Springers are long gone, they were about the largest of the mass producers of narrowboats along with the likes of Liverpool Boats and one or two others, all long gone now
The hey day of mass production was during the 1970's into the early 80's. As the market developed and matured, the emphasis moved from relatively affordable mass produced boats to fairly standard designs towards boats built to order and then finally towards high end bespoke one offs
Today, you won't find anybody mass producing narrowboats, every new build is a one off the the customers precise requirements
BTW, Springers were NOT associated with thin steel as a negative quality issue (although the later 1990's Springers built after Sam Springer passed away did, in common with many other late build mass produced boats, have steel quality problems)
Springer Engineering Ltd employed only Lloyds certified welders and used only the best quality steel. Initially, at least, building boat hulls was a bit of a sideline from their main business of building tanks and pressure vessels
Early Springers were built of 5/16" plate on the bottom (7.93mm), 3/16" steel (4.76mm) on the sides and cabin. A common standard later was 10/6/4 mm (bottom, sides, cabin) although some boats were built with thicker bottom plate (as much as a marketing gimmick as anything)
Legend has it, and we have been assured it's true by an ex-employee, that Sam bought up a load of scrap steel from gasometers and used it to build the early boats. To get rid of the slight curve in the plate, it was laid on the car park and the fork lift truck driven over it repeatedly to flatten it out! The stuff was the best quality steel to start with plus it had been pickled by the gas on the inside and the elements on the outside so it was fairly unwilling to corrode
We can attest to that because when Badger, our 1969 Springer (the oldest known Springer and probably the first hull built by Sam), was surveyed in the late 90's the 3/16" plate was still 3/16" and showed no signs of any corrosion or pitting at all. In fact, the only bit of welding required was on the corners of the counter wear 30 odd years of kicking around the canals had worn the plate down to about a quarter of an inch, a tads thinner than the insurance company insisted on
Ahem ... I can waffle on about this **** for hours and hours, what else would you like to know?
