Of putting the pressure on

28th June 2020

There's been much speculation as to when heritage railways will resume services. Down at the Geoffrey Briddon Building, we just keep plodding along..

We've had a couple of evenings down at the shed this week but really it has been too hot to work during the day. Besides, I had some suppliers to see to collect bits, and find another auction house that I hadn't come across before, specialising in industrial and especially earthmoving plant. Late the previous week I had bid on, and won, a lot comprising a pair of pressure testing machines. I wasn't that bothered, if truth were known, but needed to see how their on-line system worked before trying for a much more interesting lot which Andrew had spotted. For there was a set of 'Weighwell' axle-load measuring equipment going for a low starting bid and would have been a worthwhile asset in determining even-ness of spring loadings on 0-6-0s and such. But Andrew had said not to go over £600, and somebody else was determined to have it: I pushed him or her ('twas just Bidder No...') to over £700 and then gave up. So on Tuesday, having paid for the earlier lot and had it confirmed, I found their base on a former colliery site and spent an hour watching the comings and goings as 10 artics were being loaded with assorted gear. By contrast, my lot arrived in the back of one of those agricultural 4x4s that sound like a cross between a motorbike and a clockwork toy.

Readers with exceptional grasp of detail and retention will now be wondering why I have bought two more pressure testers, and what happened to the one I won on ebay a year or two ago. Well, the sad thing is that the e-bay one was a bit of a pup. I could, had I taken more time, got it going I'm sure, but having stripped it and not being entirely sure how it was supposed to work (comprising one large aluminium block drilled in various directions to form pump and passageways with valves and such therein) its components gradually became separated and I accepted that it was never going to be restored to health, so its various parts have been scrapped. Besides, it was an unknown Birmingham maker (no offence Birmingham) whereas these two are of such respected manufactures as Ridgid and Rotherburger. They are both back at the shed now, after on Wednesday morning, before it got too warm, I topped them up with water at the house and tested them. They both work, which was more than the old one did.

There has been activity on the southern half of Peak Rail this week, as once again using the car park at Darley Dale as their base, contractors took a road-rail machine down to Bridge 35 over the river at Matlock to renew the cross-braces damaged in the floods last year. (They came earlier in the year, but were unable to carry out the work as apparently the current was so strong that the obligatory rescue boat was unable to maintain station.)

There's one of the damaged clamps and new galvanised ones awaiting fitment. Andrew also fitted an evening run to Wetwang to collect a lifting beam off an e-bay sale. He then left it in the back of my van saying it was too heavy for me to unload on my own. He was wrong, but I did have gravity on my side.

Weekend work has largely been concentrated on Ashdown, which, now that the machined items we'd been waiting for have been completed, is being urgently finished off for departure to Shillingstone. You saw the compressor installation last week, the dynamo is now back in place underneath it.

Further down, where the battery box used to be, the AV2 control valve for the vac braking is sited, and the connection thence to the train pipe will shortly be back in place with an isolating cock for good measure. Although the re-location of the batteries is a good thing (the old battery box wasn't the right size to suit modern batteries with the oomph to turn an 8L3) it did reveal some weird and wonderful examples of wiring. How much is Hudswell and how much is Hunslet I don't know, but as the AVR and dynamo and batteries were all concentrated at the front left, yet a 'master switch' is on the back cab wall, it leads to cables whizzing up and down the loco for no really good reason. For example, although the starter motors are to the rear of the engine, and the start button quite close by on the cab bulkhead, the feed passes through a keyswitch to the button, then all the way up front, past the AVR and down into the old battery box where it jointed another wire that travelled all the way back up the other side of the loco to the starter motors. I've identified the feed wire as was from the batteries/dynamo which disappeared up the loco and eventually deduced that the other two red wires in the conduit were out and back to the ammeter - yet the latter seem to be a bigger cross-sectional cable than the aforementioned feed. Logical? Anyway, these little anomalies need sorting out before the loco is handed over and it's a race on to get them off the snag list. Previously when we've done vac fits we have taken one control valve and installed dummy handle and linkage(s). The Hudswell desk does not really lend itself to this: so we're going to do something different.

Remember by using an AV2 we control it by putting air pressure on it and get a self-lapping, fully variable control. Thus it operates much the same way as a loco brake valve and will be easier to control than the centrally-placed dmu valve the loco had when it came to Derbyshire (and on which we skinned our knuckles often because its pipework was too darn close to the brake handwheel!). Elsewhere on Ashdown the belt lengths have been determined, oil pressure gauge re-plumbed, keyswitch changed for one which has a key(!) etc., etc. With a bit of luck it'll be back running again next weekend. And that's about it for the week. Still waiting for a date for the crane to do a bit of rearrangement of the site, especially unloading Thelma and Louise which have been sold and will be leaving shortly. We'll miss their flat loading areas but appreciate the track length recovered!

I'll be back, coughs and sweats aside, next week to let you know how we've got on. See ya then.