A tale of three chassis - floppy no more

[The Johnster]

the problem is in the rear springs being too long even Hornby recommend shortening the springs by cutting off some of the coils

 

My solution to this was to ballast the bunker as heavily as possible despite having only half a load of coal in it.   Hornby also suggest lengthening the springs if they are too weak, but I doubt that happens very often!

[Neil]

Interesting comments re. springs and weight, my loco has no weight added and the springs are the stock items.

[The Johnster]

Easy to ballast the bunker to bear down more heavily on the rear axle, as I say I've managed a lump of blu tac in there under the coal which only half fills it.  Any extra ballast added to any locomotive is a good thing IMHO, particularly above the driving wheels.  

[Neil]

It's been almost a couple of years since my last post in this thread. Time for creeping dissatisfaction with the running qualities of the J52 to set in. It and another 0-6-0 tank engine, a J50, are both chipped so that they can visit friends layouts. While the J50 is silky smooth across the speed range the J52 was not. It could be set to circulate round with a train at a moderate pace and it wasn't too bad, but shunting just wasn't satisfactory; no good for a shunting engine. I'm still suspicious of the dreadful floppy axle. To cut a long story short whilst reading another thread I discovered that the latest China made version of the Jinty chassis has finer wheels, no traction tyres, pick up of all six wheels and best of all no floppy axle. So I went off hunting on e-bay and bought me one, a second hand Railroad Jinty in S&DJR livery. It might as well be new for all the use it seems to have had.

 

On test the difference was immediately noticeable, very nearly as good as that of the J50. I hoped that a straight swap would be in order as the dimensions of both mechanisms looked identical, however ...

 

 

.... the new chassis seemed to be a tight fit, it appeared to be catching on the boiler backhead part of the cab moulding. I fancied painting the cab interior anyway, so eventually I worked out how it came apart. Starting with the smokebox the handrails need to come out. This allows the saddle tank to come off by unclipping it where it fixes to the smokebox allowing it to come away from where it's pegged into the cab front. Getting the cab mouldings out is a bit of a nightmare as the protrusions on the footplate require the valances and steps to be flexed outwards to an alarming degree. For reassembly I decided to separate cab front, rear and floor into separate sections.

 

 

On my chassis the solid wire connection at the rear of the motor bulged outwards. I wondered if this was the cause of the problem so before attacking the backhead I bent it to lie flat against the back of the motor, slipped the cab front in loose and tested for fit. No problem so I glued the cab front in, put the cab rear in, tested, no problem, glued in. To get the cab floor in I cut it in two lengthways down the middle so I didn't have to force the steps and valences outwards, tested, b*gg*r, same problem. Eventually I worked out that I needed to deepen the cut out in the cab floor back by a couple of mm to accommodate the tag on the back of the motor which must be a touch larger on the new chassis.

 

 

Now the annoying part is that if I'd worked this out at the start I could have enlarged the cut out in the cab floor with it in position and it would have been the work of five minutes to swap chassis. However I'd still (probably) have to get the cab out to paint the inside successfully so ultimately I probably haven't wasted any time.