4561 blog

Let’s get 4561 rolling

11. 4561 Horn bolts wip 4

Having fitted the bolts to 5 sets of horn blocks so far the final 14 bolts are seen here during manufacture. The two on the left have their shanks rough turned and their screw threads cut while their heads have yet to be domed. The remainder have already been done and now await their shanks being turned to finished sizes with the required tolerance to suit their individual holes in the frames.

12. 4561 Expansion link 5 copy

Although we have access to the majority of the original drawings we need for the overhaul, many railway drawings were produced of assemblies. Where specific parts are needed, separate detail drawings of the particular items have to be produced either to ensure clarity in the workshop or to pass to our supplier when parts have to be bought in. An example are the two expansion links which have to be replaced for which the drawing shown here has been produced. This shows the finished product but needs to have some machining allowances added when we have finalised the production process to be used and can place an order.

Work has also started on producing the studs that are required to be fitted in the underside of each horn block and used to secure the horn stays when fitted. These horn stays which are the next items to be machined and fitted, straddle the gaps between each pair of horn blocks to retain the axleboxes in the frames. This will become clearer when we have a photo to show you.

9. 200820 Cylinders loaded plus blokes copy

At around 9.30 on the morning of 20 August Andy Lee (on ground) and his colleague from R&A Transport are looking very pleased with themselves in photo.1 (courtesy Martyn Hughes, Roach Eng.) having just loaded our freshly machined cylinders plus the old cylinder block on to their lorry at Roach Engineering ready for transport to Williton. The old cylinder block is on the LH end. This had been sent to Roach to act as a pattern along with copies of the relevant ex GWR drawings to ensure that all the necessary machining was undertaken of cylinder faces, piston and valve bores and all holes drilled to size and/or tapped as needed.

8. Cylinder blocks arrived (2)

This Photo was taken just after 14.00 the same day in Williton Works yard and shows the two new cylinders which had just been delivered on their pallets on the ground with a rather pleased looking Ryan Pope. He did pass the comment that “they’re here and I am very happy.” The next stages will be to fit the new extension frames together with the cylinders into the locomotive’s main frames in the workshop. At present the boiler for 0-6-0T no.1857 is in the way for doing this so priority has had to be given to completing the re-staying of the firebox backhead and checking that all other work has been completed ready for testing to be carried out preparatory to replacing this boiler on that locomotive’s frames.

10. 200825 Left driving horn bolts fitted copy

Meantime, progress has been made with making the new fitted bolts for the horn blocks. These are the guides within which the locomotive coupled wheel axleboxes are located. The first 28 bolts have enabled the final fitting of the left trailing and left driving wheel horn blocks. Photo.3 (maj) at midday on 25 August shows the 2 LH driving wheel horn blocks assembled in the LH frameplate with 7 bolts driven into each block place with nuts on the inside. One of the RH blocks can be seen through the horn awaiting its new bolts to be fitted. It was planned to compete fitting of the LH horn blocks by close of work the same day. On completion of fitting all 6 horn blocks the next stage is to fit the horn stays preparatory to grinding the working faces true to specific dimensions ready for fitting the axleboxes.

Welcome to our restoring 4561 blog, which in the first instance will document the progress to rolling chassis.  The majority of the work is being done at Williton under the management of Ryan Pope, with external contractors engaged as necessary. The blog is written by Mike Johns, who also lends his valuable experience to the work as it progresses.

200811 4561 Frame assembly

This photo shows the new main frames when work stopped on the locomotive's overhaul. At that time the main section behind the cylinders had been renewed and given a preliminary coat of paint for protection. The parts for the forward section had been trial fitted but awaited completion of the two new cylinders. These had been cast but were stored in Williton yard to weather pending machining in due course.

When work resumed late in 2018 the immediate need was to confirm that the firebox repairs done to the boiler at Buckfastleigh, SDR, were satisfactory prior to completing the remaining work. Sadly some issues were found and some protracted discussions have been necessary to agree a way forward.  The SDR will now provide some replacement parts which will be fitted at Williton who will also complete all outstanding work. This has become possible as a consequence of developing the necessary skills carrying out some boiler contract work for outside parties.

4561 cylinder machining 4

During 2019 arrangements were made to get the new cylinder castings machined by Roach Engineering who had the necessary skills and machinery and recently carried out similar work for other railways. This photo (courtesy Roach Eng.) shows the two freshly machined cylinders as seen when Ryan Pope and Don Wood visited Roach and expressed themselves well satisfied with the quality of the work that had been done. Arrangements were also made to have the new valve liners made and fitted into the cylinder blocks which now await transport back to Williton.

200811 4561 Horn block detail

Owing to the poor condition of the originals it was necessary to renew all the coupled axle horn block castings (12) which are the guides within which the axleboxes are contained in the frames. These have involved initial machining of the basic castings followed by final finishing to size ready for bolting into position. This photo shows one pair of new horn blocks temporarily bolted into position in the LH frame plate. They must be closely fitted to the frameplates, hence the jacks in position in the photo., before the bolt holes can be reamed to final size preparatory to 'fitted' bolts being driven into the holes. The fitting of these bolts is critical as it is important to minimise any possibility of the horn blocks becoming loose once the locomotive re-enters service. Work has just started on making the 84 fitted bolts that are required.

200811 4561 Leading pony truck

This Photo shows the leading pony truck frame which has been thoroughly cleaned ready for a detailed inspection to determine what remedial work may be necessary.

We still need more funds to help with the restoration so please give what you can.