Pop rivets are tubular in shape with mandrels through the center. The rivet itself is inserted into a previously drilled hole, through the metals you're joining, and then locked into place by means of a rivet gun.
The mandrel is drawn until it snaps off, leaving behind a hollow rivet that fastens two pieces of metal securely. Although pop rivets are commonly used, the process of removing them can be difficult due to an absence of threads or head that can be used to pull it out.
The normal practice is to do the removal with the same drill that was used in drilling the hole for the rivet, but this also usually enlarges the existing hole, necessitating the use of a bigger rivet size for re-riveting.
There are also instances where a blind rivet needs to be removed but an electric drill cannot be found. In such situations, you will have to make do with a different removal method.
Step 1 - Assessing the Materials
The first thing you should do is assess the materials that have been fastened by a blind rivet. The thickness will determine which method might be better to use and the amount of force that you can use to remove rivets without drilling.
Flimsy materials such as thin metal sheets may crumple or even be torn off with too much force, leaving the whole point of removing the pop rivets useless.
Step 2 - Removing the Pop Rivet Head
A blind rivet is removed with a power drill by drilling on the hollow part of the rivet head until it comes off the shank. The same can be done by using a flat head screwdriver or chisel and a hammer. Place the tip of the tool between the material and the rivet head and tap it with a hammer until the head breaks off.
Be careful with the amount of force you use, as it can still destroy thicker material even though sturdy metal can take a good whacking. Thin sheets may require you to do gentle but repetitive taps.
Step 3 - Pushing Out the Pop Rivet Shank
Once you have cut the blind rivet head, use a thin screwdriver or a small rod to push the rivet shank out of the hole. It may come out with a single tap if the material is thin, or you may have to use the hammer with more force and repetition for thicker materials.
Step 4 - Using a Dremel
Alternatively, you can use a Dremel rotary tool. A small, circular cutter comes as one of the Dremel's attachments and this can be used to cut off the head of the blind rivet. However, make sure that you can use the power tool with enough dexterity to avoid cutting the material as well.
A circular cutter has a wider contact with the surface you are working on, no matter how small, compared to a power drill. Hence, the chances of damaging the surrounding areas are also higher. Once you have successfully removed the head of the pop rivet, push the rivet shank out as indicated in the previous step.