Published Dec 15, 2011

Use a tap & die set as thread cleaners

An inexpensive set can be a life-saver

Amazon has a large selection of inexpensive tap & die sets

When restoring or repairing stuff, I often find that threads can be gunked up with old grease, dirt, rust, making it unnecessarily hard to turn. The easiest way to clean these threads out is a tap & die set.

Normally, you'd use a tap/die to actually cut threads, but here you just want to clean them out. Although, if the threads are damaged, a tap/die is an easy way to get things straightened out. In any case, we don't need to do any precision work and you'll be running these through dirt and who-knows-what else, so a cheap set will do.

The first step will be to identify the threads you're trying to clean. Unless you're good enough to do it by eye (my dad was) invest in some Thread Detectives. Once you know what you're dealing with, just pick the matching tap or die and spin it onto the threads.

If you're using a die (the one with the cutters on the inside) note that there's a front and back. The front cutters are smaller, since they would be doing the initial cutting on the shaft. Start with that side first, so they get the upper layers of gunk off. In the photo, I'm showing the die only, normally you'd use a die handle or other wrench. I left that off so you can see the die clearly.

A tap would be used to clean out nuts or threaded holes. Again, I've left out the tap handle for clarity.

In either case, every turn or two, back off a quarter-turn to clear the buildup on the cutters. It goes a lot smoother that way.