Conversion advice please...

[trucknightmares]

It is possible to convert the following locos to dcc:

 

Class 08 shunter

Photos: https://drive.google.com/folderview?id=1-8MuSPknLRSNq7fAF_Xw8VdZIlb2Rz2B

 

Class 47

Photos: https://drive.google.com/folderview?id=1-9Dp6TYlsc8TLfAkDeHpKUiZ7ZFjsgM3

 

Class 86 (with working pantograph)

Photos: https://drive.google.com/folderview?id=1-Ihm1fI-i6IUBjBwhWAwthTEeyh_ixyP

 

Although they've been in storage for last 20+ years, all still work on an analogue layout.

[mikeg]

 The simple answer is yes, have a look on the decoder install section of this forum and you will find a lot of useful information. You have to select the right decoder for the current draw of the loco, many of the older locos need 1-1.5amp capacity and there are many to choose from.

Have a look on Digitrains or Coastal DCC websites for the ranges available.

 

 Regards mike 

[RAF96]

Essentially you need to be able to isolate the motor brushes from the wheel pickups, then as stated you need to establish the motor stall current and choose a suitable decoder that can handle this current.

 

There are several methods of isolation dependant upon the model and motor, either live chassis, split chassis, ringfields, etc.

[Phil S]

i would strongly recommend buying a multiimeter if you do not already have  one....  for simple continuity ( or non-continuity  i.e. isolation ) a cheap meter will do. 

 

You will then be able  to check,  as mentioned by raf96, that both motor connections are totally isolated from both rails/pickups before connecting a decoder in between.

Also - whilst stll on dc/analogue ... measuring the current talken  BEFORE deciding which decoder to buy for the loco. 

 

[on the resistance ramge, you can also measure the resistance of the isolated motor  ... somewhere about 10 ohms .... and as you rotate the motor by hand ( if possible), you will see the commutator switching each coil in and out of circuit .... so you will sometimes see the resistance drop [halve] as 2 are briefly  in parallel.  V = IR ....  I = V/R is then a guide to the stall current at startup. crude example   if R=10, trackdccV =10   I = 10/10 = 1amp      if R=20  track dcc = 15V ac  I =  15/20 = 0.75A

 

.... but be aware that if used to measure the 'actual' dcc voltage [ on the a.c. range ] a cheapish digital meter  will probably give the wrong value ... but can still be used for relative comparisons around a layout.  (This is because the digital meters use 'sampling' to measure the voltage, and many assume that this is for a sinewave),, not 'square'.

[JST]

As you have seen, it is quite possible. However, you need to ask yourself why do it. I have been in exactly the same position with a lot of my old locos. I wanted to convert them to DCC to run on my layout mainly for nostalgic reasons and have had some excellent results particularly with my old Wrenn West Country and some old Bachmann split chassis locos. However, my Hornby and Airfix tender drive locos are not great. The bottom line is that new locos just run better so much so that the old locos tend to sit in the loco shed/yard while the new ones do the running.

 

I have fitted a couple of Lima locos with CD tray motors and they run superbly and I think that this conversion may also be possible for Hornby tender drive locos.

[trucknightmares]

Thanks for the advice guys, I think if I'm going to convert any of then, it'll more than likely be the 08.

[Ron Ron Ron]

As JST says, why do it?

More modern models of these three prototypes, knock spots of those old things, in looks, detail and running.

[trucknightmares]

You're probably right, the amount is spend to convert it, would prob get me a decent secondhand model!