Hornby LMS Jinty 7414: DCC or Analogue?

[carlwebus]

Hi All

 

Some  time ago I bought off eBay a second hand red Hornby LMS Jinty 0-6-0T No.7414 - sold as taken from the Hornby Night Mail set and with the statement  that it was DCC   fitted with a chip that would, however,  function on non-DCC track.

 

I double  checked and it seemed that the latest DCC as  fitted to this model,  would run DCC or analogue.

 

The loco will run on my non-DCC rails - but only slowly and with much power on the controller.

 

I attach a picture of the chip that is hard wired into the loco.

 

1) Can someone confirm that the chip is DCC (or  that it is not)?

2) I propose to cut the chip off and reconnect the  wiring without it.  I think it will be  grey to  black and orange to  red.  Is that correct?

3) Can anybody suggest a kit, resin or 3D printed body that will  fit on this  chassis (I already have a Midland 2441, GW 97XX, Southern E2 and LNER N7)?

 

[The Johnster]

1) Yes

 

2) Yes, TTBOMK.  You could also simply remove the chip, the bit that looks like a fat centipede with a blue spot on it, which would leave your loco in 'DCC ready' condition without the need to disconnect wires and solder them back together.  I'm not au fait with DCC matters, but it may also be possible to get the chip re-programmed to allow better DC running without even removing the chip.

 

3) '... perchance to dream.  Ah, but what dreams may come in that sleep of death must give us pause...'! 

 

The Hornby Jinty chassis, even the current one, is based on the original Rovex Triang Jinty chassis and retains it's axle spacing.  This was incorrect for a Jinty, and apparently used by Rovex to allow standard parts from the Black Princess to be used.  Sadly, it is also incorrect for any of the other models it was subsequently put under.  I do not offhand know of any British standard gauge locomotive that it is correct for.

 

I know that is not what you want to hear, and apologise for any distress resulting, but it is, sadly, the case.   If we proceed on the assumption that you are happy to live with this anomlay, and that any body you place on it other than a Triang, Triang Hornby, or Hornby body will have splashers that do not align with the wheels properly, then I would say that it is further unsuitable for a 97xx (or the Triang Hornby/Hornby 8750 or 2721), which has fishbelly not fluted parallel coupling rods.  I used it for some time as supplied under a 2721 pannier, for which the coupling rods were in fact correct in that they were fluted parallel, for the particular prototype I used this model to represent.  I eventually replaced it with a Bachmann pannier chassis with incorrect fishbelly rods that ran (much!) better, and found that the misalalignment of wheels and splashers was not apparent from anything except a dead broadside-on viewing angle, but eventually could not live with the oversized bunker on this model and have withdrawn it from service, putting the chassis back under it's original Bachmann body.  Of your other alternative locos, the best results will be obtained from those with the longest side tanks which will hide the inaccuracy better; the N7 is probably the least compromising.

 

I may be doing you no favours by pointing out the anomalies.  Once you are aware of them and decide you can live with them, they will eat away at your psyche until you can't live with them... 

 

Many of the Wills Bodyline whitemetal kits, now Southeastern Models, were designed to fit on this very chassis nonetheless, and the Bay is awash, or at least adrip, with such models.  At least more recent versions have some attempt at brake and rodding detail.  You will probably find that other kit bodies or resin & 3D printed bodyshells will not be suitable for use with it as the wheels will foul on the splashers.

 

It is annoying when an RTR manufacturer gets things like this deliberately wrong when it would have cost little or nothing to get it right in the first place.  Rovex Triang were not in the business of producing correctly dimensioned chassis, and neither were Hornby Dublo in those days, but there has been nearly 70 years to correct the error with a retooling, and yet the chassis still languishes in the Railroad range and still irritates people like me.  Bachmann's Jinty and 1F are correct in this (and most other) respects.  Hornby even produce a current chassis that might be suitable I believe, that for the J50.  The Victorian 6-coupled designs that were the basis of the late 19th and 20th century 0-6-0s that Rovex and their successors have produced fell largely into two effectively standard camps, one of which emanated from Derby but was used elsewhere, including Swindon, and was of course correct for a Jinty

 

'To be or not to be; whether it be nobler in the mind to suffer the slings and arrows of outrageous fortune, or to take up arms against a sea of troubles, to end, to die, to sleep'... which is where we came in.  Stratford Bill could have been a modeller. with that sort of attitude!

 

Nowt wrong with a bit of culture on a Friday evening...

[frobisher]

1 hour ago, The Johnster said:

2) Yes, TTBOMK.  You could also simply remove the chip, the bit that looks like a fat centipede with a blue spot on it, which would leave your loco in 'DCC ready' condition without the need to disconnect wires and solder them back together.

 

Er, no.  You'll have a completely dead loco at best because that controls the inputs and outputs of the wires. Best bet for rewiring is to tackle the wires for all this at the motor end - there what is pickup and what is motor feed becomes abundantly clear given the way these chassis are set up.

 

[carlwebus]

Thank you Johnster (or should I say Hamlet) and frobisher.

 

If only this  chassis  was like some others I have bought (J83 etc - but probably same) on which you could just unplug the chip  and plug in a blanking plate!

 

I'll look up the Wills bodyline/ Southeastern models options - 'cos it ain't going to cause me a loss of sleep - I just like making the things!

 

To be fair to Johnnster he did say TTBOMK - which I think is internet slang for  "Initialism  to the best of my knowledge", indicating uncertainty in spite of having some knowledge on the subject.

 

Returning to the "what  wires to I connect together?" question ,  the wires shown in the picture I submitted connect like this:

* white, purple, green and  yellow :  don't   connect to anything : they are just cut off under the grey tape

* grey  wire comes  from the bottom of the motor where it looks like its connected to the  chassis (and presumabley  from there to the lower motor feed)?

* red wire is connected to the wheel pickups on the left  side of the chassis

* orange  wire is connected to the top of the motor (presumably to  the top motor feed

*black wire, strangely, is connected to the wheel pickups  on the right of the chassis - but not to anything  else as it just ends in space!

 

From that I am thinking that, perhaps, my original  thought of grey to black and  red to orange was correct?

 

[The Johnster]

Rosencrantz and Gildenstern are dead.

 

I think, but am not sure, so check before you do it, that wires of the same colour as those running to the chip from the pickup strips on the keeper plate can be connected to said pickup strip wires to make a direct track-to-motor feed as in 'traditional' DC.  In fact I have done this job on a Bachmann 45xx by soldering the pickup feed wires direct to the motor terminals where there was enough slack to allow this, but wouldn't do so again because there is very little slack left should I need to take the keeper plate off...