C2 Project News

Mid February 2019

Update from the middle of February 2019 working party

The working party commenced on Friday morning, with Andrew and Dave 1 taking delivery of some steel bars and tools which had been ordered. It was then time to sit down and review some drawings on the computer.
Andrew has been working on the drawing of the front crash beam. This is based on the original Chinese item we have, but reduced in width to match the reduction in width of the front bufferbeam. A good check of the drawings ensured that all the bolt holes would line up with those already existing in the buffer beam.
The tender rear crash beam is very similar, so Andrew copied the front crash beam, and adapted it to fit the rear of the tender. Given that the width of the tender body is largely unchanged, it seems appropriate to keep the rear crash beam the same width as original too. We measured the bolt holes in the tender rear headstock, and added them to the drawing. But they didn't look in proportion when compared with the original Polish drawings we have. It took us a while to work out that our tender has a deeper rear headstock than the Polish drawings show, which explained the different appearance. We're happy to go ahead with the design now that we understand what the differences are.
Paul had given a talk about the C2 Project to the Ffestiniog Railway Bristol Area Group on Thursday evening, so travelled to Wales on Friday morning, arriving just after lunch. He and Andrew took some measurements of the height above rail level of the crash beams on Ffestiniog Railway locomotives. This confirmed that the dimensions which we are proposing are in line with those on existing locomotives, and so will be acceptable.
While Paul still had clean hands, he and Dave 1 reviewed the coupling rod bearing arrangement which Erle had prepared in the previous days. We are now confident that we have a design which, when assembled, will give us all the correct clearances we want, while accommodating the variances caused by wear and tear on the existing components. This means that as soon as we have the material, we can start making the coupling rod bearing covers. It shouldn't be too long now before we can fit the coupling rods.
On Saturday morning, Paul and Dave 1 started to fit the brake weighshaft, before realising that we had forgotten to make the washers which take up excess axial play. Putting the brake weighshaft aside for as moment, attention turned to the brake ratio lever bracket. But we hadn't made the collar to hold the lever on yet. The washers are made of Vesconite (plastic), and the collar from stainless steel, and none of the working party members had experience of turning those materials.
Sometimes the best way to learn is to give it a try, and Dave 1 volunteered to have a go. Having watched others working with stainless steel, he turned up the collar without much difficulty. The manufacture of the Vesconite washers was similarly trouble free. Now we had the missing components, and Dave 1 has learned some new skills.
Dave machines the Vesconite washers.
The two Vesconite washers made by Dave, before assembly.
Brake ratio lever bracket fitted, including the lever, collar and locking nut.
Paul made some adjustments to the brake ratio lever bracket, to align the bolt holes with those in the locomotive frames. Fortunately, a dry run proved that the bottom of the frames are flat enough for the bracket to be bolted directly to it without the need for any further fettling.
Dave 2 and Erle joined the working party on Saturday morning.
The draincock pivot brackets which had been cleaned previously were somewhat worn, so Dave 2 reamed the bores out so that they are now parallel and to a common diameter. Rather interestingly, one of the brackets has numbers stamped into it, which is unusual on Chinese components. We don't know what the numbers mean, but they may give us clues as to the origins of the components. Paul has obtained manufacturing records for C2s in China, and is trying to match up the numbers with drawing numbers, order numbers, or any other numbers that may be recorded.
One of the draincock intermediate weighshaft brackets has numbers stamped into it:


One of the draincock main weighshaft brackets has numbers stamped into it:



Whatever do they mean?
The same draincock main weighshaft bracket also has a number stamped into it in another place:


Extract of the 1966 production statistics from Harbin Forest Machinery Factory, which form part of Paul's collection of old Chinese books and documents. This page lists drawing numbers (of the form C2-##-##) descriptions and production quantities each period. Perhaps we can link some of the numbers stamped into our components with these documents? Or does the presence of the numbers indicate they aren't Chinese at all, but Polish?
Dave 2 also cleaned up the draincocks themselves. We had done the four spares at a previous working party, but the four off the loco were completed too. These all now need lapping in. Dave 2 has a valve lapping tool at home which he has used on petrol engine valves in the past, so he has taken the draincocks back as homework. This should leave us with a good stock of working draincocks including spares - there's nothing more annoying than a passing cock!
Erle continued work on the lubricators, dismantling some of the operating mechanisms, and investigating the seals. He has concluded that some of the seals may be been assembled incorrectly, although others are in a reasonable condition. Paul helped him identify which lubricator is for cylinder oil and which is for bearing oil.
Lubricator - note the bent ratchet handle. Erle Ford.
Lubricator and steam brake parts hanging up after painting. The ratchet handle has been straightened, cleaned and painted - Erle Ford
Lubricator ratchet external view. Black bits will be finished black, while the parts in grey primer will eventually be red. - Erle Ford
Lubricatior ratchet internal view - Erle Ford
Andrew has been working on an as-built drawing of the locomotive frames, in order to capture all the little variations which exist in reality. It will make designing and fitting components easier later. There is nothing worse than coming to fit a piece of equipment, only to find that something is not perfectly straight or not perfectly to size, and the item cannot be fitted. Better to know about those variations first. For the moment, Andrew is focussing on the rear end of the frames, as we would like to start designing a cab floor and its associated support brackets.
With washers and collars now available, Paul and Dave 1 started Sunday by fitting the brake weighshaft and the brake ratio lever bracket, along with its lever. Having carried out dry runs of fitting these components previously, they went on relatively easily. These are the first pieces of the locomotive brakegear to be fitted permanently. Dave 1 went round with a paintbrush later, to apply primer to the bolt heads and nuts, to stop them going rusty.
Brake weighshaft bolted in place, showing the position of the vesconite washers which control its lateral position.
Driver's side of the brake weighshaft. The steam brake cylinder will act on the top of the crank.
Fireman's side of the brake weighshaft.
Using the dimension that Dave 2 had reamed the draincock pivot brackets, Paul sketched up a revised pivot shaft. It's a bit larger in the middle, to account for the wear of the brackets, but the ends are as per drawing where they fit into the levers. Dave 1 then took some steel into the machine shop and started to turn the pivot shafts. One is now well under way, requiring keyways to complete it. It shouldn't take long to turn up the second shaft at a future working party.
The draincock weighshaft also needs to be remade. Because we have reduced the lateral spacing of the cylinders to which the brackets mount, the weighshaft needs to be shorter. Our initial investigations showed that the existing weighshaft is not to the Polish drawings, so Paul is trying to understand why this is. This will allow him to draw up a new, shorter weighshaft, which we can then make.
As it often the case, Sunday afternoon was spent painting things. Erle primed parts of the lubricator operating arm while Dave 2 painted the steam brake cylinders with heat proof paint. It's amazing how much better components look after they've been cleaned and painted!
As a final task, Dave 1 measured the footsteps which are welded onto the front and rear crash beams. He sent his sketch to Andrew, who will add these features to his drawings of the crash beams.
News Archive 
Late January 2019