Fitting Sound to Bachmann LNWR Precedent

[zr2498]

I wish that I had read the LNWR Precedent thread on RMweb before starting this project!

 

 

It ran very well on DC, but when adding a decoder it behaved 'badly'.

Of course, by that time the model had been well and truly modified, so there was no turning back.

 

There is litte room in the tender for a large, or even medium sized speaker but I did manage to fit a second speaker, and a stay alive.

 

Here is the kit used.

 

First job though was to replace the traction tyres.

Keeper plate removed.

 

 

Traction tyre removed.

 

 

New wheels installation. I had to use some Zap Z-42 thread locker when refitting the crankpins as the thread was quite worn.

 

 

Inside the tender.

 

 

First task was to cut out the lower coal load. The upper load which is die cast fits over top and adds useful weight.

 

 

 

The stay alive was soldered to the ESU decoder, and then a trial fit into the tender of the capacitor and interface chip.

 

 

New wires were soldered to the sugar cube speaker. Note that the original pre-fitted speaker which is under the PC board was kept in place. The second speaker was wired in parallel.

 

 

Getting even this small speaker to fit, was done by having a small styrene strip for it to be supported.

 

 

And then fixing by black tac, placed at an angle as shown.

 

 

The original 'small' stay alive was replaced by a 'medium'.

 

 

 

Tender body refitted.

 

 

And coal load added.

 

 

Now for the testing and tuning.

The kit worked, but as previously mentioned it was dire running.

So it took a couple of hours of adjusting the drive (back emf) parameters to suit the coreless motor.

These were the final CV values.

 

 

Much better, especially at slower speeds.

The sound is OK, but there is a limit to what can be achieved with such small speakers. The functionality and the sound profiles from Wheeltappers are excellent. Note that both Wheeltappers and another couple of other sound suppliers use the Coal Tank sound files for the Precedent.

 

I wanted a suitable locomotive to pull the excellent Genesis LNWR coaches from Hattons.