Drafting Pencil Lead Sleeve Repair

A drafting pencil is a mechanical pencil with a long (~4mm), thin tip called a “lead sleeve” that makes it great for scribing along the edges of rulers, also making it easy to see what you’re writing. Unfortunately, the thin lead sleeve gets damaged very easily when the pencil is dropped, breaking the brittle graphite inside as it’s forced through. Although it’s usually possible to un-bend a bent sleeve by pushing it on the edge of a table, a particularly violent impact can cause an unfixable dent. (Based on my experience, drafting pencils are a poor choice for emotionally volatile people.) I initially tried using pliers to shape the lead sleeve back into shape, but at the precision of a lead sleeve, it doesn’t work. A thin dissection pin, ideal for unclogging 3D printer nozzles, was just the right diameter to potentially push the dent back out, but it couldn’t be simply forced into the dent without bending the needle.

By unscrewing the tip from the rest of the pencil and holding it in a drill press (a hand drill might also work if you can hold it still) and spinning it, the pin could be inserted with the help of pliers, successfully removing the dent. It’s a good idea to buy multiple sizes of pins to figure out the exact size needed, also, you might want to push the dent out by increasing the pin size little by little.