OO Gauge class 71 Electric Locomotive

[No Decorum]

If that is the case with the head code lights I will probably leave them as they are as I can live with both being on at the same time

You don’t have to live with both being on, or at least visible. You could stick some black tape over one of the inserts. The headcode boxes seem to be fairly light proof.

[SRman]

Mine is a fairly low speed layout, with the intention being to allow viewers to see the trains glide and snake past. When the upper level is eventually operational, the trains have a length of viaduct to wend their way along too.

Even so, with the discussions on top speed at the back of my mind, I decided to video trains running at what I consider "reasonable" speeds for my layout. 

Using my NCE Power Pro system with a 15 V power supply, the two DJM class 71s are seen here with E5004 with Lenz Silver+ decoder on a Pullman train with lights on speed step 91 (out of 126), while E5003 (edited to correct a typo), with ESU LokSound v4 decoder is on a milk train at speed step 43.

While they could both go a little faster than this, it wouldn't look particularly comfortable in my layout's setting. I'll let others be the judges of what would suit their wants or needs.

Edited June 6, 2017 by SRman

[7013]

I took my 71 to my club tonight which has a very large test track, ran it for a while light engine, top speed is only about a scale 60 mph which is ok but I would like perhaps another 10-15 mph scale top end. One thing I did notice though was that with six coaches (Hornby Maunsels) on it was still able to maintain the same speed, no discernible drop off with the load on which is pleasing. Not entirely sure how I could improve the top speed (already set at max on CV5), however that said I can live with its present performance

[RFS]

I took my 71 to my club tonight which has a very large test track, ran it for a while light engine, top speed is only about a scale 60 mph which is ok but I would like perhaps another 10-15 mph scale top end. One thing I did notice though was that with six coaches (Hornby Maunsels) on it was still able to maintain the same speed, no discernible drop off with the load on which is pleasing. Not entirely sure how I could improve the top speed (already set at max on CV5), however that said I can live with its present performance

 

With a Lenz Silver you can try setting bit 6 in CV50 to increase top speed (CV50=32), described as "back EMF control for high efficiency motors".  Also top speed is reached at about speed step 100, and you can actually reduce CV5 to around 190 and it will still do around 60mph.  As a result you get a better speed curve. 

[7013]

CV 50 bit 6 ( EMF) control is either active or inactive. I have not looked at it yet, presumably it should be set to the opposite of what it reads? Or am I being too simplistic?

[RFS]

CV 50 bit 6 ( EMF) control is either active or inactive. I have not looked at it yet, presumably it should be set to the opposite of what it reads? Or am I being too simplistic?

 

Bit 6 is the EMF control for high-efficiency motors, whereas bit 7 turns EMF on or off.  This is the description of bit 6:

 

"The decoder also has what we refer to as a EMF switch which makes it possible to further adjust the decoder to different motor types. Depending on the motor type used, it is possible that a digitally controlled locomotive cannot reach an adequate maximum speed compared to a locomotive in conventional operation. If this is the case, activate your EMF switch by setting Bit 6 in CV 50. The locomotive will then reach a higher maximum speed while the minimum speed is also slightly increased."

 

​So you can try turning it on, possibly with motor type 1 - so set CV50=33. I found that the loco started at walking pace on speed step 1 of 128, but this improved a little with motor type 1. 

 

[John M Upton]

This is all waaaayyy too complicated.  Whatever happened to just plonking things on the track and playing with them in the days before all this overly complicated technical malarkey?

[Titan]

There could be an easy solution to increase the top speed, which might also have other benefits too. I discovered this by accident on a different loco and see no reason why it should not work here, although with the caveat that it was on a DC layout.

 

Most systems do not put out a smooth voltage to the motor, be it PWM or full wave rectified AC. They aim to have a maximum RMS or average voltage of 12V, which means the peak voltage is much higher. If you put a non-electrolytic capacitor of reasonable size in parallel with the motor, it will smooth the power supply and significantly increase the average voltage without increasing the maximum voltage the motor is subject to.

 

Increase in average voltage = increase in top speed. The effect on full wave rectified DC was quite substantial. I used this as a temporary fix for a tired Hornby 125 to get the speed back to somewhere near scale until a replacement motor was sourced and fitted.

 

It will also provide a voltage across the motor in lieu of back emf, which may be of use with decoders that use feedback.

[Oldddudders]

This is all waaaayyy too complicated.  Whatever happened to just plonking things on the track and playing with them in the days before all this overly complicated technical malarkey?

DCC does need and offer all sorts of variables, but that needn't bother those who don't use it!

 

DC was an entirely adequate system for modellers for decades, and remains so. The arrival of DCC has not invalidated it, merely added an alternative that some of us choose to embrace.

 

Just ignore the techie stuff.

[JSpencer]

This is all waaaayyy too complicated.  Whatever happened to just plonking things on the track and playing with them in the days before all this overly complicated technical malarkey?

 

I personally find the DJM 71 is a model aimed at serious and capable modelers. People prepared to take things apart to fit head codes, sound etc. or even just to fit the couplings and valances. The model is well honed for well laid finescale track with second to none slow running characteristics.

Hornby's is more apt for just placing on the track and ready for use, having couplings, 3rd rail shoes in place. Copes far better with variable laid or aging code 100 trackwork and high speeds/heavy loads.

 

Edit: Please note that the first phrase is not intended as an insult and I do apologize for the interpretation.

Edited June 7, 2017 by JSpencer

[RFS]

I personally find the DJM 71 is a model aimed at serious and capable modelers. People prepared to take things apart to fit head codes, sound etc. or even just to fit the couplings and valances. The model is well honed for well laid finescale track with second to none slow running characteristics.

Hornby's is more apt for just placing on the track and ready for use, having couplings, 3rd rail shoes in place. Copes far better with variable laid or aging code 100 trackwork and high speeds/heavy loads.

 

Both models have NEM coupling pockets and separately-supplied valances, if you choose to fit to one end in lieu of a coupling. They have different methods of fitting head codes but you can do so on the Hornby without taking it apart.  Both are more difficult to fit head codes to than the Heljan 33 where the plastic front window simply unclips. All models these days have excellent slow-running characteristics (so long as you don't fit a cheap decoder!) and the DJ 71 is no different in this respect to the Hornby.  My newly-acquired unrebuilt Clan Line, with flywheel-driven motor, also has superb slow-running characteristics. 

 

I needed my DJ 71 to take its turn on my Golden Arrow representation, but at 10 bogies (7 lighted Pullmans) this was way beyond its capabilities.  Regretfully I had to make the decision to return it to Kernow and replace with the Hornby version E5022. This version has no problem with speed and haulage, and its motor is silent unlike the noisy gears of the DJ 71.  DCC fitting, with a Lenz Silver Direct, was no different to fitting a 21-pin to the DJ 71. 

 

I appreciate there are pros and cons for both versions and everyone will have their personal choice. My need was for haulage and, although the DJ 71 is a nice model in many respects, it didn't deliver that.

 

EDIT: remove reference to DJ 71 having a flywheel. Only the Hornby one does.

Edited June 7, 2017 by RFS

[woodenhead]

I personally find the DJM 71 is a model aimed at serious and capable modelers.

That could be construed as insulting 

[Ian Hargrave]

That could be construed as insulting

 

I don't think he quite meant it that way but yes that's how it comes across....and perhaps misses the point. The essence of the dilemma is succinctly expressed by RFS in his post and regrettably however much we like the DJM 71 you cannot argue with that.

 

Incidentally,fiddling around with myriad bits that are beautifully packaged along with the rest of the model is beyond my eyes and fingers.Thus am I banished from the ranks of capable and serious modellers forever.Oh the shame and utter humiliation of it.

 

As some of you are aware,I have also posted on the Hattons 71 thread very much on the same lines as RFS has posted here.

That was three days ago.As they say.....the rest is silence.I leave you to take what you will from that.

 

Putting it bluntly....calling spades shovels if you like.....I expect not only slow speed control but reasonable ( oh that word again ) prototypical performance under load.I hope no one has any objection to that.

[JSpencer]

That could be construed as insulting 

 

Not intended as such and I do apologize for the interpretation. What I mean is we all have different skill levels, available time and expectations. I find this model better suited to a finescale environment with excellent trackwork , handled by people who enjoy tinkering, adding personal touches etc.

 

I would not use it on a Hornby based track plan layout with set track (in between would depend on how good your track laying is, DJM uses fine RP25 wheels and has 1 to 2mm up/down play on the bogies, which is tight, so no kinks or sharp changes).

I have a Hornby NRM version (because I like the NRM) which does not have fine RP25 wheels and a lot more bogie movement, I found I could throw any track work at it (did not try finescale however). Couplings are fitted too, which I know (and respectfully understand) a few people have had difficulty adding themselves.

DJM gives a choice of head codes without which it is just a bright light on the cab.  Hornby defaults to 2 white (or red) patches (which will just about pass under rule number 1) and then uses stickers.

 

Overall there are two products out there from which the buyer can choose between to best suit their needs.

[7013]

Interesting comments, yes you can pop your loco on the track turn the knob and off it goes. Nobody is forced to use DCC, and even with DCC you can tweak as much or little as you wish. I would not normally change some of the more complex settings on DCC, however the advice being given regarding the CVs is pertinent to this loco, it can be a bit daunting even to a DCC user like myself. I am not sure the model is aimed at only the serious and capable modeller as Mr Upton points out you can just pop it on the track and away you go. Putting the detailing bits on I note that I have only four of the eight third rail pickups in the bag so I will be contacting Dave to see if he carries spares. But I must say overall this model gets full marks from me, a superb loco which would look great with the night train coaches behind it.

Edited June 7, 2017 by 7013

[Southernman46]

This is all waaaayyy too complicated.  Whatever happened to just plonking things on the track and playing with them in the days before all this overly complicated technical malarkey?

Yup that's me - I still use a H&M Powermaster complete with all the hummimg, slight tingling from the case corners and delicious smell of brutalised AC to DC rectification ..............................

[JSpencer]

Admittedly my examples used to make my point are taking things to the extreme. The reality is lot more grey.

 

Basically one of the two models will fit each persons requirements better than the other, which will cause a sort Marmite effect on here.

 

In the end there is no right design, just one characteristic being traded against another.

[Dogmatix]

[deleted by poster]

Edited June 7, 2017 by Dogmatix

[JSpencer]

Both models have NEM coupling pockets and separately-supplied valances, if you choose to fit to one end in lieu of a coupling. They have different methods of fitting head codes but you can do so on the Hornby without taking it apart.  Both are more difficult to fit head codes to than the Heljan 33 where the plastic front window simply unclips. All models these days have excellent slow-running characteristics (so long as you don't fit a cheap decoder!) and the DJ 71 is no different in this respect to the Hornby - after all both have flywheel-driven motors.  My newly-acquired unrebuilt Clan Line, with flywheel-driven motor, also has superb slow-running characteristics. 

 

I needed my DJ 71 to take its turn on my Golden Arrow representation, but at 10 bogies (7 lighted Pullmans) this was way beyond its capabilities.  Regretfully I had to make the decision to return it to Kernow and replace with the Hornby version E5022. This version has no problem with speed and haulage, and its motor is silent unlike the noisy gears of the DJ 71.  DCC fitting, with a Lenz Silver Direct, was no different to fitting a 21-pin to the DJ 71. 

 

I appreciate there are pros and cons for both versions and everyone will have their personal choice. My need was for haulage and, although the DJ 71 is a nice model in many respects, it didn't deliver that.

FWiW There are no flywheels on DJMs 71. I think gear ratio is much higher and finer on a DJM because under classic DC I find it can creep far slower. Under DCC, feedback to the chip probably makes that point moot. Finer gears probably means more noise too.

[RFS]

FWiW There are no flywheels on DJMs 71. I think gear ratio is much higher and finer on a DJM because under classic DC I find it can creep far slower. Under DCC, feedback to the chip probably makes that point moot. Finer gears probably means more noise too.

 

Thanks - my misunderstanding! The Hornby one does as do the Heljan 33s I believe.

[JSpencer]

Thanks - my misunderstanding! The Hornby one does as do the Heljan 33s I believe.

Yep, All modern Hornby, Bachmann, Heljan diesels or electrics have flywheels. I,m not sure about the Dapol 22 or 73 which is, in some ways, the ancestor to the DJM 71.

[rubber duck]

it's a shame the shape of the cab door handrails weren't corrected before production, they should follow the curve of the body. see the other 71. 

[mikesndbs]

Quick question, is anyone else having an issue with the front bogie wheel (small vent end) derailing when the loco transitions from curve to straight when going a fair speed?

 

Mine keeps doing it, also only when under load, like the wheels are being pulled off??

[davesol]

I finally had chance to run my E5004 on my club's layout on straight DC. 

Oiled as recommended and it ran sweetly and silently straight out of the box.

Was a little apprehensive having read some other's experiences, but mine is perfect.

A most satisfied customer, now to fit the accessories and wait / save for a GA one!

[Roy Langridge]

Quick question, is anyone else having an issue with the front bogie wheel (small vent end) derailing when the loco transitions from curve to straight when going a fair speed?

 

Mine keeps doing it, also only when under load, like the wheels are being pulled off??

 

What radius curve do you have? When I ran mine in on a 2nd radius circle test track the bogies at one end seemed to be at their limit of travel.

 

Roy