Miniature Tramway

[mulberry50]

As a new member I would like to ask advice of more experienced model engineers.
I have made models of trams for many years, mainly in 1:16 scale. I now want to construct a passenger carrying line. My inspiration comes from the late Gordon Hatch, who pioneered a 15 inch gauge garden system. A look at the www.urban21.ca/streetcar%20models.htm website gives a good idea of the set up and the vehicles.
I have in mind to make a model of a four wheel demi car and then add a control trailer on which the driver could sit. The line needs to transport me and any future grandchildren (?) along the back garden. Overhead wire would be set at around six feet above rail level.
My restricted resources include a lathe and a pillar drill. Everything has to be done in a tight budget within my pension! I was wondering about materials for track, rails, electric motors etc. I live in East Sussex and have yet to explore the yards of scrap metal dealers.
I would be very grateful for any constructive advice.

[alanstepney]

You say you live in East Sussex, and mention a pension.

Therefore you are old enough and in the right place to have seen the tramway that ran along the Crumbles at Eastbourne adjacent to Princes Park.
(Later, it was removed and is now at Seaton.)

Apart from the information you already have, you may find some extra details from them.

The one concern I would have with the size and set-up you mention, is the voltage.
6ft high is low enough for someone to touch, so it would need to be a voltage that was "harmless", thus, to give the required power, high current.

[ilvaporista]

I think that the Cardiff club have (had) a tram set up. I'm sure someone on here can give more details.

[dscott]

I would look at a starter motor as a method of propulsion, and posible a third rail to carry the required voltage without the drop in current towards the end of the line.
The Cardiff club tram is great, even children can opperate it.
David.
Lover of tram engines as well.

[ilvaporista]

Starter motors are not designed for continuous operation being primarily designed for high torque in short bursts. There are some good DC motors around that will fit the bill. Old (1970's) windscreen wiper motors are good and wheelchair motors also. The Sinclair C5 had a good motor but they are like goldust now..

[teakfreak]

There was a shrt series in the Model Engineeron building battery electric vehicles using a rewired Lucas dynamo, driving through a Stanley hand drill bevel gears and lawnmower chains. I can probably find copies of these articles if these are of interest - send me a pm. I built an 5" 0-4-0battery engine, dressed up to look a bit like a de Winton narrow gauge engine for my children, based loosely on this design and it has worked well for several years.

[teakfreak]

I would agree that an overhead wire system might not be advisable - better to go for battery power. There was a short series in the Model Engineeron building battery electric vehicles using a rewired Lucas dynamo, driving through a Stanley hand drill bevel gears and lawnmower chains. I can probably find copies of these articles if these are of interest - send me a pm. I built an 5" 0-4-0battery engine, dressed up to look a bit like a De Winton narrow gauge engine for my children, based loosely on this design and it has worked well for several years. I used cnc turned wheels from Compass House (usual disclaimer) but if you have a lathe there shouldn't be a problem there.

[baggo]

Another more recent source of DC motors, certainly for smaller locos etc is the kid's electric scooter market. Motors for these often come on Ebay for a reasonable price and they are compact and powerful.
A chap in the 2.5" Association used one to build a little 0-6-0 shunter with the motor mounted vertically in the cab and the bevel gears from a cheap angle grinder to turn the drive through 90°. All axles are then chain driven. He often brings it to the rallies and everyone queues up for a go! It bombs around the track all day on one charge with no trouble at all.

For cheap track use ordinary black steel bar either welded to steel sleepers or fastened to wooden ones with screws. Using the commercially available stuff is very expensive, although you can often pick good stuff up s/h

John

[havoc]

A fairly standard starter motor will draw about 300A. You'll need serious batteries to keep that running for more than a few minutes.

I cannot find the site back, but I tought visiting a japanese site where a guy had set up a tramway around his house.

[steam4ian]

G'day Mulberry.

By now you should be confused

Overhead power collection is possible at voltages up to 110Vdc without major risk to persons. Under the Australian Wiring Rules this voltage is considered an "Extra Low Voltage" at which the risk of fatal shock from direct contact is low/negligible. For an ac system the corresponding voltage is 32volts (nominal). I am sure you will find similar wording in the IEE regulations used in the UK.

Regarding starter motors. Sure they draw 300amps when stalled, ie first moving a sluggish engine, but they are series wound and the current inherently reduces as the speed increases. But they would still need to draw 100 amps for maximum usable torque.

In days of yore auto generators were pressed into motor duty. In Oz a firm called Oatley Electronics offer a range of 24V motors up to 300watts. Google them and look at their web site. I am sure that there are similar outlets in other climes.

Traditionally traction motors have been series wound. However power electronic controls can allow shunt wound and permanent magnet motors.

Regards,
Ian

[Malcolm]

Try Parkside Electronics (Ad in Model Engineer). They do a lot of stuff for electric traction. I used two 200watt motors from them for my 5 inch gauge Blackpool tram which will pull several people at about 8mph on my club track. Battery though, the club don't like the idea of overhead wires!

[houstonceng]

Steam4ian

110V dc is definitely not safe and certainly not "SELV". 24V ac / 32v dc would be ok in the UK.

mullberry50

Forget the rewired car dynamo. Buy some permanent magnet dc motors (available from various suppliers advertising in ME, MEW and EIM or at exhibitions like Parkside). I rewired a couple for a fellow ModEng and he used the "controller" written up in the ME Tram article mentioned by teakfreak. He soon went to real motors and a 4QD controller.

[havoc]

I fear that with overhead wires the problem of voltage isn't the biggest problem. Going up to 72Vdc would keep you within most safety rules. At those voltages the problem becomes distance as the resistance of the wires isn't negligable anymore. And there is af course the problem of lightning. You will need to make sure that in case of a strike it doesn't burn down whatever is connected to it.

[teakfreak]

I have to admit that I didin't use the control system described in the ME article I referred to - friend built me an electronic controller, which cost me around £50 in parts and can be operated by a 2-year old - it has a button that has to be held down to go forwards and the same for reverse (and a third one for a horn, which has proved to be the most popular of the three!). I have the circuit diagram for this and can supply if required. The original inquiry mentioned the need for low cost, and the original system as described in ME can probably done for a fractioned of the priice of aQ4D controller.