Bachmann Standard 5MT disassembly / DCC fitting

Whilst I like this model enormously and it is equipped with a DCC socket - it is very tricky to carry out the fitting without damaging the plethora of delicate features on the model.


This is made unnecessarily worse by the lack of any good disassembly instructions....I hope this blog post will help others as some instructions turn a tricky prospect into a relatively simple one...it will also help me recall what to do when I have to it again.



To separate the body from the chassis requires three screws to be removed


Firstly the piece of the puzzle that I wish I had known was to remove the screw connecting the con rod to the rear driving wheel. This allows the connector from the con rod to the body - presumably this was the speedo connection on the protoype?...if you don't remove this then you end up like this....

The second screw to release is the countersunk screw at the front of the loco, indicated by the arrow in the picture below...










The last screw to remove is the hardest to find / get at , as it is hidden below what presumably are the brake actuating mechanism...but again my knowledge of the prototype is so limited that I am only guessing...In the picture below then I have labelled four components -


(1) brake rod running down the centre of the loco, is just clipped in place, can either remove completely or just unclip from the component marked '3' below and bent gently to one side

(2) can't be unclipped just have to bend out of the way.

(3) a 'nodding donkey' shape of component which is easily lost - clips each side and then has a locating lug holding it in place in the chassis.

(4) the screw we are trying to get at. Can't be seen on the next photo, look at the one below that.











OK now you can separate the two halves of the loco, let's turn to the DCC decoder, I have used a LENZ silver 8 pin with plug. The only thing to note is that to fit in the nicely designed slot for it to go in, you should trim any heatshrink back tight to the edge of the little circuit board as here:-





And here is a picture of the controller fitted into the loco - as you can see the controller is stood vertically in a slot designed for it mounted in the smokebox area.

When reassembling the loco there is a plate that fits under the cab that will have come out when you separated the body from chassis. Here it is below...

The plate fits back with the semicircular bit pointing to the front of the loco and the hole in that fitting over the lug highlighted in the next photo...

Heljan Falcon DCC

This was a relatively easy one to fit, no screws to remove the body, just used four thin plastic strips to slip between the body and the chassis and it came off fairly easily.

One of the nice LENZ Direct (8 pin) decoders fits directly in and pop the top back on.

Unfortunately the couplings are going to be harder as there is much internet fuss about the fact that the skirt below the buffer beam has been glued on and will foul *any* couplers that are fitted...I think I'll wait and see what happens...

Gash layout

As a result of building a very simple test layout - I have learnt a few things to jot down....

The test layout has curves of down to 31cm radius and up to 41 cm radius.

An awful lot of stuff wont go around the 31cm curves, and even stuff that does, tends to get buffer lock, with the kadee couplers.

Even the 41cm curves (measured only very roughly - I should do a better job measuring) seem to derail a fair amount of stuff. Which only just confirms the min. radius decisions for the plan (which is 65cm for any longer curves and 55cm at worst anywhere). This is still nowhere near realistic, but should at least reduce some of the most unrealistic look.

Also note Tim (a) wherever possible DO NOT MAKE JOINS ON CURVES it is very hard to keep them smooth and sweeping if you do. (b) for tighter stuff consider set track - esp if nonscenic.


Some people do not use track pins as they rightly say it ruins the look of the track I wonder how they manage to glue the track down if you do it on curves?

Must try the tillig elite track

Must try more point motor operation

Must do more kadee operation to check with my current fixing mechanisms with shunting and delayed uncoupling.

Heljan Falcon in Lime Green

Although there are some reported problems with buffer beam changes, Ifound that fitting a bog standard No. 19 Kadee worked with the standard (deep) buffer beam.

The model took an 8 pin Lenz silver direct DCC chip.

Standard Radius Curves and gradients

I am back to track planning as I now plan to hae a bigger room - whaay!

Reading various articles, people often talk about standard radius curves in terms of a reference for tightness, e.g. in terms of what couplings can cope with - I have not been clear on what these equate to - so for my own reference here they are -

1st radius - 37.1cm
2nd radius - 43.8cm
3rd radius - 50.5cm

I have also been investigating gradients - the general consensus is that 1 in 25 (4%) is steep 1 in 50 (2%) ideal, I am planning on around 3% so I think I may get away with that.

Wiring

Having watched the YouTube videos on Mckinley - I am sure I want block detection and computer control options.

This I think means digitrax or Lenz.

If I use Lenz then I could also use LDT for cheaper and neater occupancy detectors - see the RS-8

http://www.ldt-infocenter.com/english/home_frame_e.htm LDT block detection

Which is also used here

http://staffordcentral.co.uk/wip.aspx see 17th Jun 07 entry ....and here

http://www.electricnose.co.uk/dcc/dccsystem.html see also ...

http://www.electricnose.co.uk/archive/000458.html

in terms of computer control everyone seems to be opting for Friewald http://www.freiwald.com/

I notice that one of the bigger Dcc specialists is close to Mum and Dad - so perhaps I could combine a trip

http://www.digitrains.co.uk/index.html

Bachmann Class 47

I have just received a lovely new Bachmann Class 47. Which really is a little too late for what I am modelling. This loco was actually built in 1962 - the year I am modelling - so I suppose it's ok.

The model has a 21 pin DCC socket - I found that using a converter to an 8 pin Lenz silver made it hard to fit the body back on, so I ordered one of the new 21 pin Lenz silver decoders and that seemed fine.

The NEM pockets seem to be just at the right height and I have used a type 19 Kadee coupler -

Bachmann 9F decoder and kadee fitting

Some notes on fitting a decoder to a Bachmann 9F - for my own poor memory and to help others...

First release the pony truck front bogie by releasing the obvious screw (green arrow indicates)

Then release the two screws shown by the red arrows and the body should be able to be removed.

I fitted a LENZ silver, note that a LENZ silver direct would not fit.

I always cover my decoders with 13mm heat shrink insulating tubing from Maplin. A quick blast with a hairdryer is sufficient to shrink it around the decoder.

Then I placed the decoder in the smoke box of the 9F...

While I was at it I fitted Kadees in the NEM pockets - they were perhaps very slightly high - see pictures against the height gauge below.

I used number 20s but I think 19s would be fine (I had run out of them so couldn't try)..

Fiddling with the track plan

I have fiddled with the track plan to eliminate the three way points (not available in peco code 75) and to put an extra crossover in - and to get the max radius back to 60cm - but on the main scenic parts of the track the major curves are all 80cm or better.

This version also shows all of the trestle construction which has been designed to keep the woodwork from fouling the tortoise point motors that will go under the circuit.

American Drills and Taps

Thinking about Kadee couplings you get offered taps and screws and drills you get advertised by Kadee - these come with confusing notations like 2-56 and #50 - here is a decoder to those notations - concentrating on the small sizes relevant to Kadees

American Drill Sizes

#43 ....2.2mm
#48 ....1.9mm
#50 ....1.8mm
#53 ....1.5mm
#56 ....1.2mm
#62 ....1.0mm

American Screw sizes

Tend to be of form X-YY (e.g. 0-80) where X is the diameter and YY is the threads per inch

000 ~ 0.85mm
oo ~ 1.2mm
o ~ 1.5mm
1 ~ 1.85mm
2 ~ 2.2mm

Kadees

I have been doing lots of work on kadees, I have modified some of my stock, and researched a lot.

It seems very complex, with a bewildering array of kadee types and fixings.

It isn't helped by the fact that the NEM standard that should help and is bandied around alot is both poorly adhered to and poorly explained...

There seem to be two relevant standards -

The NEM 362 http://www.miba.de/morop/nem362-d.pdf
and the NEM 363 http://www.miba.de/morop/nem363-d.pdf

though everyone seems to just talk about NEM coupler pockets.

Whilst I have found the Kadees for NEM (17 though 20) work ok in the 362 pockets, they rarely seem to work well in 363 in my very limited experience.

Sorry can only find the standards in German, think may have to get them translated.

There also seems to be a real need to gather everyone's UK conversion experience together and no-one has really done a solid job on this.

A Track Plan

Only working intermittently whilst I am here and not in Oxford.

But I have settled on a track plan. Well I say settled it has been through about 40 revisions. I am using the freeware Xtrkcad, which is actually very good once you get up the learning curve.

The room is about 5.5M by 4M at maximum, but it has the boiler room taking out a corner of it, and it is also narrower at that end.

I have now built two of the trestles and have bought the wood for most of the rest, but not done much more, apart from succumbing to an occaisional shopaholic desire to purchase lovely models - mostly locomotives.

I have been thinking and experimenting with couplings a lot and more on that anon.