Early June 2025

With the Railway 200 gala looming large, top priority for the working party was to ensure that the C2 is ready to participate in the event.

The locomotive was stabled in the C2 Shed with its tender in front of the smokebox, as it is easier to work on the cab when the engine and tender are that way round. To restore the locomotive to a conventional arrangement, Dave 1 firstly cleared the cab of the clutter that had accumulated in it. Andrew negotiated use of the Castle Argggg diesel shunter and the raised road in the carriage shed (both were in great demand for moving and inspecting stock for the gala). After Dave 1 and Chris moved wagons off the siding leading to the C2 Shed, Andrew shunted the tender onto 19-Road which has a concrete apron for us to work on. The engine was then shunted from the C2 Shed onto the same road, but stopped a little short of the tender.

Dave 1 lifted the cab floor and removed the drawbar pin. Chris and Andrew then lifted the new drawbar into place. Dave 1 then dropped the pin back into place and restored the cab floor. After Chris had removed the drawbar pin from the tender, it was time to move the tender up to the engine. Some very careful movement of the tender (fortunately it rolls very freely) allowed the drawbar pin to be re-inserted through the tender end of the drawbar.

With the engine and tender now coupled correctly, Andrew shunted the locomotive onto 20-Road (the raised road) so that we could carry out an inspection underneath. Split pins were pushed through the holes in the drawbar pins, so that the latter cannot jump out (highly unlikely, but we aren't taking any chances). In doing so, Andrew found that he could not get the split pin through the pin at the tender end. After extracting the pin with considerable difficulty, he decided to skim 0.25mm of material off the pin with a lathe to make it fit better. We don't mind experimenting with this pin, as it has already been lengthened (by thinning the head) when we discovered the tender dragbox wasn't to drawing. Andrew has subsequently re-drawn the pin so we can make a new one, using the length and diameter we have now determined to be appropriate.

With the locomotive on the raised road, we conducted a careful check of the underside to ensure that all castle nuts and collars are correctly retained with split pins. Once we were satisfied, we invited Jon Whalley (the Ffestiniog and Welsh Highland Railways' Chief Engineer) to inspect the locomotive. We are pleased to say that Jon gave the locomotive a clean bill of health and issued a fitness to run certificate.

It was then time to shunt the locomotive, in its correct formation, back into the C2 Shed to clear 19 and 20-Roads for others to use to carry out wagon inspections.

Back inside the C2 Shed, Dave 2 went round with a grease gun, adding more grease to the roller bearings and tender hornguides. He also filled the temporary lubrication tubs (which currently feed the axleboxes and engine hornguides) with lubricating oil. The locomotive hasn't done a lot of miles since we last lubricated it but that was almost two years ago, so topping up the lubrication system seemed sensible.

After fitting the slidebars at the previous working party, we had measured a skew in the Driver's side slidebar. Dave 1 looked at previous slidebar measurements in our notebooks, and decided that the measuring system we used last time (an engineer's square clamped to the top of the slidebar and an internal micrometer to measure the offset to the cylinder centreline rod) was not as accurate as desirable since the micrometer can easily deflect the long cylinder centreline rod. Earlier measurements had used parallels clamped to the side of the slidebar and feeler gauges, which, when used carefully, can measure the gap between the parallels and the cylinder centreline rod without deflecting the rod. We therefore returned to the earlier measurement system.

The nuts at the front end (where there are clearance holes in the slidebar) were removed. Placing a hydraulic jack between the slidebar and the engine frames allowed the slidebar to be realigned, using feeler gauges to try and determine when the gaps in the measurement set-up at both ends of the slidebar were the same. When we thought we were there, the nuts were replaced and tightened to prevent the slidebar moving again. Dave 1 then took multiple sets of measurements, rotating the cylinder centreline rod by 90 degrees each time to eliminate the effects of any imperfection in the straightness of the rod. The measurements showed that the skew had reduced from about 1.2mm to about 0.3mm over a length of 520mm. Given that there should be 0.75mm of lateral clearance between the crosshead and the slidebar, we are happy that the Driver's side slidebar is now well aligned.

Since the use of feeler gauges seemed to give more reliable results than our previous measurement technique, Dave 1 decided to re-measure the Fireman's side slidebar. This time we didn't try re-aligning the slidebar, as we believed it to be well aligned to start with. The new measurements confirmed this, with a skew of less than 0.1mm over 520mm.

The new set of measurements also provide the lateral offset between the cylinder centreline and the slidebar. Ideally this should be zero, but reality is never 100% perfect. We will use this information to decide the optimum widths of the big and little end bearings on the connecting rods.

We have some M24 castle nuts left over from fitting the engine axlebox keeps, so could fit these to the fitted bolts holding the slidebars to the motion brackets. Dave 2 replaced the conventional nuts with the castle nuts, then used a cobalt drill to create the holes in the fitted bolts for split pins. Andrew found some split pins of suitable diameter, although they were rather long. A few minutes with a hacksaw resulted in correct length split pins which Dave 2 fitted.

Having completed work on the slidebars, Dave 2 applied a coating of wax to them to prevent corrosion.

There are a wide variety of studs used to hold parts onto the crossheads. It would be rather expensive to employ a CNC machining company to make them, given the small quantity of each type. We had therefore decided to make the smaller studs ourselves, and had purchased lengths of 8 and 10 millimetre steel rod.

Andrew cut lengths of rod for the studs, then turned each to the correct length on a lathe. Dave 1 showed him how to use the tailstock of a lathe to start cutting the thread with a die, ensuring the die is perpendicular to the axis of the stud. Andrew then completed threading all the M8 and M10 studs, making a very neat job of them.

Mention of the connecting rods had drawn attention to them. They have been stored in the C2 Shed for many years and were looking rather sad, covered in dirt and corrosion, so Dave 1 decided to clean them. A few hours work with a wire wheel removed the offending contamination. To keep them clean, Daves 1 and 2 gave the connecting rods a thorough clean with white spirit, and then applied primer ready for painting. Although we will probably operate the locomotive with the rods in bare steel finish (protected by a film of oil), until that time we will apply paint to keep the rods from corroding again.

In summary, we achieved the primary objectives of the working party (sorting our the slidebars and getting a fitness to run certificate), as well as carrying out numerous other task which will help towards getting the motion assembled. Rather satisfying really.