Typically, they are the same barrel diameter as the standard semi-tubular rivets (9/64").

It is important to note that any of the rivet styles mentioned above will work in most types of ring and hardware installations. However, it is extremely uncommon that the concealed rivets will be used with a large capacity ring mechanism (2 1/2" or larger). There is simply too great of a chance that the rivet will pull through the board. Likewise, handle hardware on a sample case is usually done with steel rivets for the same reason; they are less likely to pull through when installed correctly.

Rivet Installation
Semi-tubular, exposed rivets are typically made of steel. Rivets sold specifically for loose leaf are usually made of "malleable" steel (somewhat soft, formable steel). They are installed and turned in one operation on riveting machinery.

Aluminum rivets are installed in one operation and then set later. The setting operation can be done by hand or with a hammer and setting tool, an air powered impact tool or on a riveting machine designed to turn the rivet barrel only.

Staking rivets are installed first on a piece of equipment specifically designed to spread the "ledge" of the rivet without disturbing the barrel. Later they are set in the same fashion as the other types of aluminum rivets.

The "plain barrel" aluminum rivets are often installed by hand after the substrate had been drilled, punched or die cut to create a rivet hole. Occasionally, they are installed by using a riveter that has been modified to put these rivets through a spine or panel without drilling and without turning the end of the barrel. A thin pieces of chipboard, used as "support" is frequently used over this type of rivet to prevent marking of the material when the barrel is hammered, turned, curled or in some way set.

Rivet Installation Options
The following diagrams illustrate aluminum rivet installation options.

Note that no supporting material is required when using a staking rivet. The ledge of the staking rivet has been turned down over the edge of the board, locking the rivet into place. Later, the end of the barrel will be turned over.

One away to avoid the "pull through" problem is to use a rivet with a large head. However, it is difficult to conceal such a rivet without creating an unsightly bulge on the finished cover.

Alternatives to Traditional Rivets
For many years, picture frame hardware and some jewelry box hardware has been installed using a "losat" or "lozat". A losat is a set of teeth, usually punches out of the body of the hardware. When the hardware is installed with pressure, the teeth enter the substrate and spread, securing the part to the board or whatever other substrate is being used.

Recently, loose leaf metals with this type of toothed appliance became available. These rings are installed by pressure without rivets. Many types of riveters and be easily modified to install "rivetless" or "prong bushing" metals. Since the metal is installed from the inside, this type of meta is essentially considered concealed rivet construction.

The best feature of these metals is that they eliminate much of the concern about mounting in low density board. There are still potential problems when installing large metals in the back cover, so we do not recommend this type of installation with ring capacities 2 1/2" or greater. However, these rivetless rings in capacities of 2" and less will install very solidly in low density board, and are actually a far better means of achieving concealed rivet construction in low density board.