Steam in Action – An Association Incorporated under Section 21  –  Registration Number 2007/035119/08
www.steam-in-action.com  -  Email : joannewest@btinternet.com

Introduction :

We had a good, productive weekend at the depot, managing to get another one of our steam locomotives off the sick-list and back into operation.  The high focus job of the day was the re-assembly and replacement of the overhauled front bogie for the Class 15CA No.2056 ‘Dorothy’.  The bogie job took a little longer than expected, but apart from the surprise requirement to fabricate some new spacers to go between the compensating spring casting and the bogie frame, the job went quite smoothly.  Quite a few little running maintenance jobs were done on the locomotive on Sunday, as well as the installation of the missing cow catcher, the lamp standards and the front steps.  As I type this paragraph (out of sequence with the rest of the doc), I’ll be heading out to the depot in about 40 minutes to take on the Friday night shift of locomotive minding.  This engine is running tomorrow and Sunday (1 and 2^nd March) and we are hoping that she will do well.

In the meanwhile, Dave Shepherd’s Class 15F No.3052 ‘Avril’ got some attention too, to start knocking off some of the repairs from the list that was written up after her debut revenue earning for Reefsteamers.  The badly leaking power reverser’s lock cylinder was removed, inspected and fitted with brand new seals and a correctly refaced bushing.

The coaches got their share of attention too – a set of brake shoes being replaced and the re-wiring project spreading to another coach.  The bar car got some cosmetic work and a disused refrigerator cavity in the management car’s kitchen is being re-fitted with shelves. 

We had an excellent turn out of volunteers for this Depot Day, and your favourite photographer was run off his feet trying to keep up with the groups scattered all over the Depot, all of them volunteers and all of them working for the love of steam. 

Well done guys … and thank you.

PROJECT : Reassembling and Refitting the front bogie of Class 15CA No.2056

The bogie reassembly and re-fitting job was the glamour job of the day and drew a wide audience, to the extent of being quite difficult for your photographer to get clear, unobstructed shots.  But you can’t get too frustrated with those who have an equivalent interest in steam engines.  But many a time I had a set-up photo ruined by an arm moving into the picture, or somebody’s white helmeted head popping into the view finder.  And clear night time shots with slow shutter speeds are rare opportunities.  Still, here is a sequence of photographs and a write up about how we got the bogie back together.  Normally, when one writes articles, or perhaps a column in a news paper, the difficulties and the hard times make the better stories.  This was a long job with many sub tasks, but it actually went quite smoothly.

The compensating spring casting has already been reassembled by Andrew King and Michael Thiel the previous week, when Michael had just come on duty to do locomotive minding – this thus becoming an evening project.  It gave the bogie team a head start on getting it all back together again, and Michael Thiel got the time to take some care in putting the compensating spring assembly back together again … a welcome change from stoker engine work.  The ‘temper’, leaf count and height of the springs were all verified against a purchased set of scanned SAR drawings.   Every moving point, bearing surface and pivot was well greased and the threads were all cleaned up and re-cut upon assembly.

The day’s Magaliesburg train came back later that evening.  Class 25(NC) No.3472 ‘Elize’ came shuffling in after disgracing herself on the run by breaking a fire grate – a very rare Reefsteamers breakdown.  After the usual locomotive servicing was done, we had a few more people to help put the bogie’s bolster back together.  But getting the wheels and springs back in would be left for the following week, which is the topic of this article.

The long job started with the straightening of the Wheel Stretchers (Compensating Beams) as the RHS set were slightly splayed.  (Pic B01 below)  The stretchers were carried over to the 50 ton press by four people, carefully laid out in the press and blocked up at both ends.  (Pic B02 below)  It wouldn’t do to have this lot flipping and twanging under pressure.  Pressing the wheel stretchers straight was easy enough once a dolly block was found.  Because the ends, made of flimsy 26mm thick steel, are unsupported, it would be only too easy to press them too far inwards.  The correctly sized dolly block was found and the ends of the frame were pressed parallel again.  However, under the pressing, the frame ends bowed in slightly, so with the press extended and clamping the wheel stretchers tight, the hydraulic jack was inserted in the very ends and extended to bring them straight once more.

Oddly enough, only the stretcher on one side was splayed.  It looks as if the engine was driven into an excessively tight curve at one point in her working life.  It took four Reefsteamers doing a dog-trot to get the stretcher back to the bogie frames, (Pic B04 below) which was waiting four tracks down in the eight track workshop, and finally, the assembly could begin.  Assembly started by arranging a set of crude slides for the compensating spring casting.  While the bits were being put together, Phillip Maurer got busy grinding down some detected high spots in the bearing arches on the bogie frame itself.  (Pic B05 below)  As the bogie has been completely dismantled, the original wear patterns will probably not line up with the reassembled components (Even though we marked which ends and which side everything came from) so it’s good practice to get everything smoothed down again.  The slides comprised of four assorted ‘gwala’ bars ramping up to the rail heads and spanning the inspection pit.  The entire compensating spring casting was placed on wooden blocks and resting over the end of the gwala bar ramp – damage to the gleaming new primer-coat paintwork was minimal.  (Pic B06 below)  The assembly was eased up the bars by three people, while two others held the ends of the bars in place. 

With the compensating spring casting precariously in place across the pit under the bogie frame, it was time to sling up and hoist up, before something slipped up!  (Or would that be … slipped down?)  A wrinkle in this job was that the bolster, with the four massive dangling swing links, was already in place above where the compensating spring casting needs to go.  Thus, the sling had to be passed around the entire bolster and down past the sides.  (Pic B07 below)  It puts a bit more stress on the sling and means more corners exposed to chafing.  The cylindrical barrel bearing under the bolster also had to be brought into engagement between the horizontal leaf springs – slightly compressing them.  But the job was achieved and it wasn’t long before the four bolts that hold the casting in place were being screwed in.  Naturally, it’s a two man job with one working from underneath and one working through the bogie frame.  (Pic B08 below)

The wheel stretchers were installed next, with the use of the rolling gantry crane.  They aren’t actually physically attached to the bogie frame – but simply rest in slots.  They are always free to move up and down and very slightly, side to side.  (Pic B09 below)  They were slung into place by using the top pins.  The ends needed guiding and that was probably the most dangerous part of the job – having to watch fingers for nipping.

While the wheel stretchers (compensating beams) were going back in, Dawie was tasked to find some scrap tubing and cut out two new spacer tubes.  You can see a deeply inset bolt hole in the center of Pic B08.  Dawie cut two sections from a scrap super-heater element and machined the ends.  The springs and the shackle bolts were next.  (Pic B11 below)  Each heavy spring had to be slid under the bogie frames sideways and then rotated up in between the plates of the stretcher frame.  Gaining clearance was easy as the stretchers were still free to be hoisted, but the final positioning of the springs required judicious use of the hydraulic jack to get their ends into the shackles.  The ends of the springs, as well as their upper points were all generously lubricated with graphite grease upon re-assembly.  (Pic B12 below)

Meanwhile, fireman Sakkie ‘Sakana’ Kekana got the surprise job of repainting one of the main leaf springs that we had salvaged from the abandoned 15CA out back of the depot.  (Pic B13 below)  The springs had been checked and selected by Andrew King as the closest match for our own.  Luckily, the oxide red primer is quick drying and without fumes either.  While the paint brush was being wielded, the scattered parts of the spring retard straps were brought back together, the four bolts all had threads re-cut and cleaned and the retard straps put back on.  These retard straps serve to retain the leaf spring safely within the frame should a spring or a shackle break or become disengaged.  (Otherwise they’d drop straight into the track work and cause a derailment.)  The job was complicated by the need to leave the now-heavy left spring and wheel stretcher assembly from the compensating spring casting to fit the straps behind the wheel stretchers.  The bolts are also inserted from the inside out (Pic B14 below) which means the bogie frames have to be jacked apart from the wheel stretchers to allow the bolts to be passed in from the interior.  It’s a safety feature as it means the bolts cannot fall out even if the nut on the outside works loose.

Then the work shifted to a new and more exciting phase, the fitting of the bogie’s axles!  Before this could be done, the bearings had to be prepared and fitted.  These big chunks of white metal were brought out of stores and then matched up to each original corner from whence they came.  The oil trays (‘keeps’) were also matched up to their relevant bearing.  Even though the marks matched up, each tray was fitted to its bearing to ensure that they still fitted.  (Pic B15 above)  The white metal from which these components are made can be prone to distortion and burring which might obstruct smooth operation.  Remember that the oil trays are usually installed or removed from under the locomotive during a service, and with the packing, or socks, restricting the movement as well.  One wants the movement to be as free as possible.  The two bearings for the front axle were anointed, by hand, with fresh MH oil.  (Pic B16 below.)

There is a bit of errata required here, as pointed out by Shaun.  In a previous Depot Report I stated that lubrication oil flows down from the thrust face into the bearing arch.  It actually moves up and out from the bearing arch to the thrust faces that bear against the back of the wheels.  The oil is pumped up those oil galleries by the hydrodynamic pressure of the oil between the axle and the bearing arch – thus, the oil in the tray also constantly lubricates the thrust faces.  The upwards flowing hydrodynamic action is exactly the same, in principle, to that of a ‘rifle bored’ con-rod in an internal combustion engine, where oil is automatically pumped from the big end to the gudgeon pin.

Okay, errata over and back to the show.  With the bearings well oiled, and the corresponding surfaces on the axles well seasoned, they were loosely placed on the axles.  Meanwhile a pair of freshly made packing bags, what we call ‘socks’, were inserted into each cleaned tray and drizzled with a generous, yummy coating of MH oil, even through the socks were already impregnated with oil.  In fact, on the following day, the trays were withdrawn once more and even more oil poured in. 

The oil trays, or ‘keeps’ as we call them, were put in their slots in the bearings.  In normal circumstances, this can be tricky as you’re duck walking and grunting under the locomotive.  There was still much grunting involved even though the axles are loose and there weren’t even frames to obstruct movements.  (Pic B18 above)  The new socks are tightly packed and put up a bit of a fight.  Incidentally, this illustrates a weak point in this type of design for a bogie bearing.  When repacking these bearings in service, any dirt on the axle ends would be wiped off by the oil socks and introduced into the very bearing surfaces that you’re trying to lubricate. 

The top of the axle bearings incorporates an oil chamber that is normally hidden under a thin pressed steel cover.  The chamber uses six trimmings (‘or wicks’) as per the oil pots on the motion.  4 of the wicks provide oil to the axle horn bearings.  Piet Steenkamp is the ‘trim master’ of Reefsteamers.  He had fabricated and pre-soaked the trimmings in paraffin to ‘prime’ the capillary action of the fibres.  (Pic B19 below)  Just like the oil pots on the motion and valve gear, these wicks are immersed in MH oil.  The semi circular bearing pads for the tips of the wheel stretchers were inserted as well (Pic B20 below) and then the all important oil was added.  (Pic B21 below).

The next step is to put the back covers on, with the studs being carefully wire locked – it’s not done to have parts just dropping off under the engine.  (Pic B23 below)  With the bearing assembly and oiling work all done, it was now time to use the rolling hoist to left up the bogie frame end and to roll the axle in between the horns.  There was some debate about the weight capacity of the hoist – but as Andrew had safely dismantled this lot using the same equipment, all by himself over Christmas weekend, we got on with it.  (Pic B24 below)  Rolling the axle on the rails isn’t at all difficult, but the bearings have to be kept upright when they try to revolve as well. 

We lowered the hoist very gently and fed the bearing slides into the waiting (and freshly lubricated) axle horn guides.  The oil chamber covers were quickly slipped in under the descending wheel stretcher ends.  (Pic B25 below)  That was one axle done and all the work had to be done on the rear axle and its two bearings.  The second axle’s work was enlivened by the fact that it was stored out on road 7 in the depot and still had to be rolled along the trolley tracks, manually grunted 90 degrees and then trundled along the length of the depot and then turned 90 degrees again to line up with ‘our’ bogie.  It now has got some fresh scratches on the flanges!  The rolling gantry came in useful to hoist the trailing axle and pass it over the bogie assembly.  (Pic B26 below)  There wasn’t enough travel available in the hoist to clear the axle completely, and it had to be held labourously off to one side to allow the two sets of wheels into interleave past each other.  But once the axle was safely down on the rails again, it was time to start the bearing assembly procedure all over again.

But there was a simultaneously annoying and amusing hiccup in the job.  The team had forgotten to put the retaining bolts in for the cotters for the lower set of links on the swing links.  And these are very hard to get at on an assembled bogie.  (Pic B27 below)  There wasn’t enough room to apply a spanner or a socket to the nut end.  We all had no choice but to stand around and watch the alternative cursing and laugher going on – but hey, at least it was remembered. 

Well, with the bogie finished, Class 15CA No.2056 ‘Dorothy’ still had to be prepared to accept this mechanical work of art.  The kingpin and the lubrication pipes were inspected.  You can see the general layout in Pic B28 below.  There are four oil pipes that are filled from a common oil-box on the front snuffler plate.  Each pipe discharges above the location of the four swing link pins.  The center pipe discharges into the hollow pivot pin and eventually discharges into the pivot boss.  The pipes were straightened up, blown through with compressed air and rodded through with heavy duty baling wire.  The four swing link oil pipes were actually functioning as evidenced by the nice oily swing links discovered upon removal, but it’s always good to take the opportunity to get the ‘kidney stones’ out of the plumbing when one has free access like this.

The center oil pipe was a problem.  It discharges into an open top bore which had filled up with grit and sludge.  The bore discharges by gravity through a sprout and drips directly into the swivel disks.  Of course, this bore was just about totally blocked.  Shaun and Dawie spent about 30 minutes cleaning out the gunk from the chamber, working through the very limited space you can see above the square base plate in Pic B28.  The copper pipe should have been pushed further in, and then the hollow chamber filled with clean woolen waste around and above the copper pipe – to act as a barrier against further dirt 

While the dirt picking was going on, Sakkie cleaned and lightly oiled the bolster bearing disks.  (Pic B30 above)

Jacking up the locomotive was the next task – a bit nerve wracking to watch and in which to participate.  I hid behind the camera tripod for protection.  Actually, the jacking operation was performed safely and worked well.  We started from the position shown in Pic 31 below.  The locomotive was jacked up with pneumatic jacks under the buffer beam, with a collection of the ubiquitous wooden blocks shoved and shoved in the expanding gap.  The jacks were put through two full cycles, being withdrawn halfway, their rams retracted and starting their cycle again mounted on their own wooden blocks.  Great care was taken to jack up both sides evenly.  The final height had the lowest edge of the buffer beam 1.2 meters from the ground – as assessed by me making a nervous measurement.  (Pic B32 below)

Before the bogie was reinstalled, advantage was taken of the ‘loose tooth’ wheel-less gap between the cylinders to get some Reefsteamers under there and tighten up some bolts on the draft gear and the buffer spring casings – some of which were found to be loose. 

The bogie was wheeled in (Pic B33 above) and the front gap packed up again with wooden blocks in case a jack slipped.  The engine was then carefully lowered to engage the bolster pin into its socket.  Andrew King was at home in that small space putting in the locking pin, which was held in place with wires (Pic B34 below), which Shaun Ackerman was holding under tension.  (Pic B35 below)  It looked like he was using dental floss on the Iron Giant.  Andrew had to get under that decreasing gap and give the suspended bolster a nudge on its swing links to get everything to line up.  In spite of Shaun’s hands getting some deep groves and Andrew bumping his nut a few times on the lowering frames, the installation went well.  The bogie boys were quite quick to break up at about 8:30pm although 6 of the die-hards decided to go out for a celebratory supper.

This engine was worked on some more on the following day and here is a list of what was done :

1).   The bogie horn keeps were fitted.

2).   The axle box keeps were removed again and re-filled with oil,
      just to be sure of good lubrication, as the woolen oil socks soak up the oil.

3).   The ejector cone caps where removed, faced in the lathe and re-fitted for a better seal.

4).   The Bissell and Tender axle box covers were removed to check the oil,
      all the socks were turned and the boxes refilled with fresh MH oil.

5).   All the fusible plugs were removed from the firebox, re-melted and
      cleaned and then re-cast before inspection, recording and re-fitment.

6).   All the oil trimmings have been replaced.

7).   The cow catcher was reinstalled.

8). The lamp stanchions were remounted.

9). The smoke box front braces were replaced.

10). The front steps were refitted.

PROJECT : Conducting a boiler test on Class 15F No.3016 ‘Gerda’ :

Today’s boiler related work was the third installment in a three week saga.  Actually, the boiler wasn’t tested on Saturday, but rather, on Sunday.  Saturday’s work was the removing of a leaking siphon tube plug located in a classically awkward location.  It is a plug on the firebox front wrapper plate (Sometimes called, The ‘Throat Plate’), right in the middle and hidden between the cylindrical boiler barrel and the frames.  It is where the belly button would be if a locomotive boiler had one.  Removing these plugs isn’t difficult on a regularly run and serviced locomotive (aka, frequent boiler washouts), just so long as one has room to use a Tommy bar of some kind for extra leverage.  This plug, usually the rustiest plug on a steam locomotive, had little no ‘swing room’ for a Tommy bar of any kind.  You can see the position of this somewhat rusty ‘belly button’ in Pic W01 below.  You can see that there isn’t much room to work between the locomotive frames and the objects in the front and the rear are the main springs and the spring hangers or the rear driver axle.

A locomotive boiler, firebox and the back plate is usually fitted with tapered plugs with square heads, on about 2 – 2 ½ inches along one flat.  The threads are of heavy gauge but can wear out over the average 50-80 year lifespan that we expect as normal in the 21^st century.  These plugs, scattered all over the locomotive, are removed for boiler inspections, and more frequently, for boiler washout.  Some of the holes are used as rather sludgy drain holes and others are used to allow the ingress of water hoses and hot water or steam lances.  The siphon tube plugs are used to de-scale and inspect the siphon tubes that span the firebox under the fire arch.  The plug heads come in various sizes, so a part of the challenge is finding the right 80 year old tube spanner to fit the right 80 year old washout plug.  The tube spanners usually only have 2 bores drilled at 90 degrees in their drive barrels, (Pic W02 below) so, if you can’t latch onto your square-head and turn it at least 90 degrees in the arc of one swing, you can’t latch on for a further swing.  We have some curved pinch bars and crow bars for this purpose.  (By contrast, a classic motor mechanic’s crescent spanner has a head that can be offset by merely 15 degrees if you flip the head over.)

A Tommy bar was duly found, with the usual engineering pay-off (aka … conflict) between the long length for good leverage, versus the access.  Because of the cramped spacing around the rear drivers of this engine (Pic W03 above), only one person could get a good grip.  These boiler washout and other plugs usually have shallow heads in relation to the size of the square, so, even with one person putting all their strength into holding the tube socket n place, if you tilt the Tommy bar, off it comes.

Reefsteamers are nothing if not inventive, and the block n’ tackle was soon brought out.  Dawie Viljoen was dispatched to find a boiler tube to fit over the Tommy bar, and the tackle’s hook was put into the open end (Pic W04 below), while the hoist hook was hooked around a gwala bar wedged through the frames.  (Pic W05 below)  It took a while to untangle the chains but they got the contraption set up.  Phillip is a natural with dangling chains, for, working as an electric freight driver in Switzerland, surely he’s had ample experience in resetting the chains on Swiss cuckoo clocks?

The hoist set-up was a failure.  We were able to put several fellows on the hoist chain, although only one at a time could apply his weight while the others were restricted to biceps power only.  But with the leverage, the boiler tube just bent in the middle with a loud pop and the siphon tube plug was as stubborn as ever.  And it put up another bit of a fight after a minute or two of discussion.  Phillip was squatting on his hams when the stowed hoist slipped and the hook set came down and bopped him right on the head.  His mandatory Reefsteamers hard hat saved him from no more than a shock – but it was a graphic illustration of how quickly an accident can happen in this rather rough environment.

Well, we were bending boiler tubes and couldn’t fit any longer Tommy bars.  The weapon of last resort was brought out, the infamous acetylene torch.  With the tube sockets, Tommy bars and chief engineers cleared away from between the frames, the torch was played onto that siphon tube plug from the left side of the engine.  (Because there’s a better walkway that side and it’s easier to trundle the heavy cylinder trolley there.)  It was quite a reach, you can see Shaun working at full length, and wrong armed in Pic W06, but luckily with a convenient spring upon which to rest and steady himself.  Compactly built Andrew ‘Noddy’ King was able to fit in the gap between the frames – by squatting on top of the brake rodding, but the rest of us are too tall to do this with safety, with a hot flame close by.

With the plug just starting to glow, it was quenched with cold hose water to quickly contract it.  It made a lot of steam, which looked eerie wafting up from under the boiler barrel.  (Pic W07 and W08)  As it turned out, it only needed one heating cycle to crack the ‘grip’.  The guys needed to put a Tommy bar and a tube socket back on.  They went for a shorter tube socket this time, but this meant that the stainless steel boiler band had to be loosened slightly and knocked forward to clear the work space.  (Pic W09 below)

But this was the end of the battle and the stupid plug came out slowly with a 2 foot Tommy bar fed in alternatively from either side of the engine to get enough swing in under the boiler barrel and over the frames.  You can see the mark of success in Pic W10 below.  Andrew got on with cleaning the plug before running the thread clear with a tapered die.  The initial scale came off with the wire brush wheel. (Pic W11 below)  Andrew eventually scraped out the valley corrosion with a chasing tool.  (Pic W12 below)  This gritty stuff would have come out with a taper tap – but would be likely to jam and cause wear in both the work piece and the tap.

The boiler has been under work for four weeks to get it to this stage, including some week-day button-up work courtesy of the pensioners.  When prepping a steam locomotive boiler for a boiler test, one has to either remove or block up any of the typical leak points as not to cause an incidental drop in the test gauge pressure.  Aiden Mc. Carthy, with some assistance from Lee Gates, conducted the first boiler test.  The first job is always to remove one of the foundation ring washout plugs let the residual water drain from the boiler, and insert the test coupling.  This in an interesting contraption as it uses a bleed valve to help modulate the pressure.  (Pic W13 below)  Under conditions of high pressure and low water flow, the throttling effect of a valve is much reduced.  The main valve is a plug valve, which isn’t a good design for throttling anyway.  The bleed valve is a gate valve. 

This Class 15F’s boiler had already been prepared for testing by the pensioners (who we call ‘The Spoories’) crews during the weeks.  Both of the water gauge columns had been removed and blanked off.  All three safety valves had been removed and blanked.  The two blow down valves were positively sealed with a plate-backed rubber plate and the regulator’s (‘Throttle’) four multi-valves and the pilot valve were all ground in and temporarily sealed.  The ‘Turret Valve’, the steam locomotive’s ‘main switch’ for all the steam operated equipment, was also ground in and shut down tight within the turret manifold.

We had a conveniently located and functioning fire hydrant to top the empty boiler up – rather than wasting half a day filling up the boiler with a conventional hose pipe running through an open washout plug.  Even so, Aiden had to sit and wait for the metallic, echoing splashing to stop, while I buggered off with the camera to catch pics of the other work teams doing their stuff.  (Pic W14 above)  We can tell that the boiler is full when water starts running from the overflow pipe that runs from the safety valve pads.  There was some confusion with the plug type vent valve at the head of the vent pipe.  (Pic W15 above)  It works opposite to the usual standard – the valve is open with the handle 90 degrees to the pipe.  (Normally this indicates the valve is closed.)  The first test up to water mains pressure was a failure.  I couldn’t hear anything (Only having effective 35-40% hearing and my stupid 24/7 tinnitus often sounds like a mixture of escaping steam and the staccato hissing of a clapped-out surface discharge toilet cistern topping off – which masks any hissing I might have heard), but Aiden could clearly hear water squirting somewhere under pressure – exactly what one DOESN’T want to hear when pressurizing a boiler.  It turns out that the boiler wash-out crew hadn’t fully tightened up the washout and siphon tube plugs in the back plate and water was squirting right through into the cab. 

Bad Spoories! 

Well, if one plug is loose, they probably all are.  Aiden and myself worked patiently all around the cab and the firebox, tightening up the plugs.  But we had a problem in that the boiler surfaces, the cladding and the packing were already well soaked from our premature failed test and it would be hard to see any genuine new leaks after the plugs had been properly tightened.  And a cold boiler takes a while to dry off.  We conducted three water mains pressure tests during the day and although there was an improvement in the ability of the boiler to retain pressure, the boiler couldn’t hold the kPA.  The left hand clack started leaking with the slightly higher pressure and had to be ground in, as well as the take-off valve (Pic W18).  The center siphon tube plug on the front wrapper plate was known to be leaking, and there was an unseen leak in the upper left firebox, possibly under the cladding.  That’s bad news as it usually means that a boiler stay has broken, or a stay rivet has corroded.  But as everything was already wet or damp, it was hard to tell for sure. 

Lee Gates and Andrew King did the next round of boiler tests two weeks later.  The water mains pressure, which is quite variable at out depot, was reasonably good today and we got the boiler up to 1000Kpa on occasion.  Nothing went bang.  We focused on the boiler itself, which had dried out over the two previous weeks, and Lee was put to the task of getting the boiler properly buttoned up while Andrew used both his eyes and his ears to check for leakage.  Andrew uses a piece of chalk to mark a cross on suspect plugs and that cross is only eventually removed once the plug is certified dry and non-leaking.  Most of the boiler plugs are fairly easy, but the three plugs on the under belly are two man jobs as one fellow needs to hold the tube socket.  If you drop it, it falls right through the frames and into the inspection pit ... a real schlep to have to duck-walk under the engine every time you drop the works!  The various cab plugs were dry but we nipped them up ’for luck’ anyway.

Three stubborn leaks were found up on top.  The washout plug right behind the safety valve mounting pad just wouldn’t stop weeping.  A rivet was leaking under the right front safety valve and the pressure gauge shut-off valve was leaking through the gland.  (The pressure gauge has its own valve so it still indicates boiler pressure even when the turret is shut down.)

The safety valve pad leak was solved over several sessions of judicious tapping with a flat ended drift, to peen the large recessed rivet over into its gap.  The washout plug was another story.  Even after tightening up it still wept.  We even used PFTE plumbers tape on the taper to try and prevent the water creeping up the threads.  It helped, but we still had a stubborn bubbling.  The pressure gauge shutoff valve was a problem too, with the leak worsening under tightening of the gland nut.  But we just knocked the valve all the way shut and the leak stopped.  Good enough for a boiler test but one has to remember to switch it back on again!  It’s surprisingly comfy sitting cross legged up on top of the boiler, with the turret manifold to your back and the safety valve pads to the front, and the characteristic insulated turret feed pipes very conveniently one to either side for foot rests or hand holds. 

The water mains pressure suddenly failed in the afternoon (I won’t repeat Andrew’s swear words) and the pressurized boiler started discharging back into the water mains during the afternoon test.  So we coupled up the WAP pump and got the boiler up to 1600kPA and holding.  It still leaked very slightly, but that was known and estimated to be the siphon tube plug on the front wrapper plate (featured in the article) so we’d made progress.

On the day following the removal and replacement of the stubborn siphon tube plug, the boiler was buttoned back up and run up to the 125% operating pressure as required for boiler testing.  No leaks were found.  The boiler was officially hydraulically tested and passed on that score – but the visual inspection came up with some potential problems. The back firebox corners are suspect – but they will be closely examined and ultra-sounded to check for thickness within a week.  While the inspector is present, the front corners and the throat plate will be checked as well.  If we have to take the engine out of service to fix the firebox, so be it – but it means she won’t be running for the Free State Explorer. 

SIA PROJECT : Class 15F No.3052 ‘Avril’ Reverser Repair :

Aidan Mc. Carthy got assigned to this one, a quiet job working by all by himself in the Top Shed.  Those who are following our (mis)adventures will remember that we ran Class 15F No.3052 ‘Avril’ for her first revenue earning trip for Steam in Action three weeks ago.  She ran very well, as allowed by the deadly combination of poor quality coal and a failed grate shaker.  But a number of problems became apparent.  The power reverser was one of those problems– as it lost much of its damping oil on the Magaliesburg run and had to be refilled several times.  We knew it was leaking but the severity of the leak surprised us once we were out on the line. 

But first, a bit of background.  The typical SAR power reverser is basically a steam-powered linear servo motor with damping and a hydraulic lock mechanism.  It consists of a pair of cylinders (of equal ‘stroke’, or length) which are linked together by a common piston rod.  One cylinder (front) is a steam cylinder that contains a double acting steam piston that can have steam applied to either one of its faces to move it to one end or the other to power-shift the valve motion.  It is directly connected to a similarly sized ‘lock’ cylinder that is totally full of oil at both ends.  Both ends of the lock cylinder’s cylinder are connected by what is known as a ‘cataract valve’.  As the power cylinder’s piston moves, the common piston rod moves, which tries to push or pull the lock cylinder’s piston through the oil.  With the resulting pumping action, the oil is bled from one end of the lock cylinder to the other means of the open centrally-mounted ‘Cataract Valve.’  The restriction of the viscous oil flow through the valve’s ports acts as a drag on the power cylinder and slows the valve motion movement down to a controllable speed.  It’s a similar methodology to a car’s spring damper, or a traditional hydraulic door closer.  If the centrally mounted ‘Cataract Valve’ is closed – no oil can flow from either end of the lock cylinder to the other.  The incompressible oil trapped on both sides of the lock cylinder’s buckets hold its piston rigidly in place, which, via the common piston rod, holds the power cylinder’s piston in the desired position, and thus keeps the locomotive in the correct selected cut-off.  (or ‘gear’)

R00 – A general layout of a ‘Hadfield’ reverser with the front of the locomotive to the right.  The green cylinder is the hydraulic lock cylinder, crowned by the cataract valve.  The red cylinder is the double ended power cylinder, topped by the black steam valve, the thin live-steam supply line coming in from the right, and the cylindrical brass displacement lubricator on top.  The long red bar is the front reverser lever, while the long green bar is the indicator lever that operates the pointer on the reverser quadrant, back in the cab.  Notice the two cylinders are coupled together by a common rod.  The leak was at the extreme left, behind the copper boiler feed pipe

Without a functioning lock cylinder, ‘Avril’s’ power reverser kept creeping to full forward gear.  (Equivalent to 1^st gear in a road vehicle)  The actuating (power) cylinder, without the braking and damping effect of the oil within the lock cylinder, reacted too fast and kept over-shooting the driver’s cut-off settings.  In fact it tended to slam to either full forward or full reverse with little control in-between.  The crew had a very interesting run to and from Magaliesburg!

And the poor old engine ended up in a bit of a mess.  (Pic R01 below)  I spoke of this as being a ‘debut run’.  ‘Avril’ reminded me of a matriculant school girl, who’s spent hours getting all dolled up for her graduation dance … only to spill a big sloppy chocolate cream éclair down her beautiful silken gown, on her big night.

Chief Engineer Andrew King already had his suspicions about the cause of the leak, which turned out to be 100% on the money – but there was also another unexpected problem uncovered, which even his magnificent mind didn’t come up with.  Aiden Mc. Carthy’s job started simply enough with unbolting the end of the cylinder with car-sized ring spanners.  That glistening green oil left over from the trip amply demonstrates the logic behind the SAR tradition of painting the lock cylinders and the indicator linkages green – it matches!  (Although, you can see by the worn paint that No.3052 ‘Avril’s’ lock-linkages were originally painted blue.) 

Because the end of the piston rod isn’t belled or obstructed, it wasn’t necessary to dismantle the glands or the seals to get the assembly off.  You can see the cover half-pulled in Pic R02 above.  This was Aidan’s first challenge of the day, as the cover wouldn’t come off past the wide bore boiler feed pipe.  This is one of the two characteristic diagonal copper pipes that one sees climbing up the sides of the boiler to top-mounted clack valves on nearly every SAR steam locomotive.  And the lower bend (Pic R02 above) was in the way.

This seems like bad design (and it is) – and it actually is more a result of standardized placements being mixed with part-placement unique to a class of locomotive. But normally the lock cylinder’s cover doesn’t have to be removed to change the seals.  Remember that we didn’t know for sure what was causing the leak so everything had to come off.  Aiden had to do a bit of ‘slogging’ with a mallet against a round handled ‘slogging’ spanner to ‘break off’ the over-sized nut before using the spanner manually.  (Pic R03 above)  We could hear him from the club house!  Aidan then loosened the top nut at the clack valve and tried to rotate the pipe to get the bend.  It was close, but as often happens with steam locomotives, ‘close’ just isn’t good enough.  The boiler feed pipe had to come off and Andrew King was called in to help with the removal.  The pipe actually ‘popped’ out of the clack valve with a bit of 2 foot crowbar action.  (It was a LOT harder to get it back in again.)

They then dismantled the valve packing and Andrew’s original suspicion was proved.  There’s a brass bush at the outer end of the seal stack and it is usually machined tapered for an asbestos rope seal and flat for more modern ‘Chevron’ seals.  We had the older style tapered bush running with new seals.  But the surprise problem was that the seals themselves had been installed back to front.  Most bearing and shaft seals run with the smooth or convex side facing the medium to be sealed, and the grooved or concave side facing the external area.  Chevron seals work the opposite way – and it would be natural, if one doesn’t know any better, to place them rounded ends facing the entrained oil.  Chevron seals use a tapered outer ring which is quite flexible.  As the pressure builds up behind the seal, the oil pushes against the concave side, behind the chevron.  The effect is like holding an umbrella upside down and filling it with water – the dome of the umbrella will tend to become wider in diameter.  The angled chevron thus tries to straighten out and the effect is that the seal expands in diameter and creates a tighter seal when under pressure.  There are 5 seals in this pack, each one sealing the bit of leakage from the one behind it. 

But if the seals placed back to front, as these were, the pressure of the oil closes the outer angled ring, closing the chevron and making the seal effectively smaller in diameter.  The oil leaks past the bearings with ease.  With a slight vacuum in the cylinder now, if the piston moves the other way, the chevrons open up with atmospheric pressure and block the leaked oil moving back into the cylinder from the gland packing cavities.  In effect, the reversed chevron seals act like the one-way valves in a very slow pump.  The engine literally and positively pumps oil from the lock cylinder every time the reverser lever is operated and returned.

The outer seals in the stack had been damaged by running backwards against the taped bush.  The new seals come in sets of five (Pic R04 above) and it is false economy to change just one or two of the disks.  So the entire set was replaced.  They were found to be too large in diameter and had to have slots very carefully cut out of them.  The gap had to be such that it would close up with a very slight overhang within the gland cavity – with no leaks, but also with minimal overlap as not to affect the operation of the neighbouring valve rings. 

James Thomson was put to the task of machining the outer bush flat, to suit the new chevron seals.  (Pic R06 above.)  After centering the bush in the chuck, the entire job only took him a few minutes, as the length of the bush isn’t critical.  (It is pulled down by the gland packing cap anyway.)  The gland packing cap was found to be a bit bent, so James and Juan had a go a flattening it in the 50 ton press.  (Pic R07 below)  They weren’t successful so they tried to spring the plate straight with a bit of mallet action.  Juan ‘Nippies’ Buys looked as skeptical as I felt (Pic R08 below), but he managed to spring the plate out somewhat straighter. 

James Thompson then got busy cutting out the gasket material with a heavy duty pair of tin snips.  (Pic R09 above)  We needed a new gasket for the lock cylinder’s end cover as the old one broke apart upon removal.  We Reefsteamers generally replace or re-fabricate gaskets upon removal anyway, and copper ring gaskets are re-annealed as a workshop standard.  The blades on the first pair of snips kept spreading on the pivot as this material is tough, impregnated fibre-based sheet and isn’t rubber as it appears.  The inner and outer edges of the gasket were trimmed with the snips instead of the hammer, as we normally do,, as the inner raised surface is too shallow to present a decent corner with which to tap-cut the gasket.  But the holes were easily accessible to the ball peen (Pic R10 below) and James got to use his tapered awl too, making a really neat job of those holes.

With the gasket prepared and ready, Aiden wiped out the inside of the cylinder and scraped the dead gasket from the sealing surfaces.  The cover went back on easily and with care to tighten the nuts in diagonal sequence.  (Pic R12 above)  Aiden used a 26mm spanner, which is a miniature nut by steam locomotive standards.  The inner ‘top-hat’ bush is already in place in Pic R12, and the seals were assembled after the cover was tightened.  Each individual seal had to be rotated to stagger the slots and its edges carefully fed into the bore to prevent crimping and tearing.  With the gland cover loosely snugged up, two seals were still outside their cavity.   (Pic R13 below)  Aiden had to take a lot of care to get those seals in straight and untorn.

The seals and the cover went back on with little trouble, but the boiler feed pipe was another story altogether.  A 2 ½ inch copper pipe is surprisingly unyielding!  After various combinations of Lee, Aiden and Andrew trying to get that pipe in – we sourced two crow bars and levered the pipe simultaneously at both ends.  (Pic R14 above)  It was quite a wrestle but eventually the magic angle was discovered and the stupid pipe just popped straight back in.  The cylinder was left empty but will undergo testing at the next boil-up, especially as the seals may need to be nipped up a bit more once they’re under pressure.

SIA PROJECT : GMAM Garratt No.4079 ‘Lyndie Lou’ Stoker rebuild : Tested!!

I wasn’t at the depot on Sunday, (Had office work to do at home … bleh!)  A small team of Reefsteamers were at work, putting the front end of the Class 15CA together, and checking out the GMAM stoker.  The crankcase was refilled with heavy weight motor oil (20W 50) as for older car engines.  The intake ducting was hooked up to compressed air and the motor run under pressure.  The newly overhauled two cylinder double acting steam engine is reported as running very smoothly.  It has been passed for refitting into the waiting arms of the big green machine that is bolted between the two brass ‘Lyndie Lou’ nameplates.

The test team members were careful to lubricate the engine with MH oil poured through the intake before starting up with compressed air.  (Only the crankshaft, its bearings, the big ends and the valve eccentrics are lubricated by the entrained oil – the valve spindles and the pistons are lubricated by steam-bourne oil.)  A bench tested mechanical stoker motor has the same problem as a dead steam engine in tow – the hydrostatic lubrication system isn’t available  A mechanically lubricated locomotive, such as our Class 25NC and the Sandstone Estates GMAM Garrett, has an easier time of it as the mechanic rods are still worked from the eccentric crank.  But in cold temperatures, the oil would tend to gel in the tank and not feed into the pump’s cylinders. 

Our focus now is on getting our mechanically stoked Class 15F’s (No.3016 Gerda’ and No. 3052 ‘Avril’) in tip-top condition for our coming tour.  But the new axle bearings and the overhauled stoker motor are ready and waiting to go into the Garratt. 

Shaun Ackerman is pleased with the work and this is what he has to say….

The mechanical stoker engine is brand new and will run well for many years to come,      
once again the quality work that Reefsteamers and its members deliver all the time.

PROJECT : Coach Repairs

Coach work continued with Fred Sewell doing the electrical work, and our two coach restorers keeping themselves very busy in the kitchen of No.42, the Management Car, as well as hanging pictures in the bar car.  Meanwhile, the Mathee and Son axle greasing team were on the job.

Fred’s coach work was the opening and the stripping of the old light fittings within the compartments of the Sleeper Coach No.23345.  The old lamps were actually intact and working, but were low voltage units running from heavy transformers stashed in the incomer panels.  As mentioned previously, the coaches are through wired for 220V, primarily for the water pumps, bar car and kitchen fixtures.  Now the lamps are gradually being wired to run from the mains voltage as well.  One feature that will unfortunately be hard to replicate are the low wattage night lights that are fitted to the sleeper lamps.  (Pic C01 below)

Fred Sewell had a rough day of it, working in a hot coach with nary a breeze wafting through the windows.  He was in pain too, his recent kidney tumour operation site playing up after getting pulled from sitting too long during the week – and he wasn’t able to last the entire day.  However, we have another coach that is switching over to the reliable and brighter 200V supply, eliminating troublesome transformers and inverters. 

The Wehmeyer brothers started their day with the usual latch, handle and hinge work.  But you could tell by the spread of tools laid out in the walkways that they had something more involved in their collective minds.  (Pic C02 above)  The more involved work was that of mounting pictures on the paneled wall behind the bar.  We’ve already had decorative stuff up there – but jokey, bar room type gimmicks and wanted to put up something more classy and railway themed.  Furthermore, the original décor script was in Afrikaans, which our overseas friends (especially SIA members) wouldn’t understand.  The new locomotive themed decor, pictures without words, is a language that any steel-wheel buff can understand!  The boys did well today, not only putting up dignified collection of art work in the bar car – but selecting and putting up pieces that are hand crafted, signed and which are unique pieces in their own right.

A set of soldering iron branded drawings of locomotives were finally put up after hanging around in the club house and at risk of being damaged.  (Pic C03 above)  A special piece made in leather takes pride of place at the end of the bar.  (Pic C04 below)  It is the last work by a recently deceased friend of the Reefsteamers and a lover of steam.  It’s appropriate that we can remember him every time we relax in the bar car or proceed through on Coach Controller or Train Management duties.

Lex Wehmeyer put the hangars and brackets on the pictures – enjoying the use of an electric screwdriver.  (Pic C05 above.)  He did the hangars of the soldering iron drawings by hand, as their frames are more brittle.  You can see the finished result in Pic C06 above.  An unexpected bonus of using these art pieces was that the black, brown and red colours blend in perfectly with the décor.

The big coaching project of the day was to refit shelving in the refrigerator cavity of the management Coach No.42.  This coach is essentially a self contained motor home on flanged wheels.  It was originally kitted out with a fully fitted kitchen, including a built in, heavy duty refrigerator in one corner.  (Pic C07 below)  The refrigeration equipment is 110 volts and is unusable.  Only one of the original stainless steel shelves survived, as well as a group of wooden drawers.  It was decided to replicate those shelves in wood and to remount the doors, to convert the refrigerator cavity into a cupboard, which, incidentally, will still benefit from the original insulation.  The original doors are very thick and heavy, being of solid wood block construction.  (Pic C08 below)  Finding hinges to fit the deeply inset recesses of the stainless steel frame is a future challenge, as the repair job will need to be strong enough to support all that wood.  (Pic C09 Below.)

The shelving work started, as many jobs do at the depot, with a good ol’ scrounge.  Willie found some nice piece of laminated board in the old fitting shed, and it was conveniently laid out on a central table (hence, still flat) and accessible too.  Lex and Willie had actually brought their own shelving boards to the depot but the material was too short for the refrigerator cavity.  (Pic C10 below)  Something that complicated the job is that the back panel of the refrigerator cavity isn’t parallel to the front.  It actually tapers inwards, following the vestibule line, as the refrigerator occupies the space normally taken by a coach door.  Rectangular shelving would work, with extra deep brackets at the back, and an inevitable gap – but that’s an ugly solution which is anathema to the Wehmeyer Bros.  Willie laid out the stainless steel shelf on the generously sized boards and marked the outlines, for cutting with a jig saw.  (Pic C11 below)  Lex did the sanding and planing in the shade of the ‘Tea Tree’ in the middle of the ‘The Green’.  (Pic C12 below)  No splinters for these boys!

The original mounting stainless steel mounting hardware is still intact, including the shelf supports and the front braces.  It just needed some gentle straightening and loose or missing fasteners to be repaired.  (Pic C13 below)  It took some extra work to this.  But it means that should we be fortunate to find more original stainless steel shelves from a matching coach – they can be retro-fitted with little trouble.  Fitting the shelves went with little problem, but the brothers soon came against the snag of the old fridge walls not being truly vertical.  Those carefully cut shelves are slightly too small for the cavity, but still mount well enough within the cavity.  The bare wooden surface needs to be varnished or sealed before being used for food, but the new shelving is already coming in useful to get the fridge drawers off the blue and white floor and safely out of the way!  (Pic C14 below)  The brothers managed to get two wooden shelves in place (Pic C15 below), and the stainless steel shelf is back in its place again.  There are two more shelves to be made and then the doors need to be re-hung. 

Occasionally, during the tapping and light hammering work, a out-of beat, counterpoised hammering could be heard echoing in the coach lines.  It was a reminder that the coach running gear team were at work, greasing axle bearings and replacing a set of brake shoes.  Andreas Mathee handled the bearing job – doing it unsupervised now that he’s done it a few times with his dad.  (Pic C16 below)  Andreas is also checking the stretcher beams and the horn guides, and is picking up techniques for the brake rigging work.  Cliffie Mathee and Tony King were both at work on coach No.137 and changing out the original spec cast iron brake shoes for modern composites.  (Pic C17 below)  It might sound odd, especially with all the fuss we hear about high performance brake pads for cars, but plain cats iron is one of the best braking materials against a steel wheel.  But they are antisocial in that they squeal, chatter and throw sparks.  That’s neither here or there in our 21^st century context as the old cast iron shoes are no longer being manufactured.  The composite shoes are less likely to draw sparks, but have a lower friction coefficient.  Cliffie is fretting about the ever decreasing supply of brake shoes – and in his authority as the Reefsteamers Safety Officer, he can pull a coach out of service.  With the distances and speeds that we run,