Of tips and tits

31st May 2020

So I was driving over to Via Gellia (as an eye test) and managed to miss 3 sets of walkers, 2 motorcyclists and 4 other cars on the single carriageway road.

So, here we are again. How to get all this week into a coherent narrative. Let's see. Well, it went up to the wire but Andrew got the new (Mk 3) tips 'finished'. The final pieces though were gas-cut and left loose: this is very much a third attempt. Years ago, before we collected what was then still D2128 from Lydney, we produced a set of ramp rails and for speed machined the end tips at about 35 degrees, thinking the wheels would climb up. They didn't, they simply tried to push them out of the way (and as they were attached to the rest of the ramp and then the trailer you can guess that this was less than what we wanted).

The current Mk1 tips have a much shallower angle, but still the wheels show a preference for going along and not up. The Mk2s worked reasonably well, but I was loading a loco which turned out to have partially seized brakes and a lifeguard still fitted at one side and the tip took the brunt. But along with the Mk3s, Andrew finished manufacturing a replacement Mk2 this last week, so they'll be in use again before long. Anyway, we hadn't time to get the final pieces machined for the Mk3s, and since the angles were still a bit 'suck it and see' he simply gas-cut the pieces for proving purposes and we'll get pucka ones done later. Here's the Mk3 ramps, minus their tips, laid out for gauge checking and a tie bar to set it up.

They will need a dedicated tie bar as the web of the ramp is farther out than a standard rail. I'm colour-coding our tie bars so that we avoid grabbing a wrong one, as happens in the heat of ramp-building.

Up on the front of the trailer the winch was commissioned, but not without trauma. The eagle-eyed may have noticed that the winch rope was visible in the photo of the trailer deck last week - well it was half so, where we had wound it in so far and then stopped. If you think back, we had put together a Lister LV2, but at first it wouldn't go no matter how fiercely we wound the handle, so I ended up getting a new starter motor and after some kerfuffle, Andrew retimed the pumps and it seemed to be better. So we put it up on the trailer neck, hooked up the hydraulics and yippee, we had a working hydraulic winch.

But euphoria didn't last long. The Lister started black smoking and Andrew did some checks and realised we had a pump that was rather too big. So we swapped to a smaller pump and had another go, and started winching in the cable by dragging 2 or 3 wagons back along the siding. This didn't produce black smoke, but I began to notice that white smoke in increasing quantities was emerging from under the rocker cover on one pot. We stopped to investigate further and when we came to start again it wouldn't go at all. In the end we came to the conclusion that this engine needs further investigation, so we swapped it for LV2 number 3 which had come into our hands recently and finished winding the winch rope in with that.

It was all systems go therefore for a loco collection and although a commercial job I'll allow a little peak. The Mk3 ramps/tips did their job, the winch was well in hand hauling the loco on and the tip angle was satisfactory, although the ridges caused by gas-cutting not ideal. A fully machined pair should be fine. The result is below.

I got a bit of time in on RS8 recently. One of the aspects I'm still not happy with is the performance of the brake control. To me a brake control should stay where it is put, and on most locos this is the case. But RS8, with its 4 brake handles and linkages, will only stay put in a fully-applied position or at release. Anywhere else and you have to hold it, which is annoying if you have anything else to do like change direction. In that it is no different to Hunslet locos where the standard 0-8-0/0-6-0/0-4-0 diesel hydraulic had a cam-operated D&M brake valve and if you caught the brake lever accidentally with enough force to start it moving, the lever invariably travelled all the way to release: I know of at least one near-fatal accident as a result.

Anyway RS8 has the same D&M brake valve and the same cam-operation (the same valve can be operated by rotary handle by the way, but a different version) and while it will stay in fully-applied, (I may make up a safety flip-over clip to be sure of keeping it there) the delivered pressure out of the valve is excessive. Years ago I sat down with the then Chief Engineer of D&M in Romiley to discuss train brake installations. He admitted then that this D&M valve has a poor repeatability and for my purposes, he suggested a regulator in its feed to limit its maximum setting. (Westinghouse had a similar installation for one of their straight air brake valves, but to be honest I've never been sure about the regulator - it's either astonishingly reliable or it stops working altogether but the brake valve copes OK without it). RS8 never had such a limiting regulator, so I didn't consider fitting one at Tunstead but recent experience has taught me that that was a mistake, and so a regulator is now in the valve's main air feed, so I can leave the brake controls in fully-applied without fear of the brake pressure creeping up too far.

And while I was in the casings I found a couple of oil leaks that I hopefully sorted. Last year we entertained a family of Great Tits which had nested in the hollow interior of one of the ferry van's buffers. Fortunately they had used the end of the ferry van that we're not coupling things to, and the parents didn't seem too concerned when their home moved up the line 50 yards and then returned. This year we saw the (same?) pair setting up home again, and middle of this week one youngster was at the entrance to the buffer crying out for food. I am no wildife photographer but here's what we could see.

Quite what has happened late this week I'm not sure, because although I saw one of the parents around today, there was no youngster in the buffer and Andrew reported things inside seemed quiet. Has it become a predator-snack? Must get those bird boxes up..

Also recently arrived have been some bits from C F Booths from Greater Anglia stock that was in traffic until earlier this year. Destined for the 2HAP are replacement buckeyes and drawhooks, distributors to replace the triple valves and a couple of new buffers as two of the ones now are in poor condition. Does this mean we are about to get them into running order? No, more a case of grabbing good condition parts while we can. But you never know what might happen next. We had a further discussion on the subject of retention tanks and masserators (well, it's a change from Dominic Cummings - although perhaps a similar theme).

So that's it for this week. Apologies if you came on over the weekend and got back 'file not on this server' messages, we had a glitch but it's all sorted. Hopefully I'll be back next Sunday with more to tell. See ya then.