Sensible working load for 71/4" Dart.

[David Powell]

I have recently purchased a 71/4" Gauge Dart in full working order. She is alleged to weigh about 300 lbs. Given the rather unusual wheel arrangement 0-4-2 I wonder what would be a sensible maximum load to expect her to pull without excessive wheel slip. Can anyone with experience of this or similar models give any advice. Regards David Powell.

[Fred_V]

The Allen Chloe is similar but weighs about 200#. It will pull 3 to 5 cars up a grade. I could pull 3 adults and a kid or two up a grade with mine.

[Steve Goodbody]

Hi David,

Back in the 80's I used to regularly drive a Dart on public passenger hauling duty around a park in the UK, the ruling gradient was 1 in 80. We ran with two heavy passenger cars each capable of carrying up to five adults or seven kids, hence a maximum load of 11 adults including driver.

The loco would certainly haul more than this in ideal conditions. I know we tested that out but can't remember how many we loaded up - probably another car with five adults hence 3 cars and 16 adults total. However two cars full of adults was the realistic limit that the loco could re-start with care if the train was held at a signal on the bank and the track was wet. We ran a pretty intensive multi-train service and tried to minimize holdups.

It was a fantastic loco that would happily run around all day making steam like crazy, I am sure that you will have a lot of fun with it.

Best regards
Steve

[LVRR2095]

David;
Could we see a photo of the Dart?

Keith

[Bill Shields]

there are the age old questions that nobody is asking:

1> aluminum or steel rail?
2> cast iron or steel tires on the drivers?

knowing this, you can figure the adhesion (dry rail) and work backwards to what is expected based on weights and starting / rolling friction of the cars -> (assuming that the loco does not just plain STALL).

[David Powell]

Steel rails, cast iron wheels, and from the way she runs jacked up there will not be any question of stalling lacking power, My main concern was that weight transfer when pulling hard will reduce grip enough to make nonsense out of theoretical loadings. As yet I do not have a single photo of her and she is packed up in the trailer ready to go to the Frontenac Society of Model Engineers event as part of the Battersea Pumpkin Festival ( Near Kingston Ontario Canada) to be held on Saturday Ist October. A previous posting was very encouraging regarding a Dart's capacity. I rather hope that she will not be needed to handle the public running, but I want to be as prepared as possible just in case. Thanks to all who have responded so far. David Powell.

[Steve Goodbody]

To clarify based on Bill's comments - the Dart mentioned in my post also had cast iron drivers and was running on steel rail. The engine in question can be seen here:
http://www.bentleyrailway.co.uk/locopics.php?loco=15

Best regards
Steve