When were sliding HexagON taps introduced?

[cardan]

I've been sorting out my petrol taps. Most of my old bikes use lever taps, so I don't know much about the sliding type with cork seals. In what era were the HexagON type (i.e. push the hexagonal end to turn fuel on) introduced? Very clever idea. Some are labelled CMC and others are both CMC and Enots. Who were CMC?

Thanks

Leon

[iansoady]

They were certainly around in the early post-war period as they're mentioned in my early 50s Motorcycles and how to mangle them. My 1931 Sunbeam has the Enots variety fitted although I have no idea whether it's original.

[Rex]

My older brother's 1930s Velo GTP had one too.

[33d6]

Interesting question. I've looked through some 1920's Show Reports and early accessory catalogues and so far have found adverts dating back to the late 20's for concentric taps (Apparently that's what they called them to distinguish them from taper lever taps) but as yet they didn't have the hexagon just a circular disc at each end. The earliest ads were for Tecalemit taps with filter bowl combined.

I then pulled out an early 30's Benton & Stone (Enots) catalogue and it had concentric taps some with two circular discs and one with the hexagon. It also devoted a full page to describing the virtues of the concentric tap of which they had the patent and gave the patent number. I should have written it down but will go back and get it if anyone here can make sense of it.

So far it would appear concentric taps started to appear in the mid-late 20's with the hexagON added a few years later and definitely around by the early 1930's.

Cheers, 

[cardan]

Wow - that's earlier than I would have thought. I was thinking post war...

If there is a patent number I can usually track it down. I wonder if CMC (who-ever they may be) preceded Enots, or came later.

Leon

[BobH]

According to the Enots catalogue of c1938 the concentric tap had been around for 7 years and was patented under #194036/23 in Britain. They state in the literature that the Hexagonal button was for push on and the circular button was push off (something I did not know !!). They came in polished nickel plated finish - Chromium was an extra.

BobH

[cardan]

Brilliant Bob - you've cracked it.

GB194036 was a patent for "An Improved Tap or Cock for use in Combination with Petrol Reservoirs", issued to Sydney Harold Sershall, a resident of Aston, Birmingham, but with no stated connection to any company, in 1923.

No mention of the hexagon at one end, but clearly a sliding tap was available with two round ends during the 1920s.

My guess is that the first taps of this type were not made by Enots (Benton and Stone), but probably by the (unknown to me) company CMC. Later (maybe 1930-ish) Enots became involved and the taps were labelled both CMC and Enots. Later still, but still in the 1930s, the hexagon appeared.

HexagON - get it Bob?

Cheers

Leon

[33d6]

Hi Leon,
Yes, I knew of the hexagON bit before this chatter but what makes me shake my head in frustration is that repro taps are turning up on the market with hexagons at BOTH ends.
Here is a simple but brilliant idea but some repro maker has missed the point entirely. Either that or they are avoiding paying royalties or whatever by making a not quite right copy.
Whatever the case, the mug buyer doesn't quite get what is intended.

Cheers,

[cardan]

Motivated by all the new info, I cleaned up one of the later? taps, which has both "C.M.C." and Enots brands, plus the patent number above. What a lovely object, and much more interesting than the usually-seen repros. Also it has the correct number of hexagons!

The tin I'm delving into had quite a few taps, and I can make a few observations. Almost all of the taps were nickel plated, with only one chrome plated, and a couple in plain brass. The brass ones are old (1950s) no-name brand, so probably just cheap parts originally. Some taps are unbranded, some have the CMC brand, some the brand and the patent number, and some like the one in the photos with Enots, CMC and the patent number.

As 33d6 commented earlier, the name "concentric" was used to describe these taps, and in the 1924 Show number (for the 1925 season) Best and Lloyd exhibited concentric taps, with round ends. It looks like all the concentric taps were licensed under the patent GB194036 at they are all much the same, with variations only in the detail of the pushers.

Anyway, thanks everyone as it's nice to learn something about which I had no ideas at all two days ago.

Cheers

Leon