Hornby Dublo DCC

[Captainkirk]

Most of my locos are 2 rail Hornby Dublo with some later Hornby. In fact it was my intention to collect at least one of each of Hornby Dublo locos and rolling stock.

I never caught the DCC bug but I do appreciate that the sound makes a great difference to operating a layout.

 

I am now retired and do not have loads of money to spend now, but I have considered buying some Lenz loco decoders but as I understand it the basic loco decoder does not produce sound, but control only. Hornby appear to sell the TTS sound decoders for various locos, but my HD locos draw 600 – 750ma even after remagnetising -too much for the Hornby TTS. I take it I would have to purchase these as well and piggy back them to the control decoder? If so does it have to be a Hornby control decoder or can the TSS sound be fitted with any other decoder.

 

I have also seen some American model rail forums where sound decoders are available to operate off the original 2 rail DC controlled layout - this may be my preferred route – are there any UK suppliers of DC (analogue) sound decoders?

 

 

[BR60103]

I can't help with the sound modules, but there is a DCC problem with the Dublo locos where one of the motor brushes is mounted directly in the loco frame. The brush needs to be separated electrically which involves delicate machining that probably affects the collectable value.

[Crewlisle]

When I converted my 00 gauge layout 'Crewlisle' to DCC 10 years ago I wrote an article 'To DCC or not to DCC' about how I converted my DC layout & locos to DCC which was published in Model Rail.  This is the extract from the article of how I converted my Wrenn/HD Duchess to DCC:

 

The real labour of love and challenge came from my Wrenn Duchess.  Contrary to some so called ‘experts’, Hornby Dublo/Wrenn locos can be converted. I used a ZTC 4007 decoder together with a female-wired socket soldered to the appropriate wires.  Eventually I hope to replace it with a sound decoder when available.  This loco has a cast chassis, cast body and driven by a powerful, quiet motor in the firebox.  It easily starts six coach expresses on my 1 in 38 approach to the high level terminus without slipping so it was worth the effort to convert it to DCC.  To convert Wrenn or Hornby Dublo locos to DCC both brush holders, which pass through the chassis, have to have a plastic insulating sleeve fitted.  The rear wheels were removed and after the old brush holders were carefully removed, the armature could just be moved enough to allow the existing brush holders to be drilled out.  This has to be done with a hand drill and very carefully to avoid any damage to the armature.  Keep the motor brushes, end plugs and brush springs.  For the insulated brush holders I used ‘Evergreen Strip Styrene’ No. 226 which has an internal diameter equal to the diameter of the motor brushes and brush springs.  The external diameter is 4.76mm and when drilled to this diameter is a push fit through the chassis.  The insulated brush holders were cut so that one end was about 2 to 3mm from the armature and projected out of the chassis the other end by about the same.  The orange and grey wires from the decoder were each soldered to one of the original brush holder plugs and the brushes, springs and plugs were inserted into the brush holders.  The end of the plugs can be opened out so they are a tight fit to keep the springs and brushes in the holders.  The track supply from the insulated wheels was soldered to the black decoder lead and a hole drilled and tapped 8BA into the chassis to pick up the red supply, ie the supply from the non insulated set of wheels which make the chassis live.  Two things to remember when converting Wrenn or Hornby Dublo locos:

 

1. If you dismantle the two arms of the magnet, it will probably require re-magnetising.  After I had finished and was running the loco I noticed that I had to apply about 75% power to start and then throttle back to control the loco.  I tried various settings on the CVs to improve the starting characteristics without success.  I rang ZTC, told them the symptoms and they diagnosed that the magnet required re-magnetising.  The last time I had this done was about 20 years ago but was told by ZTC that they naturally lose their magnetism.  I ordered one of the new NE magnets from Tony Cooper in Accrington and the improvement in performance is excellent.

      2. To assist the brushes to bed in, carefully file the ends of the brushes to the approximate diameter of the armature.  As they bed in, control and power will   improve.

 

Peter

Edited December 4, 2018 by Crewlisle

[SRman]

I would not recommend the Hornby TTS sound decoders for the reasons stated in the OP - i.e. insufficient support for the power drawn by the HD locos.

Alternatives are dearer, but could include, in increasing order of prices, the relatively new Soundtraxx Econami decoders with UK-based sounds, Zimo decoders, or ESU Loksound decoders, all of which should have sufficient power-handling capacities.

[Tony Burgess]

Most of my locos are 2 rail Hornby Dublo with some later Hornby. In fact it was my intention to collect at least one of each of Hornby Dublo locos and rolling stock.

I never caught the DCC bug but I do appreciate that the sound makes a great difference to operating a layout.

 

I am now retired and do not have loads of money to spend now, but I have considered buying some Lenz loco decoders but as I understand it the basic loco decoder does not produce sound, but control only. Hornby appear to sell the TTS sound decoders for various locos, but my HD locos draw 600 – 750ma even after remagnetising -too much for the Hornby TTS. I take it I would have to purchase these as well and piggy back them to the control decoder? If so does it have to be a Hornby control decoder or can the TSS sound be fitted with any other decoder.

 

I have also seen some American model rail forums where sound decoders are available to operate off the original 2 rail DC controlled layout - this may be my preferred route – are there any UK suppliers of DC (analogue) sound decoders?

Hi Captain Kirk.  To answer yr last question - yes there are sound decoders which will provide excellent results on analogue DC layouts.  They are designed for both DCC and DC, and are found amongst the decoders with the very best features.  Leading brands for which sounds of UK locos are available are ESU Loksound and Zimo, and there may be others with which I am not familiar.  Many UK suppliers but do your research regarding the quality of the sound projects before shortlisting for purchase, and maybe then write to say that you intend to operate on DC.

 

What will you get, and what will you miss, on DC?  DCC controllers offer you a range of Function buttons which allow you to activate specific sounds like the whistle or horn.  Some projects feature as many as 15 or even 20 Function-called sounds, and I wonder how many are actually used in practice.  Your DC controller has no means of triggering these Function calls.

 

What you get on both DCC and DC are the basic motive power and braking sounds - varying with speed and load - plus Random sounds such as water injector, coal shovelling, etc as steam loco examples.

 

The technology exists for "superimposing" DCC Function calls over a DC supply though the special boxes for accomplishing this may only work for certain decoders.  An example would be DCMaster for the US "Blueline" locos which also addressed ESU Loksound ver3.5 decoders but not the subsequent ver4 (and presumed the imminent ver5) decoders.  DCMaster allowed activation of Horn/Whistle, Bell, an Auxiliary output, and Sound Volume on the then-customary US Function call allocations.  You could enquire of Gaugemaster as they may have a more modern unit capable of "true" simulated DCC Function call on DC.

 

Final comment.  UK loco sound projects are sold by the various suppliers in such a way that elements are copywrite protected.  That means that some things cannot be changed except by the supplier holding the original project file.  Depending on your skills and inclination you might wish to incorporate a flickering firebox light to accompany coal shovelling within Random sounds.  Request that from the outset, and you are future-proofing your purchase for future owners as well as yourself - any additional cost should be trivial as it is so simply accomplished.

 

The difficulties of converting a 2-rail Wrenn Pacific has been mentioned.  I have a feeling that at least in their closing years HD and HD/Wrenn locos were constructed such that a DCC conversion was easier.

[Tony Burgess]

Most of my locos are 2 rail Hornby Dublo with some later Hornby. In fact it was my intention to collect at least one of each of Hornby Dublo locos and rolling stock.

I never caught the DCC bug but I do appreciate that the sound makes a great difference to operating a layout.

 

I am now retired and do not have loads of money to spend now, but I have considered buying some Lenz loco decoders but as I understand it the basic loco decoder does not produce sound, but control only. Hornby appear to sell the TTS sound decoders for various locos, but my HD locos draw 600 – 750ma even after remagnetising -too much for the Hornby TTS. I take it I would have to purchase these as well and piggy back them to the control decoder? If so does it have to be a Hornby control decoder or can the TSS sound be fitted with any other decoder.

 

I have also seen some American model rail forums where sound decoders are available to operate off the original 2 rail DC controlled layout - this may be my preferred route – are there any UK suppliers of DC (analogue) sound decoders?

So I decided to check the loco & motor wiring on a 2-rail HD loco - in this case BR(S) "R1" 0-6-0 tank model 2206 dating from the early 1960s (only 55+ years since purchase, and still on our layout).

 

Electrically it should be an easy hardwire DCC conversion.  If the photo uploads correctly you can see -

     A  a tag connecting to the chassis (which is Left Rail)

     B  a green wire from the Right Rail wheel pick ups

     C  the brush spring arm which is already insulated from a motor brush

     D  the brush spring arm which will require insulation from the other motor brush

 

I don't know how common this design was amongst HD 2-rail locos, or when it was introduced.  I doubt the HD/Wrenn models had different motors installed.

[SRman]

The R1 is atypical, but is one of the easiest to convert to DCC - I have done one myself. Converting old Triang locos with the X04 motors is very similar to this.

Connect the green right-hand track wire to the red wire on the decoder (step B), the black decoder wire to the return path (chassis, step A), then the orange and grey wires to the brushes (steps C and D), making sure you insulate the spring wire from both brushes (as you have said in step D). If the loco runs the wrong way, reverse the orange and grey feeds.

Many other HD locos have the motors partially built-in to their chassis, with one brush sleeve force-fitted into the casing as the return current path. If this is the case in your other locos, you will need to drill/ream out the hole for that brush holder, and sleeve it with insulating material. I haven't done this operation myself, but I know of others who have done it successfully.

[DCB]

Probably the easiest way to convert most H/D locos to DCC is to fit rim insulated Romford Markits wheels all round to the locos with pickups on both sides.that way the pick up leads can go straight to the decoder leaving the chassis deadto the rails but live to one brush.  It was pretty much standard practice in the 1960s when converting 3 rail to 2 rail as Romfords were only available with shiny rims in insulated as the non insulated being just plain grey mazak. Drilling the non insulated brush holder hole oversize is an engineering job wheel changing is a doddle especially if you use the modern crankpins or the Triang ones I use.

The Duchess and A4 wheels are only a scale 5ft 9" which is mildly ridiculous.   My 26 mm Romforf fitted Duchess pulls 8 Hornby Dublo coaches or 16 Bachmann ones up a 1 in 36 easily. 

[Harlequin]

I'm afraid you're talking to yourselves, guys. Captainkirk made this one post on December the 2nd and has apparently never been back since.

[John K]

I'm afraid you're talking to yourselves, guys. Captainkirk made this one post on December the 2nd and has apparently never been back since.

 

Klingons?

John K

[DCB]

I'm afraid you're talking to yourselves, guys. Captainkirk made this one post on December the 2nd and has apparently never been back since.

Someone else might search this topic so its no big deal.

[Graham Radish]

I would not recommend the Hornby TTS sound decoders for the reasons stated in the OP - i.e. insufficient support for the power drawn by the HD locos.

 

 

I would not recommend Hornby TTS for anything.

[Sir TophamHatt]

I can't help with the sound modules, but there is a DCC problem with the Dublo locos where one of the motor brushes is mounted directly in the loco frame. The brush needs to be separated electrically which involves delicate machining that probably affects the collectable value.

I think I had this with a model I had.

 

I ended up swapping the whole motor out for a CD version instead.

Runs better and means I don't need to worry about brushes or messing about like that.

[Captainkirk]

Thank you to everybody for taking the time to reply to this thread, it was and still is appreciated.

David C Broad is right _ I was taken seriously ill at the time and was not even able to go online nevermind reply to the posts.

 

I can manage limited time online now and I found my login details for the forum, and found this old thread. I do not think I will be involved with my model railway now as I had to move home and it was all packed away. As someone else said hopefully your contributions were helpful to someone.

Thank you and best wishes

 

Captainkirk