R070 Hornby Turntable - on a DCC layout

[dave flint]

I'm tempted to get a R070 Turntable for a Thomas based kiddies layout, which will be controlled via DCC.

 

It seems easy enough to wire a decoder in to control the motor, but I'm struggling to find the best way to ensure that the track doesn't short circuit when in use.

 

I did a search on this site, and didn't bring up much, but Google brings up a huge range of replies. Basically, they're

 

1) Take out the brass contacts from the turntable (Hornby's official advice) and feed the tracks radiating from the ttable.

2) Put some isulating tape over the contacts so they don't work

3) Buy a "thing" off ebay to avoid short circuits

 

One other point. Does anyone know how the table itself is wired? I'm wondering what will happen when a loco is driven on, and then turned through 180 degrees to come back off again. Is it a slip ring ? I'm not bothered about the loco losing the track power supply whilst turning as I don't want them to move whilst the ttable is moving and they wont have lights or sound on them anyway.

[smokebox]

I don't think there is a definitive answer as one single modification won't suit everybody.

Those with sound fitted locos, for instance, may not be happy with the sound cutting out while the turntable is rotated, which is what happens with some (if not all?) of the simple, cheap methods. In this instance an auto reverse unit may be called for to keep the bridge rails live at all times.

In my own experience, removing the brass contacts was a must, as they soon got mangled.

[dave flint]

I can see this being the simplest course of action for this application.

 

Any idea how the power feed to the ttable works, if i turn a loco through 180 degrees ?

[7013]

The Hornby site does have a fairly comprehensive conversion diagram for the Hornby turntable, Also if you look at Brian Lamberts site he has a very comprehensive section on wiring a Peco turntable.

[HLT 0109]

Dave,

 

I gave up on the Hornby turntable for a number of reasons but, although my layout is DCC, I operated the turntable via analogue with the standard switch. There was no problem with reverse polarity - the arrangement of the contacts underneath the bridge prevented it - but there was no power to the bridge rails while they were being turned. What I would say if you intend to incorporate that unit is, make sure that your locos approach the bridge dead straight or they may derail as they cross from the approach to the bridge - I found that I could only get good rail-alignment in one direction; when the rotation was reversed, the alignment was a long way out. If the locos appraoch straight on, the tolerance can be set in the middle.

 

Harold.

[tender]

Hi Dave, I have a Hornby turntable already converted to DCC for sale complete with decoder. Converting to code 75 track so surplus to requirements. £30 plus P&P, PM me if interested.

Ray.

[dave flint]

Thanks, but we're weighing up options at the moment. I've found another dad who's "a bit keen" on getting a layout sorted for our boys.

 

Will bear it in mind though.

[dave flint]

A little more digging and I've found the following....

 

I'm using DCC and all I have done is removed all 4 copper contacts at the end of the bridge rails.

 

All the tracks into and out of the TTable are connected to the powerbus.( powerbus:- two cables that run below the baseboard around the layout. Feeder wires are soldered to the side of each rail and drop through the baseboard and soldered to the powerbus. The DCC controller output is then connected to the powerbus)

 

Underneath the Turntable you can see two wires from the centre going out to the track infeed, I have disconnected these and soldered them again to the powerbus. This means the rails on the turntable bridge are always live. I just made sure that in the position where the engine enters the TTable the bridge rails are on the same powerbus wire as the infeed track.

 

This allows the engine to be driven onto the bridge.

 

All works perfectly, as the turntable rotates, once it gets past 180degress the polarity reverses, this does actually reset the sound though on a sound chipped loco, but no short circuits and no need for a reverse module or track adapter.

 

 

 

 

This answer my questions about the power to the turntable itself. As long as all inlet/outlet tracks and the ttable are connected to the same bus, then there seems to be no problem. It's probably the simplest solution to this problem.

 

 

 

 

Now to borrow a router to nibble away at the baseboard.........

 

[locoworks]

Thanks, but we're weighing up options at the moment. I've found another dad who's "a bit keen" on getting a layout sorted for our boys.

 

Will bear it in mind though.

 

 

'a bit keen' = wants it finished yesterday

[chargeN]

I have converted to dcc. Although turntable rotates, having followed advice re pickup removal there is no power on the tt deck. Any suggestions?

[Deev]

Could you fit a reverser loop auto module that automatically switches polarity in series with the DCC supply to the turntable?

[Krazykrisbell]

Hi

I have a Hornby TT wired up on my DCC layout , connected to a loco decoder. I have a Z21 command station and am using Rocrail to control everything.

The TT works fine , as a loco, but ideally I would like to be able to configure my TT yhrough Rocrail but I don't know how to.

Anyone got any ideas?

[RAF96]

Have you asked on the Rocrail forum, although you may take flak for playing with ‘Hornby toy railway parts’.

As I remember it Rocrail has a comprehensive manual and no doubt it is covered in there somewhere.

Maybe a diplomatic question to that forum could be ‘ I want to operate my Hornby TT using Rocrail and my Z21 but cannot find it in your excellent manual - could you please give me a link to the correct section, etc’.