gregh
electronics, computers and scratchbuilding
I built this Garratt back in 1998. It was my first attempt at scratchbuilding.
(note the 2nd Big Blue Garratt behind ? I like Garratts!)
It is based on two Bachmann 2-4-2 Lynton & Barnstaple ?Lyn? locos. It turned out these motors are quite low voltage but high current types. Each motor takes 1.5 amps but only needs about 6V or so for reasonable (Garratt) speed. When I built it I had no track controller capable of providing 3 amps, so I wired both motors in series. I put in a 7V NiCd battery to power the sound while stopped. But over the years I converted all my locos to battery power RC and the Garratt became an orphan and for the last few years it sat on a shelf in my shed.
When I went to use it recently, ALL the wiring had been affected by this horrible black corrosion. Apparently it starts on the negative battery terminal and works its way along the wires.
Anyhow, while rewiring, I decided to put in RC using my now standard Hobbyking 2.4 GHz stuff.
The 2 tanks already had the 2 sound units in them, so I had to put the batteries and RC stuff in the boiler. I had planned to use two parallel banks of four NiMH cells and put the motors in parallel, BUT luckily I realised in time that this 6V would not be enough for loud sound. So I used 10 cells in series (13V) and left the motors in series.
The 2.4 GHz Rx, ESC and servo for reversing, as well as the batteries, are mounted on a sheet of styrene.
A HobbyKing 6 channel RX, 20A ESC and micro servo with DPDT switch are used. The reversing DPDT switch is superglued to the servo and another SPDT switch glued to it for the head/rear lights control. All 3 elements are hot glued to a piece of 1.5mm styrene. (right end of pic)
The battery cells are all soldered together, but to try to stop the black corrosion I used a 1 cm long brass rod on the neg terminal and put the Polyswitch (?fuse?) in the negative, and covered well with Vaseline. Only 5 years will tell if it works !
As you can see from the pic, I am not the most tidy electrical wirer.
The 2300 mAh cells will probably only give about an hour's continuous run, but it meandered around on and off for 2 hours today. Better than sitting on the shelf!
There?s a short video on Youtube here:
http://www.youtube.com/watch?v=le8quQV2YOM < Link To http://www.youtube.com/watch?v=le8quQV2YOM
(note the 2nd Big Blue Garratt behind ? I like Garratts!)
It is based on two Bachmann 2-4-2 Lynton & Barnstaple ?Lyn? locos. It turned out these motors are quite low voltage but high current types. Each motor takes 1.5 amps but only needs about 6V or so for reasonable (Garratt) speed. When I built it I had no track controller capable of providing 3 amps, so I wired both motors in series. I put in a 7V NiCd battery to power the sound while stopped. But over the years I converted all my locos to battery power RC and the Garratt became an orphan and for the last few years it sat on a shelf in my shed.
When I went to use it recently, ALL the wiring had been affected by this horrible black corrosion. Apparently it starts on the negative battery terminal and works its way along the wires.
Anyhow, while rewiring, I decided to put in RC using my now standard Hobbyking 2.4 GHz stuff.
The 2 tanks already had the 2 sound units in them, so I had to put the batteries and RC stuff in the boiler. I had planned to use two parallel banks of four NiMH cells and put the motors in parallel, BUT luckily I realised in time that this 6V would not be enough for loud sound. So I used 10 cells in series (13V) and left the motors in series.
The 2.4 GHz Rx, ESC and servo for reversing, as well as the batteries, are mounted on a sheet of styrene.
A HobbyKing 6 channel RX, 20A ESC and micro servo with DPDT switch are used. The reversing DPDT switch is superglued to the servo and another SPDT switch glued to it for the head/rear lights control. All 3 elements are hot glued to a piece of 1.5mm styrene. (right end of pic)
The battery cells are all soldered together, but to try to stop the black corrosion I used a 1 cm long brass rod on the neg terminal and put the Polyswitch (?fuse?) in the negative, and covered well with Vaseline. Only 5 years will tell if it works !
As you can see from the pic, I am not the most tidy electrical wirer.
The 2300 mAh cells will probably only give about an hour's continuous run, but it meandered around on and off for 2 hours today. Better than sitting on the shelf!
There?s a short video on Youtube here:
http://www.youtube.com/watch?v=le8quQV2YOM < Link To http://www.youtube.com/watch?v=le8quQV2YOM
