DCC Conversion of a DMU

Hi All ,

The last item I have had on my workbench is a Fleischmann BR614 DMU Set #4438 This one was fitted with a Lenz decoder but the installer had taken a few short cuts - the soldering was not to good either. The loco would not run very well at all.

With the lid of (roof can be removed quite easily - I usually start at the rear of the car and work forward unclipping the roof)



As you can see the wiring hangs down into the cab area and is visible through the windows.

First thing is to remove the wiring , motor bogie , lamps contact brackets , lamps , main circuit board.

Previously I had made up some mini lamp replacements with SMDs soldered to resistors.
4 of each Warm White and Red for 2 sets of DMUs

Next I had a look at the Motor bogie to Clean the contacts and pickups.



This is where I had discovered that the pickups on the motor bogie had been removed

No wonder it was a poor runner!
I had replacements - there is one that contacts the axles and another that contacts the back of the wheels (on the left hand side)






Lately I have been soldering the pickups to the PCB and soldering the Brush holders to the PCB as well. I had a couple of locos that would work fine - then the next day would not run - soldering the brush holders to the PCB fixed poor contact.

 

The powered unit now has pick up on all 8 wheels (although 2 have traction tyres)

Next thing is the PCB that is inside the roof of the DMU



a few cuts with a Dremel to isolate the various sections . Holding the Dremel lightly against the PCB is all that is required . Too much pressure will cut straight through. Safety first- wear some eye protection! These blades spin at high RPM and I have had a few of the thin ones break up during use.





and some LEDs and resistors for internal lighting. I usually clean the track first and pre-tin the track before solding the LED in place. This makes sure that the LED does not absorb unnecessary heat. leaving the tail in place also helps in drawing the heat away from the components.

 

Painting the backs of the LEDs with white paint helps put the light in the correct place.



I added a diffuser (made from a plastic milk container) I also add a little white paint to this around the areas that the LEDs are.



You can spot the wires from the Stay Alive unit (This is painted white and held secure with double sided sticky tabs in the toilet)

 

Next the front lights are put in place and tested- then the motor bogie put back in before the PCB is put back in place.

These DMUs are wired a little differently than the conventional Fleischmann locos

Fleischmann locos generally are pushed (with the motor at the rear) and these are pulled (driver at the front and motor just behind him)
The motor body is connected to the Right hand rail pickups and the orange wire goes to the left hand side of the motor.



I paint all the visible wires black inside the cab area

I tend to leave enough wire for the motor to be pulled out for servicing so the extra is folded above the PCB

A few pictures of the motorized end

An Old Fleischmann Loco Converted to DCC

Hi All,

It's been a while since I added anything to my thread , although I have done quite a bit on modelling in between.

This loco I bought as a non runner a V60 or BR260 this is an early Fleischmann model #1380 with metal body
made between 1959-1966
They are just about indestructible.
The motor would not run, when I measured it with a multimeter - it looked as if the armature coils had shorted out.

Out with the trusty IPA, and a good clean, removing Carbon and oil residue from the commutator and between the gaps,
reassembled and tested and it ran trouble free and with quite a bit of power , the motor would run at quite low voltage without stalling - just as good as a new one. Not bad for something 50 years old.

The decoder for this one is the DCCconcepts M4-SA



Having all the function wires connected to the JST plug makes wiring much easier than the mini JST on the S4-SA



The loco was not quite complete having one set of lights missing - but we will replace them with some SMDs



A little forest of SMDs each pair wired in series (tested before hand)



Then tried in place



Neat without wiring



Decoder and Stay Alive in place





With all the SMDs and wiring in one piece it is just a matter of putting it in place on the loco



Then testing on the Programming track before trying on the main

I had the SMDs sticking out a little to far and broke one so a bit of patience and I managed to solder a replacement in (not easy!)





I also forgot to take Photos of the Red lights working

A Little Repair and Conversion Work

This is a Loco I did for a fellow MRF member a truly lovely BR74 by Roco (Don't look at the Flanges Richard!)
Runs very nicely on DC but had a broken or missing Pin on part of the Drive gear.



I made a New pin out of a off cut Aluminium from an LED tail soldered in place and filed to fit



Tested and worked a treat


A little paint to blend in with the rest of the Drive gear.

Same Loco, a bit later on I Did my first NMRA 8 Pin (NEM652) DCC Conversion
I normally Hard wire most of my conversions.

This a DCCconcepts Thin series (TS4-SA) Nice elegant decoder
Just compare it to the 8 pin plug and the DCCconcepts 8 pin plug is quite small compared to others that I have cut off the harnesses .

I shortened the harness quite a bit .



The decoder plugs in at the rear of the Loco , shame there is not enough room with the plug and socket plus extra components to fit the decoder under the cover there as well.



Below Decoder in place - just before a bit of black paint is applied.



Nice loco



One thing to note about resoldering the 8 pin plugs - If you have a socket to plug into it will keep the pins in place on the body of the plug

Or failing that - I used a blob of Blu-Tack as a "socket/ Heat sink" when I soldered the wires onto the plug

Fleischmann 5300 Weathering and Flicker Free SMD LEDs

Next little exercise I have on my workbench is a Fleischmann 5300 that needs a little modification. The Fleischmann 5300 does not come equipped with interior lighting or Red taillights that the 5301 does. Time to be creative and add lighting and a bit of weathering. The body comes of with a little bit of difficulty; there are 4 clips holding the interior plastic detail to the body and four clips holding the interior detail to the chassis. With a little patience, remove the body without breaking anything. Remove the wheels, weight and axle holders. Solder some wire on the axle holders to provide power for the  lighting. With the chassis separate, paint the chassis a dark brown as a base for the weathering.  I use a mixture of Tamiya Flat black and Hull Red thinned down by 50% with IPA, two quick coats will  give good coverage. Above: Note the colour of the chassis and the PCB board for the lighting.
SMD LEDs soldered to the Flickerfree PCB, Red SMDs on 1k Ohm resistors . I found an addition 1k Ohm resistor required to reduce the voltage to the Red SMDs. The Flickerfree PCB has a 510 Ohm resistor as the main resistance. The wire from the front wheel set has also been hidden under the interior detail.

Next, to create a cover for the Red SMD rear lights, cut some black card and bend in a U shape- slide it in over the SMD and glue in place with some CA.  The back of the “light fitting” filled in with some filler then painted flat black.

	Solder the wires from the axle pickups directly to the Flickerfree Unit inputs. Use the mounting tape tabs to secure the Flickerfree Unit to the floor of the interior.

Above: Weathering powders used to add some rusty dust colouring to the lower part of the body