Roll pins are commonly used in place of bolts to connect two pieces of metal. In general, a roll pin is a solid piece of metal that fits tightly into a machined hole. These pins must occasionally be removed in order to repair machinery. Because of various circumstances, the pin may be difficult to extract.
How to Remove a Roll Pins
A Basic Drift Pin Punch
The roll pin will be exposed on both ends in the simplest extraction. A small diameter drift pin punch can be used in these situations. The diameter of the drift punch must be smaller than the diameter of the roll pin hole. Caution must be used to avoid flattening the end of the roll pins as they are extracted. Most roll pins can be pushed from their placement using a drift pin punch by using a small ball-peen hammer and striking with short strokes.
Tap and Drill
Small roll pins may be wedged tightly into place if access from the backside of the hole is not possible. In such cases, the roll pin’s center may need to be drilled out with a carbide drill bit. While drilling, use a lot of penetrating oil as a coolant. The pin’s center hole is then tapped so that a bolt can be inserted. After that, the bolt is used to extract the pin from the hole. If tapping the pin is too difficult, use a hardened, self-tapping screw. Using a screwdriver, tighten the screw. To “knock” the bolt and pin assembly out of the precision hole, a slide hammer may be required. To accommodate the size of bolt or screw threaded into the center of the roll pin, you may need to modify the end of the slide hammer. Allow some time for the oil to soak through the roll pin’s sides and into the hole. Before extracting the stuck roll pin with the slide hammer, the lubricant may help loosen it.
Some roll pins may be so tight or rusted inside the hole that the only option is to drill the pin out completely with a carbide bit. Caution is required because the drill bit may attempt to deviate from the center of the pin. This can result in an oblong or mis-centered hole. After removing the pin, the hole can be re-drilled with a slightly larger bit. Following the repairs, a larger roll pin must be inserted.