5258 Retrofit

[PJM699]

Well; I put it in my introduction so now I have to make it happen now if only to save face.

I have a 5258 Locomotive in which the sound card has died so is less beloved of our boys than once it was. Then I stumbled across a dead 99 805 steam locomotive at a boot fair – seemed to have been converted to friction drive at some point




So I now have a donor and a shell – people do it with cars all the time, what could possibly go wrong?


Youtube as ever is a bit of a gold mine

https://www.youtube.com/watch?v=l4rfrLQxakg
John Mellor modification;

Shows the interior so makes me think the swap could be made.

http://www.walts-playmobil-collection.me.uk/hints_&_tips.htm
and walt (many thanks) has other images available of the giblets for study


Well that's the bottom part off (the drive unit basically) – just have to take the top apart now {if I faint now, the coroner’s report is going to make very interesting reading!}.

It is at this point you realise just how well these things are made and how tight the tolerances are, there are 12 sprung catches/tabs which require basically simultaneous release to get the top off -


A quick check that the parts are all still talking when removed from their housings and pcbs etc are out of their cosy slots.

I think a couple of dumb axles are in order for the body now – possibly with a pp3 in the battery space and some LEDs in the correct positions for the lights – I'll have to talk to my technical guru about getting the colours right for direction – what seems impossible to me he will almost certainly have a very easy solution for.

After battling to measure the wheelbase off the old drive unit – I had a thought – the con rods will be the same as the axle base – I make this 72mm?

QUESTION Anyone have a more accurate idea on this? And second question which I am hoping someone will be able to tell me;
QUESTION – how are the old style wheels fitted to the axle
– is it a knurl the axle and overmold job or is there something more substantial inside the wheels? I think I can put them on the lathe and drill out the centres of the old wheels – turn-off the outers off the new wheels and shrink (superglue) the outers of the old wheels on to the new axle – the gears are completely different sadly.

The machining is all entirely possible but somewhat fraught with disaster from any minor errors!

My back-up option is to find or turn a tube the same diameter as the stub connections on the old wheels and drill through the new wheels and glue a stub into the wheel for the con rods to mount to and ignore the spoked look completely. I'll see how my stocks of bravery are doing later on

[PMatt]

I'm a bit envious of your level of craftsmanship, and stoked to see how your project will turn out!

[Junker Jörg]

Just to make sure I got right what you're up to: It's to fit old stlye wheels on the "new" diesels axles?

I've never taken axle and wheel apart, but I think I remember a chap telling me: The wheels're just jammed on to this axle, fitting tightly but no other conections. So using sheer brute force ought to bring them off - or make them break  .

And yes, I'd agree, the con rod's holes should match the distance the axles are positioned in inside the motor box.

jj:

[playmofire]

Just to make sure I got right what you're up to: It's to fit old stlye wheels on the "new" diesels axles?

I've never taken axle and wheel apart, but I think I remember a chap telling me: The wheels're just jammed on to this axle, fitting tightly but no other conections. So using sheer brute force ought to bring them off - or make them break  .

And yes, I'd agree, the con rod's holes should match the distance the axles are positioned in inside the motor box.

jj:

Yes, I'm sure that's right, just a very tight fit.

[PJM699]

Thanks for the confirmation – I think I might still machine the wheels off the old axles although I think I might go for perforation on the drill press, remove the axle by hand and then machine out the hub as trying to drill true on something you can’t get a good grip on in the chuck is bound to be disastrous. The point of this bit is to get the old steam engine spoked counterweight wheels onto the modern disc wheel axles as the drive gear is different on the two so you can’t easily have the old wheels on the new drive system.

Well, having got off to a storming start, I have entered the looking and thinking phase (I did do a little of this before starting) but I am about to pass the point of no return so I shall do a quick bit of mulling over before I chop lumps out of an otherwise nice piece of kit.

The (nice new) tweezers mark the position of the second axle post chopping. This means that ca 50mm needs to be chopped out of the chassis (now that the weight / mass has been levered out). This leaves pretty short stubs between the axles so the current plan is to chop out the various fins in the middle of the chassis frame and replace with a 25mm square bit of steel that I can tap and use both as a mass and a joiner.

The turret bits need to come off otherwise all will go to pot and then I think perhaps some epoxy resin (with a straw through the middle for the passage of wires) with some stainless steel beads to keep it all nice and heavy with less temptation to float off the rails whilst strengthening the now weakened area between the axles. I will also have a bit of scrap material to ensure that the epoxy does not ‘melt’ whatever plastic the power block is made from (I am glad that thought just popped in,) it would be very upsetting to pour in the epoxy and then watch everything dissolve into a sad little lump – maybe some other casting material might be better – will have to have a think.


Having a peer – it looks like the ends will fit into the steam frame but it’s a bit tricky but then again what isn’t. If the worst comes to it we might have to do some more cunning threading of inserts to ensure that everything goes together.
Now I turn my thoughts to power (not actually to take over the world) for the effort. Space inside the boiler is now looking pretty full due to the two circuit boards. I can put these back to back to reduce space (putting some threaded blocks between them) and then fill the rest of the space with rechargeable batteries (maybe a rack of PP3s – I will have to check what gives the best power density and also fits in the space). Power charging socket hidden somewhere underneath. Potentially a 12v if I can fit it in and then a DC-DC power control board to give 9v to the PCBs. The other but less attractive option is to have a power truck behind with small wires running to the engine over the coupling – although I suppose that a vacuum hose if seen on most locomotives.

(Nicked from Flikr loose_grip_99 Great Central Railway Loughborough Leicestershire 20th February 2016) Which would mean that I could put a serious size 12v LA battery in the truck (container mounted atop?) and the loco could run for some time! I recon I could fit about 10Ah of 12v LA in there – could set the thing going and go on holiday and find it still running when I got back (as long as we moved house to somewhere it would not get pinched that is of course)