Minfit Methodology

The image above is by courtesy of Jonathan Welleans and shows a brace of fitted 16 tonners from detailed Bachmann models, on the erstwhile ‘Wintringham Haven’ layout of Hull MRS.

You might be forgiven for making certain assumptions about vacuum braked  16 tonners; one being that you can run them in more or less equal numbers  to unfitted ones, the other being that unfitted ones are grey and fitted ones are brown.  Not quite …  for most of their lives, the fitted wagons were greatly outnumbered by unfitted wagons, and whilst the odd one certainly wouldn’t be untypical in an unfitted rake, in the early days at least they were generally kept on specific flows.

Only just over 11,000 vac-fitted 16 tonners were originally built, out of a total fleet somewhere around 30 times that figure.  Even by 1970, by which time some later conversions had been added, there were still only around 20,000.   Much later on in their lives, withdrawals really started to reduce the unfitted fleet, and the proportions became gradually reversed, but even as late as 1977, I’d reckon there was still a 2:1 ratio in favour of the unfitted wagons.

Whilst there were a relatively small number of oddballs, experiments and mavericks amongst the fitted fleet, as with the ‘bluffer’s guide’ on Page 108, for the sake of simplicity I’m pretty much going to ignore them here.  So, most of that 20,000 were either of the clasp-braked variety as built, or were from a large batch that were converted to 4-shoe ‘fitted Morton’ pattern in the mid-’60s.  Neither brakegear layout was exactly comparable to its equivalent on merchandise wagons, so a couple of photos should hopefully demystify things.  Like all (well, nearly all) of the pictures on the site, these are clickable for larger sizes and I’d suggest that will be particularly beneficial in the case of the 8-shoe clasp gear:

Note that there are two vacuum cylinders, on the prototype one was slightly smaller but in 4mm scale and tucked away in the shadows, I’m not losing sleep over that.  The more visible parts above are what comes with the legendary Red Panda underframe kit, and careful examination will show where the hand lever has been shortened to cater for the 9 foot wheelbase.

The later conversions referred to were done between 1966 and 1968, and were much simpler, being essentially the addition of a second set of pushrods, vac pipes and cylinders to the existing Morton gear.  Again there are twin vac cylinders, which I believe would have been the norm for these conversions:


Note also two other characteristics of this conversion, one being that almost all of the wagons selected were from batches with the strengthening rib on the hand lever.  The other is that the tiebars are of  ‘L’ section, with the bottom face angling outwards; I actually use ‘T’ section as it gives a slightly more positive key when gluing.

So now you know how to recognise the two fitted gears, you’ll be better able to recognise the impostors, the wagons that were painted brown but weren’t actually vac fitted.  This happened, to a limited extent, for various reasons.  For a few years in the mid-1960s, the grey livery was officially abandoned and various unfitted wagons got themselves turned out in bauxite (or its ‘Freight Brown’ cousin).  If you see a brown Morton-braked wagon before 1966, there’s a chance it’s one of these.  Secondly, and more relevant to some of the RTR offerings, MoT wagons and some of the earliest ones built after Nationalisation were painted in bauxite because they had always been, until the new regime established its own preferences.

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2 responses to “Minfit Methodology

  1. Hi Pennine.
    OK now I’m confused!!! I had it in my head that the morton fitted wagons only had 1 vac cylinder as per the Bachmann model and that the dual vac cylinders and associated changeover levers were only used with the 8 shoe clasp braked wagons. Was there another morton variant as per Bachy and did the dual cylinder mortons have SAB’s thereby negating the need for the changeover levers? Help please!!!!!!!
    Hope you are good and it seems the 26’s have gone too;-)
    Regards
    Mike

    • Hi Mike, good to hear from you. There’s a lot of ‘accepted’ fact when it comes to the Morton fitted wagons converted between 1966-68 and I’m sure a lot of it is repeated at face value – for instance, there are usually said to have been 5,000 conversions yet a Dave Larkin data sheet I have lists nearly 8,500 by their numbers! These little mysteries do catch my imagination and it was my intention for part 3 of the old BRM series to cover vac fitted minerals; obviously that won’t happen now.

      You’ll note I say it’s my belief that they had two vac cylinders, that’s based on looking at a lot of photos of them that show a cylinder whichever side of the wagon you happen to be looking at. Of course, so many pictures only show shadows. I hesitate to sound definitive, but it would seem odd if they’d not all been done the same, and nor do I believe that the cylinder would wander from side to side at random. As far as I know they didn’t have SAB or changeover levers as they were done pretty much on the cheap.

      Having said all that, there were definitely some with only one cylinder but the question is how long they lasted in that state. These would be the B68900-999 batch that ran in brake comparison trials in the 1950s with a batch of Westinghouse-fitted wagons, but later period shots of these all indicate conversion to 8-shoe clasp at some point (probably early/mid ’60s). There are some TOPS lists that show a code for 16 tonners with one cylinder (this is the fourth letter of the code, not shown on the wagon), so it’s possible some of that early batch were never converted, but finding a pic of one is the next holy grail 🙂

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