Hornby M7 R2735....where to fit decoder.?

[250BOB]

Hi Guys

My pal has this DCC ready model, which he intends to use as station pilot on his model of Bournemouth West. He already knows, having run it on analogue, he is going to have a traction problem pulling a rake of 6 x 12 wheeled pullman coaches.....on the level too.

 

So.....how to increase the traction is the target here.

 

Where to put the decoder, which decoder to use, in order to not have to remove any weights from the loco....and to leave some space to add some extra weight.

 

Any help appreciated.........Bob.

[Oldddudders]

Where to put the decoder, which decoder to use, in order to not have to remove any weights from the loco....and to leave some space to add some extra weight.

The news isn't good. Even using a teeny-tiny decoder, e.g. CT Electronik DCX75S, you have to follow Hornby's instructions and remove the weight from the right-hand water tank. There is precious little room, even then. I find on the flat mine will manage 3 Hornby Maunsells, maybe plus a 4-wheel van, but forget pulling 11-car ECS from Waterloo to Clapham! Giving up the cab and bunker to a decoder might help, but you don't want weight anywhere but over the drivers. Nice models, run well, but skins and rice pudding come to mind!

 

EDIT : Oh - and keep a firm eye on the whistle. My 3 M7s are all whistle-free now!

[RFS]

The TCS DP2X-UK decoder will fit (just) as it doesn't have a wiring harness and just replaces the blanking plug. You don't need to remove one of the weights either.

[Butler Henderson]

The trick with the TCS decoder is once it is in the socket refit the chassis by first making certain that the decoder has slid into the boiler space - suspect that any subsequent removal of the body will pull the decoder out.

[34theletterbetweenB&D]

When I have finally decided what to do with my M7 chassis it will be in for some major reorganisation. Why oh why put the decoder socket up front? Airspace around the socket, and a decoder, right in a space where ballast needs to go. Stick it in the rear of the loco where there is ample space. What I would be aiming for if planning to run an M7, is replacement of all the manufacturer's ballast ahead of the second coupled axle in lead for its' greater density, and as much as possible below the footplate, thinning down the keeper plate and gluing on lead sheet, replacing the air reservoir in lead, etc.

[BromsMods]

See http://www.bromsgrovemodels.co.uk/hornbym7dccinstr.htm

[Peter Bedding]

I was most reluctant to remove any weight from the model. I used two ZTC 4007 for my first two modifcations, then changed to the TCS DP2X-UK (from John Russell!)for the third. In each case I removed the moulded ridge on the underside of the boiler to ensure sufficient space for reassembly; this last always being the part I dislike most.

 

All three decoders perform equally well, though if I should fit another, I would stick with the TCS product.

[Wicor Models]

What I did with my M7s was to remove the PCB that carries the socket and file the area flat. Cut all the wires then hard wire the decoder as though it was a non DCC ready loco and finally stick the decoder in the place that the original socket was located. I have used a Gaugemaster Small Loco Decoder (DCC21) in mine and it's worked fine in all 3 installations that I have done.

 

Dave

[10000]

Anyone thinking of trying the Zen (dccconcepts)  ZN8D Nano direct fit, don't bother its to thick.

 

Also to thick for the Adams radial

[Butler Henderson]

One of my three M7s has a TCS M1 [bBC]other small / smaller decoders are available[/bBC] hard wired in place by the simple expenditure of removing the 8-pin socket and all of Hornbys wiring with the sole exception off that from the pick-ups. One of the simplest hard wiring jobs ever with the motor wires soldered direct to the motor and one pick up wire to a tag on the chassis block, leaving just one wire to that from the pick-ups to have an isolated joint made. For clarity no weights were removed.

[10000]

One of my three M7s has a TCS M1 [bBC]other small / smaller decoders are available[/bBC] hard wired in place by the simple expenditure of removing the 8-pin socket and all of Hornbys wiring with the sole exception off that from the pick-ups. One of the simplest hard wiring jobs ever with the motor wires soldered direct to the motor and one pick up wire to a tag on the chassis block, leaving just one wire to that from the pick-ups to have an isolated joint made. For clarity no weights were removed.

 

I am aware that I can hard wire it.

But I  have plenty of older stock thats needs hard wiring so when I buy newer items that are supposedly DCC ready I should be able to easily fit most brands of decoders without having to modify the body shell/ remove weights or hard wire.

 

It seems to me that in the model railway world we put up with to much of this from manufactures.

[Oldddudders]

I am aware that I can hard wire it.

But I  have plenty of older stock thats needs hard wiring so when I buy newer items that are supposedly DCC ready I should be able to easily fit most brands of decoders without having to modify the body shell/ remove weights or hard wire.

 

It seems to me that in the model railway world we put up with to much of this from manufactures.

 

The M7 was offered DCC-fitted, using one of Hornby's own decoder products which sat comfortably in a side tank in place of the weight. Thus the DCC-ready version was simply that arrangement with the decoder missing and the weight in place. The M7s have been on the market for quite some years. Hornby is moving on - the latest Bulleid Pacifics have the decoder in the tender, rather than the loco as before. 

[10000]

The M7 was offered DCC-fitted, using one of Hornby's own decoder products which sat comfortably in a side tank in place of the weight. Thus the DCC-ready version was simply that arrangement with the decoder missing and the weight in place. The M7s have been on the market for quite some years. Hornby is moving on - the latest Bulleid Pacifics have the decoder in the tender, rather than the loco as before. 

 

Yes I'm well aware that Hornby is moving on but its not just Hornby at fault. All of them including decoder manufactures need to get their acts together.

 

I have an Intermountain SD40 waiting for a sound decoder. It takes a 21 pin. I was on the verge of buying a TCS wowsound 21 pin for it, but something told me to open it up first. What I found was that the space for the decoder is to small for a TCS. The only one that will fit is the American ESU loksound, the one they factory fit.

 

Think of it like this:-

I have 2 digital cameras, one an SLR and the other a pocket size.

They use different types of memory card (think of 8 pin socket and 21 pin connector.) As long as I buy the correct type of memory card for each camera it doesn't matter which brand it is, it physically fits in.

Thats what we should have in the model railway world.

[34theletterbetweenB&D]

...The M7s have been on the market for quite some years. Hornby is moving on - the latest Bulleid Pacifics have the decoder in the tender, rather than the loco as before. 

 It's the H class 0-4-4T where we will be able to assess if there has been progress at Hornby. It is pretty obvious that the layout to use is lighter stuff to the rear over the bogie (DCC socket and decoder void), the motor to the rear of the second coupled axle, and the gear train to the second coupled axle, reserving as much as possible of the space above the coupled wheelbase for solid metal ballast to maximise the weight there. (To ice the cake, make the fitted ballast easily removeable, so that those who choose can substitute lead, with its usefully greater density for yet more weight.)

 

In 'positive news' Hornby's D16/3 4-4-0 has the motor forward of the coupled wheelbase, allowing as much ballast weight as possible over the coupled wheels, resulting in good traction with no need for traction tyres. Since the 4-4-0 is effectively the mirror image of the 0-4-4 and presents the very same problem of getting the weight in the right place over the coupled wheelbase, then hopefully that proven layout will guide the H mechanism layout.

[JohnR]

Anyone thinking of trying the Zen (dccconcepts)  ZN8D Nano direct fit, don't bother its to thick.

 

Also to thick for the Adams radial

 

I'm surprised to hear this - the description says it is smaller than the blanking plug! I'm currently looking at fitting my M7, and was looking at this decoder, given the well known issues with space, partly because I want to use a Stay Alive as well. 

[Butler Henderson]

I'm surprised to hear this - the description says it is smaller than the blanking plug! I'm currently looking at fitting my M7, and was looking at this decoder, given the well known issues with space, partly because I want to use a Stay Alive as well. 

Its the proportions of it that is the problem - it is smaller in volume but crucially a mm higher than the TCS DP2X-UK I bought one and found it would not fit a number of models that the TCS decoder does fit in. DCC Concepts are very good at the hype but the reality is often a different story with their products IME.

[Art Dent]

Hi folks, just an observation.

 

The OP mentioned traction (or lack of it) as a potential problem.

 

To address this (as so far all posts and discussions have centred around how to fit a decoder) have you considered the DCC Concepts Power Base (link > https://www.dccconcepts.com/product/powerbase-starter-kit-ooho-scale/ )

 

Not used it myself but from what I've seen has a significant effect on traction.

 

Art

 

(no affiliation to DCC Concepts - just a used of some of their products)

[andyman7]

Hi folks, just an observation.

 

The OP mentioned traction (or lack of it) as a potential problem.

 

To address this (as so far all posts and discussions have centred around how to fit a decoder) have you considered the DCC Concepts Power Base (link > https://www.dccconcepts.com/product/powerbase-starter-kit-ooho-scale/ )

 

Not used it myself but from what I've seen has a significant effect on traction.

 

Art

 

(no affiliation to DCC Concepts - just a used of some of their products)

I just took a look out of curiosity but have to say that all the info assumes that the viewer knows waht the powerbase actually is. I am none the wiser except that it seems to involve magnets.....

[Art Dent]

I just took a look out of curiosity but have to say that all the info assumes that the viewer knows waht the powerbase actually is. I am none the wiser except that it seems to involve magnets.....

 

Yes, small neodymium magnets attached to the underside of the loco and metal plates (steel?) fitted under the trackbed.

 

'Pulls' the loco down (in much the same way as extra ballast) meaning less tendency for wheel-slip and therefore greater traction.

 

At least that's my understanding.

 

Harks back to Triang-Hornby's 'Magnadhesion' of the late 1960's.  Worked because the Triang-Hornby Series 4 and System 6 track was steel and not nickel-silver and was thus magnetic.

 

Art