Fix and Fit

Removing Broken Screws

by Alex Yoho, ABOM

One of the most frustrating things that can happen when reconditioning eyewear is tightening a screw and having the head break off. Here are a few different ways to get those stubborn screws out.

START WITH HEAT AND OIL

Heat and oil provide a good starting point. You can heat a frame in your salt pan or hot air blower to expand the metal and somewhat loosen the screw. Adding a drop of oil when the metal is hot thins the oil and allows it to flow into the threads of the screw. You can also use a flame, but take great care not to spoil the finish. After this step, there are several ways to remove the screw.

BACK IT OUT

The ideal method to remove a broken screw is to grip it and back it out. If any part of the screw extends beyond the barrel, there is a good possibility of gripping it and backing it out. The best method is to grip the screw with a pair of sharp oblique cutters, being cautious not to cut through the screw, and back it out about a quarter turn at a time.

EMPLOY THE EASY-OUT

Some prefer to back out a screw with an easy-out, also known as a screw extractor. The device fits in your screwdriver handle and has four sharp-pointed blades that grip the end of the screw and back it out.

Although a nice idea, this method has limited success. To use this method, place the frame on a solid bench block and push hard on the end of the screw with the screw extractor. While pushing, rock the handle back and forth to slightly cut into the screw. Continue to push down, and turn the screw to back it out.

CUT A NEW SLOT

Another method is to use a screw slot file to cut a new slot into the extended screw. You can then back the screw out using a screwdriver.

This can be difficult because there is often little room to move the file back and forth. Also, it requires great skill to slot the screw exactly in the center. If there is any resistance, the new slot will often disintegrate.

DRILL IT OUT

If all else fails, you'll have to drill out the broken screw. This requires practice because it's necessary to drill exactly in the center of the screw.

Use a bit that is smaller than the diameter of the screw. After drilling through the screw, remove the remaining thin shell with a taper reamer placed in the hole until it grabs. Then, turning the reamer, unscrew the shell.

If the shell won't back out, ream the hole to size and, using a tap, create new threads for the new screw, or use a self-tapping screw. Just screw it in, and snap off the excess.

To get a clean break, bend the screw slightly in one direction, then snap it off in the opposite direction. It should break off clean at the base. EB

If you have a drill, it's often possible to spin the broken screw out rather than drill through it. Sometimes using a round, sharp dental burr works well for this. When drilling metal, always use a slow speed. This keeps your bit from burning up and allows the cutters of the burr or drill bit to grab the screw and spin it out.