Model Railway Forum

Hi,

I have a Bachmann class 40 Diesel to which I fitted a Hornby TTS sound chip to some time back, and with a speaker upgrade it sounds great. There is a problem however when it is on the layout and I get a short somewhere ( ie another loco going against wrong facing points), as it takes off like a banshee until it invariably collides with something.

I have already adjusted CV29 to eliminate DC running and I am now at a loss as to what to further adjust.........I am sure I have seen this covered somewhere else previously but cannot recall where........any thoughts ?

Thanks Richard

PS - As an aside, I also wanted to give the wheels a good cleaning ( as the loco has been weathered and there is some overspray), but cannot see how to remove the wheel sets without likely snapping the bogie frames........I came across the same problem on my Bachmann Deltic and ended up playing safe and cleaning in-situ.........Is there something obvious that I am missing ? thanks

Never any need to remove wheels for cleaning. Just clean them in situ. If the wheels are powered apply a PP3 battery to them and clean them as they spin. If not use finger power.

A battery on this loco won't work as DC operation has been disabled via CV29. CV29 would have to be adjusted again to turn On DC operation for a battery to be used.

Simplest IMO is to apply a pair of fly lead wires to the pick up wheels and the other end of the wires is connected to the DCC powered rails or Track output of the DCC system, this will turn the wheels once the correct loco address has been entered and the speed knob turned up etc. It will turn wheels while the fly wires bared ends are held in place on the wheel treads so as the others can be cleaned but its then really a two person job - One holding the two fly lead wires on the wheels while the other person cleans the now rotating wheels.

Using a powered wheel cleaner that's connected to the DCC system is easier IMO. Such devices for example are ... the Peco PL-42 or the Gaugemaster GM60 OO powered wheel cleaner. These are just two examples of powered wheel cleaning devices. Examples...
PL-42 example
GM60 example

In addition, I would connect at least one and if you're using a radial DCC Bus pair then two Bus Filters, these as will help remove any spikes/surges on the DCC system due to short circuits occurring.. They are simply made from just two components and should cost less than £0.50p per filter to make yourself. See link to Filters They are also available ready made too!

I use one of these, similar to Gaugemaster version. Easy to use and available cheaper if you look around. Works on any system, DC or DCC.

https://www.ebay.co.uk/itm/261869104856

Sorry Brian didn’t have my DCC head on. Rest applies though.

teedoubleudee wrote: ↑Fri Jun 11, 2021 10:22 am I use one of these, similar to Gaugemaster version. Easy to use and available cheaper if you look around. Works on any system, DC or DCC.

https://www.ebay.co.uk/itm/261869104856

I have one of these, but cleaning the brushes is a right royal PITA! I've not solved it so resort to other methods as described above.

IanS wrote: ↑Fri Jun 11, 2021 11:20 am

teedoubleudee wrote: ↑Fri Jun 11, 2021 10:22 am I use one of these, similar to Gaugemaster version. Easy to use and available cheaper if you look around. Works on any system, DC or DCC.

https://www.ebay.co.uk/itm/261869104856

I have one of these, but cleaning the brushes is a right royal PITA! I've not solved it so resort to other methods as described above.

Clean the brushes ?, i have used one for years, very little dirt on brushes. Just pull out the brush and soak in IPA.

Thanks for all the responses.......I am generally familiar with what's commercially available and how to clean wheels in-situ, but would still like to try to understand how to get them out of a Bachmann diesel if possible.

Brian - thanks for the detailed info on DCC Filters, I will look to get one fitted asap but still curious why only this loco behaves in this manner......I think it is definitely linked to the sensitivity of the TTS decoder.

Cheers - Richard

Richard, Most diesels need the complete bogie removing to get to the wheel sets, then the frame carrier removing. Only try this if you feel confident.

Hound Dog wrote: ↑Fri Jun 11, 2021 6:45 pm Thanks for all the responses....... <SNIP>
Brian - thanks for the detailed info on DCC Filters, I will look to get one fitted asap but still curious why only this loco behaves in this manner......I think it is definitely linked to the sensitivity of the TTS decoder.
Cheers - Richard

It is always a decoder issue! Some are better than others at withstanding surge spikes on the rails/Bus.
Some decoders and mainly budget decoders suffer more.
The Hornby TTS range can only at very best be considered as a Budget range!