Highland Railway Treble

The Chairman of my local club received a call asking if we would like some HR models, the lady calling said her father had gone into a home and they were clearing the house. If we didn't want them they would be going in the bin

He saw some pictiures and said thank you very much. Thinking he was on the way to collect some 4mm stock and buildings, was greatly suprised to find they had grown into fine 7mm models .

So for a charitable donation to the club I now some stock and a model of Fortrose Station building and the Engine shed.

There was 3 locomotives, a 4-4-0 Loch class, 4-4-0T Yankee Tank and a rebuilt 2-4-0.
The Yankee tank was the only motorised loco the others appear to have been static models.

This thread covers the restoration of these three locomotives.

The Loch was started first - and I forgot to take some initial pics

but do have them now for the other two

Yankee Tank

2-4-0

All three are suffering from paint ingress into the bearings, wheels, brakes and coupling rods.

The Loch appears to be based on an upscaled 4mm 5522 Loch kit.

I started on the Tender first, the foldup chassis is very narrow 22.5mm whereas Big Jim's 4F tender chassis is 26mm, the original builder had used some thin ply to pack out the wheels, unfortunately paint had soaked into the ply fused the chassis, axles and wheels into a solid block.

Before tackling that issue I had to dismantle the chassis, this was soldered into place rather than using the locating screws, soldering iron wasn't going to cut it, nervously - actually very very nervously the Proxon blow torch was broke out and did the job in seconds.

Now I could gain access to the wheels, and with difficulty removed the wheels, then axles.
I did my usual cleanup of the axles then with the proxon heat to a blue colour and drop into a jar of cooking oil. The wheels were chemically blackened. The chassis just had holes for the axles, for the rear axle was reamed out and standard bearings fitted, the front and middle axles had a beam compensation system fitted, but no play in the axle holes. To use this feature I cut the frames and fitted Roxey square hornblock bearings, a piece of 1mm wire being soldered in place to stop the bearing rotating.

Stripped of all paint the chassis was primed with etch primer, then painted with Vallejo Premium black.

That's us uptodate on the chassis. Brake gear still to be refitted and additional pickups.

Chassis body

Generally in good condition, with just a few handling repairs to sort, and unfortunately as the paint had been applied without an etching primer coat, tended to peel off, so I stripped it down and repainted the in etch primer.

A little filler required, and I need to create & print a new Hand Brake Screw assembly and a Water filler.

And there's more.......

Paul

 

Now the loco

Disassembly was a nightmare, I found the two retaining screws, and removed them , the rear of the chassis broke free, however the front of the frames appeard well fixed, not knowing if this had been soldered in place - as was the case with the tender chassis, I scrapped back as much paint as I could and it appeard that the chassis was soldered to a bracked behind the buffer beam

Actually that beam is part of the chassis it locates into slots cut into the buffer shanks. But due to paint and corrosion of the steel buffer head shanks the whole assembly was stuck fast. Again the Proxon came to the rescue.

That was just the start, all of the wheel retaining screws were stuck, and the hex sockets just rounded off. I tried the usual WD40 soaks but wasn't working, chatting with Rob Pullham and York Paul and trying various methods, I was left with cutting a slot in the screw head then using a centre punch or small screw driver to free off the screw. Fortunately that worked.

Chassis is now stripped, brake gear and hangers removed,

Front braket refitted

and a Roxey 40:1 short gearbox built and fitted.

The brake hanger support hole can be seen and will foul with the motor. Another job to add to the list

Buffer shanks cleaned up, and refitted to the buffer beam

Need to complete the rolling chassis, but there is enough space for the motor and a flywheel, with a decoder in the boiler. Before starting on the loco body.

I have to say I have really enjoyed this rebuild so far, worrysome in places but a pleasant challenge - hopefully it stays that way.

Paul

 

Hi Rob

The answer is yes and no or depends.

Most decoders the stay-alive is an optional extra, often as expensive as the original decoder.

AFAIK - The Stay-alive helps overcome pickup issues, whereas the flywheel smooths out the motor. The end effect for both is a more consistant smoother locomotive.

They are supposed to work fine together, as the motor driver circuit uses Back EMF to control the motor - i.e. gives a pulse to the motor and looks for feedback if the motor moves, if the feedback is too small or none existant then it sends a longer pulse untill it gets the response it's looking for, on the otherhand if the feedback pulse is too long it will cut the next pulse down to achieve the target pulse. The flywheel will make the initial pulse greater as it has more initial mass to move, once moving will smooth out the motion as the mass will help keep the motor in motion and reduce the notchy effect of the motor.

The big advantage is I can remove / replace the flywheel and test the difference

The advantage the Decoder has over a DC controller is that the feedback is far faster - distance from motor to decoder is probably less than 50mm whereas for a DC system the distance will be several meters.

Paul

 

Not sure which decoder I'm going for, based on the stall tests I did on the 4F, I'll probably get away with a 4mm decoder and add a stay-alive.
The motor being fitted is a Maxon 1833, so most 1.3A normal and 2.0A peak should suffice.
But I'm jumping ahead here, I still have the wheels to prep, and will do the 10BA mod on them.

Paul

 

The parts arrived from Slaters but not before the family caught a dose of COVID, so there has been sweet FA progress.
However I do have a question

The packet of Crankpin conversion set (Ref: 7805) contains two crankpin bushes and two long screws.

The bushing is the same size as the original bushes supplied with the wheels

Which way am I supposed to fit them

As per middle drawing insert first bush and coupling rod, then fit second bush and piston with the washer and nut on the end.
Or as per the right hand drawing with the inner bush faces towards each other.



And theres more

The bush dimentions are 2.9mm total length, with a 0.3 collar giving a 2.6mm long bush area.
My rods are 1.4mm thick giving 1.2mm of spare capacity per bush.

Now I have bought some 4mm dia brass rod, so the temptation is to turn some bushes nearer the correct size, but also thread them 10BA.

Paul

 

Had a chat earlier with Rob - old school using a phone, jeez talk of nostalgia.

And I had asked a fair question, with an answer of depends hence the phone call.

Looking back at my crude sketch



The middle option would be the preferred option for a simple outside cylinder loco, whereas if a return crank was needed then the right hand drawing is the preferred option.

Of course option 3 not shown was also discussed



Making a longer crankpin bush.

Now not having much experience on the lathe, and having bought some 4mm dia brass rod, these seem like an ideal learing job.

Dimentions

Bush diameter 2.2mm, bush length 3.0mm (Coupling rod + Piston rod = 1.4 + 1.4 = 2.8 plus 0.2 play) collar approx 0.3mm. 10BA tapping size = 1.4mm.

A length of brass rod was cut off, mounted in the chuck and faced off.
Centre drill used to establish the true center / initial piolt hole for the 1.4mm drill
The 1.4 mm hole was drilled to approx 5 to 6 mm depth.
The drive belt was then removed from the lathe head, and with the 10BA taper tap in the headstock, the lathe chuck was turned by hand to cut the initial thread. The taper tap was the exchanged for a bottoming tap and the thread fully cut.

 

Slight technical issue, part way through the last post ......

Now the bar was turned down to 2.2mm and the rods checked for clearance and length.

Now the parting tool was brought for the first time.
I did ruin 1 bush as I hadn't got the parting tool height set correctly.

But ........

Two of them made up.

Then NUTS, actually WASHERS I didn't have any 10BA washers - now on order.

Almost ready to put the wheels back on the beast.

Paul

 

Another step forward, I've ordered up 6 Laisdcc std decoders with a 8 wire harness (these will get cut off to length).
These supply 1A continuous current and 2A peak, and if unsuitable can be used on many other loco's, and at just under £11 each inc p&p, are worth a punt. Will need to get the Stay alives elsewhere as the ebay seller didn't stock them.

Feeling lucky so may spray the chassis with etch primer.

Paul

 

Insulation tape used to mask up the slide bars and primer applied

Black paint tomorrow - if the boss allows

Paul

 

Actually applied Green to the cylinders - unfortunately the paint I have is Ford Laurel Green, even the Acrylic version is only available in a rattle can.

Then masked out the cylinders

Then set loose with the airbrush and Vallejo Premium Black.

Time to let it harden and re-check for faint spots.

Now to glean up the wheels and prepare for paint.

Paul

 

Wheels cleaned and chemically blue'd / blackened.

Then masked - different coloured tape per wheel pair.

Then sprayed - outside only

10BA countersunk screws fitted (still need to be locktited into place), and fitted to the chassis

Joe le Taxi duties immenant, so laters .......

Paul

 

Thanks Andy, and with a wee bit of tweaking is smoooooth.

Tried the body in place - well you just have too .....

Nuts, on closer inspection the boiler is not round but more flat bottomed and the sides are fouling the wheels.

I reckon if I solder the parts of the boiler to the splasher sides (they are toughing already and look ok), I can then remove the remaining extra metal and all should be ok.

Time to strip the paint. Back to old faithful, neat Dettol, couple of days later, a good scrub with a tooth brush and cream cleaner, with a final wash in the ultrasonic cleaner

And the offending bits

Bit of a *** removing the paint from the cab interior, but running hot water worked wonders in melting the 70G solder that held the roof in place.

Just been thrown a curve ball, the club chairman has asked if Another Bridge could go to the Dundee show in approx 6 weeks

Damn that means i'm gonna have to fix the traverser ........ oh well another thread to be raised from the dead.

Paul