BEFORE TABS
The church key
Drinkers used a can piercer to punch two triangular holes in the top, one for drinking and one to let air in.
Compare the openersEVERYDAY DESIGN, EXPLAINED
The opener
that stayed on.
A small lever with a long, messy history.
PSSHHT one rivet, one lever
1959 Year of the picnic that started it
- A rivet holds the tab
- The tab is a lever
- Nothing comes off
- Small fix, billions of cans
Before tabs, a can of beer needed a tool and two holes. The ring pull of the 1960s made cans self-opening but left sharp rings everywhere. The stay-on tab patented in 1976 fixed that by keeping the lever, and the flap, attached to the can.
THE SHORT ANSWER
Church key, ring pull,
stay-on tab.
First a tool, then a tab that came off,
then a tab that stays on.
THE RING PULL
Self-opening, but loose
From the early 1960s a riveted tab turned into a lever that tore out a pre-scored strip. It came right off, and was often dropped.
See the numbers
THE STAY-ON TAB
Push in, fold back
The 1976 design pushes a scored panel into the can, where it stays attached at a hinge, and the tab stays on too.
How it worksCOMPARE THE OPENERS
Which opener
caused the most trouble?
Pick an opener to see how it worked. The bar shows how much trouble it caused, from litter to cut fingers, according to the sources.
Based on Smithsonian Magazine and the Wikipedia history of the beverage can.
INSIDE THE TOP OF A CAN
How a stay-on tab
opens a can.
The modern can end is a small piece of engineering. These are the parts the patents and histories describe.
The rivet
A small metal pin fixes the tab to the lid, so it can pivot but not come off.
The score line
A pre-scored curve outlines the panel that will open.
The lever
Lifting the back of the tab presses its front down on the panel, which snaps open.
The hinge
Part of the score is left uncut, so the panel bends into the can and stays attached.
TWO NUMBERS WORTH KNOWING
From picnic to patent:
1959 to 1976.
When the idea came,
and how long the fix took.
1959
Year of the picnic that started it
Dayton toolmaker Ermal Fraze forgot his church key and had to open a can on his car. He set out to build an opener into the can itself.
THE SPARK · SMITHSONIAN
1976
Year the stay-on tab patent was granted
Engineer Daniel F. Cudzik's easy-open wall was granted on 6 July 1976. Wikipedia notes the stay-tab has been characteristic of most drinking cans since the mid-1980s.
THE FIX · US PATENT 3,967,752
Fraze himself told an interviewer in 1963 that he had not invented the easy-open can end, which people had worked on since 1800; what he developed was a way of attaching a tab to the can top.
WHY THE RING PULL HAD TO GO
Litter, cuts
and swallowed rings.
Smithsonian Magazine reports that through the 1960s and 70s detached tabs littered streets, pavements and beaches. Some bartenders disliked the sharp edge so much that they opened cans from the bottom instead.
Worse, people often dropped the ring into the can before drinking, as some environmentalists had advised to cut litter, and swallowed tabs became a medical problem. Wikipedia notes that a 1976 medical journal reported children swallowing tabs that had broken off.
Questions
Questions people ask
What is a church key?
A small double-ended tool: one end is triangular for piercing cans, the other rounded for opening bottles. In the 1950s drinkers used it to punch two holes in a can.
Who invented the ring pull?
Smithsonian Magazine credits Ermal Fraze of Dayton, Ohio, who after a 1959 picnic developed a riveted tab that worked as a lever. Ring pull is the British English name for the pull-tab.
Who invented the stay-on tab?
Engineer Daniel F. Cudzik. His patents for an easy-open wall, US 3,967,752 and 3,967,753, were granted on 6 July 1976.
Why does the tab stay on now?
Because it is riveted to the lid and only pushes the scored panel inwards. The panel stays attached at an unscored hinge, so nothing comes away.
Are full pull-off lids still used?
Yes. Wikipedia notes full-top pull tabs are still used on some soup, pet food, tennis ball and nut cans.
How were cans opened before the church key?
Smithsonian Magazine says the first tin-coated iron cans, patented by Peter Durand in 1810, were opened with a chisel and hammer. Ezra J. Warner patented the first can opener in 1858, a blade that sawed round the rim, and Charles A. Bunker patented the modern can opener in 1926. Both removed the whole lid, which suits beans but not a drink.
Did Ermal Fraze design a stay-on tab too?
Yes. Smithsonian Magazine reports that Fraze patented his own version, the Easy-Open Ecology End, in 1977, the year after Daniel F. Cudzik of Reynolds Metal Co. patented the Stay-On-Tab. A patent battle followed and was ultimately decided in Cudzik's favour.
Why did aluminium help the ring pull take off?
Smithsonian Magazine quotes Peter Liebhold, curator emeritus at the National Museum of American History: cans had historically been made of steel, aluminium was taking over the can industry, and it is easier to make a pop-top from aluminium than from steel. Fraze sold his first design to Alcoa, which put it on Iron City Beer cans.
Where the facts come from
Updated