Thursday, 24 October 2013

Slightly less weird stoppers

By the 1880's two camps had emerged in the search for the perfect stopper. On the one side were the adherents of internal devices like the Codd stopper. On the other, those who favoured an external "over the top" stopper like the various forms of flip top. Neither was perfect.

"The "over the top" supporters held their type of closure to be superior from the point of view that the pouring lip of the botde was protected from dirt and that the removal action could be more gradual, allowing top pressure to escape slowly and so eliminate the excessive fobbing. The bottle could be filled in its natural position and satisfactorily cleaned inside. These were undoubtedly favourable points, but it remained an unfortunate fact that up to then they had been unable to produce a successful pressure-holding closure without the aid of wire bails or like appendages.

The problem of the "interior" sealers was to make a closure that could be applied from the outside and be removed outwardly leaving an unobstructed interior. That of the "exterior" sealers was to find a cap that was sufficiently strong to hold high pressures. This then was the situation at the time that William Painter entered the field."
"Background to the Crown" by Cecil J. Parker.

I'd never considered just how difficult it is to design an exterior stopper capable of resisting the pressure inside a beer bottle. A crown cork seems such a simple and obvious solution. Why did it take so long to be invented?

Well, we're getting closer to that invention. Because now the key figure appears on the scene: William Painter. The man who finally came up with the crown cork. But not quite yet. Because he started out in the internal stopper camp.

"William Painter, of English descent, lived at Baltimore in Maryland. By trade he was a Mechanical Engineer and by nature a genius in things mechanical. During his working career he took out over eighty patents covering many widely divergent subjects. Possessed of an extremely active brain and an "up and doing" temperament he was for ever thinking out something new and then making it.

We cannot know for certain how he became interested in the bottle closure problem, but as so many others were at that time, it is more than likely that his position as foreman in an engineenng shop brought him into contact with an inventor who was having working models made of some form of stopper. We do know, however, that in September of 1885 William Painter's name appears in the English Patent Office records as co-inventor with another of an "interior" seal stopper. See Plate 7.

It was a very simple invention, as will be seen from the drawings which show A, the earliest form ; B, later form with stud ; and C alternate form with wire loop. These were to facilitate opening! The scaling disc was made from some flexible material such as rubber. It was of greater diameter than the neck of the bottle and was pushed into the latter in such manner that a convex surface was presented to the interior, the principle being that pressure from within the bottle would tend to flatten the disc and so tighten it against the inside of the neck."
"Background to the Crown" by Cecil J. Parker.

Simple, yes. Effective? I doubt it. Looks very flimsy to me, even the later versions. How exactly did you get the stopper out? Or did you just push it in?

"It is fairly obvious that at this time William Painter did not have a very extensive knowledge of the practical side of bottle sealing. In the earliest form it will be seen that while there was an inner shoulder to the bottle neck to prevent the sealing disc from sliding out under internal pressure, no means were provided to ensure that it did not penetrate too far when inserted. This was rectified in the later forms by change of the neck finish. Another curious point concerning the earliest specification is that alternative to india-rubber, the disc, it was said, might be made of linoleum.

For some years Painter worked hard to make a go of this closure. A certain degree of success was undoubtedly achieved, for 1890 found him taking out patents for a combined filling and stoppering machine, tongs for forming the bottle necks and another machine for fixing wire lifting loops to the sealing discs. It is significant, however, that at the same time he was patenting a spring bail for holding the stopper in place during pasteurization. From this it would appear that its pressure holding capacity was not all that could be wished for and this probably altered the trend of his thoughts from inner to outer sealing."
"Background to the Crown" by Cecil J. Parker.

It's that change of heart that lay behind the invetion of the crown cork. About which we'll hear next time.


Shawn said...

I can't help thinking that these diagrams look like scientific drawings of reproductive parts. I have the mind of a child.

Ron Pattinson said...


no, you have the mind of a pervert.

Personally, I found the last det more evocative in that way.