"Mazak" in the UK but more widely known (at least in the US, where it was developed) and in its original form as "Zamak", this metal is notorious for disintegrating (not "exploding" as some earlier poster claimed). It is also known as "pot metal" and, unhelpfully, "white metal".
Mazak, aka pot metal, aka Zamak, is notorious for disintegrating over time. It's what can cause tab brakes on the Olympia SM7 to freeze up.
via M. Höhne at https://typewriter.boardhost.com/viewtopic.php?id=253&p=3
Olympia SM7 Typewriter - How to Remove and Repair a Stuck Tab Brake<br /> by [[The Write Typer]] YouTube<br /> accessed on 2026-03-03T23:50:21
Swelling pot metal or swollen cork can cause the tab brakes on the Olympia SM7 to seize up. One can file down the cork, or even remove one of the four brake elements and still have the system work. The brake drum is held in with an e-clip.
Addressing a COMMON FLAW in the Olympia SM7 typewriter that will ruin your day. Drawband Tab System<br /> by [[HotRodTypewriter]] on YouTube<br /> accessed on 2026-03-03T23:41:58
Remedies for frozen tab brake system on Olympia SM7 typewriters:<br /> Drill a hole and lubricate<br /> Remove all together<br /> Remove and attempt to adjust swollen cork and then attempt to reinstall (patience testing)