"Automatic" points?

[Tony Marsh]

This is a question for anyone.  On two of the railway wagon tracks that lead to the canal from mines rather than the SMJ line or the main line there was a brake drum contraption that controlled the rate of descent of a full wagon down to the canal.  The full wagon's weight was utilised to bring up an empty wagon and halfway along the line, below the drum, there was a bifurcation in the railway track so that the two wagons could pass one another.  I described some of this on the Blisworth site at http://www.blisworth.org.uk/images/Mining/Blisworth_mining.htm.
Now, I wonder if the side-by-side tracks could have been equipped with automatic points so that a wagon, which ever one it is, will always "bear left" and so pass the other one without a man having to supervise the exchange.  So, folks, do you know of such "automatic" points invented circa 1865, ie. early enough to be of use for this job?
Tony Marsh

[George Coles]

Tony, it depends on whether the rope was continuous or not.
The more likely scenario is a discontinuous rope. In that case, to avoid tangling the rope at the passing loop, alternate wgons would use opposite sides of the loop. The point blades could either be loose (most likely) or held by an over-centre spring or an over-centre weighted lever. As an example, an upcoming wagon would meet the lower point set for the left hand road and the downgoing wagon would meet the upper point set for the right hand road (i.e. both would turn left with respect to their direction of travel.) As they left the loop, each would force the point through which it was passing to change to the opposite setting. As a result, the next pair of wagons would run through the right hand roads (in respect of their direction of travel) and as they exited the loop each would switch the points, so we end up where we started this example.
Some long inclines were worked with continuous ropes (running round a pulley at the opposite end to the winding/braking drum.) These were usually driven by power winches, and wagons were attached to the (often) moving rope with a length of chain hooked to the wagon and wrapped round the rope. In this case, the wagons always passed the same way through the passing loop, and the simplest way of achieving this would be to bias the point blades with a spring or a weighted lever thus allowing the points to be passed through from the 'wrong' road in the trailing direction.
I'd be happy to demonstrate this, or draw a diagram ;)
Hope this helps.
George Coles

[Tony Marsh]

George Coles said:

Tony, it depends on whether the rope was continuous or not.
The more likely scenario is a discontinuous rope. In that case, to avoid tangling the rope at the passing loop, alternate wgons would use opposite sides of the loop. The point blades could either be loose (most likely) or held by an over-centre spring or an over-centre weighted lever. As an example, an upcoming wagon would meet the lower point set for the left hand road and the downgoing wagon would meet the upper point set for the right hand road (i.e. both would turn left with respect to their direction of travel.) As they left the loop, each would force the point through which it was passing to change to the opposite setting. As a result, the next pair of wagons would run through the right hand roads (in respect of their direction of travel) and as they exited the loop each would switch the points, so we end up where we started this example.
Some long inclines were worked with continuous ropes (running round a pulley at the opposite end to the winding/braking drum.) These were usually driven by power winches, and wagons were attached to the (often) moving rope with a length of chain hooked to the wagon and wrapped round the rope. In this case, the wagons always passed the same way through the passing loop, and the simplest way of achieving this would be to bias the point blades with a spring or a weighted lever thus allowing the points to be passed through from the 'wrong' road in the trailing direction.
I'd be happy to demonstrate this, or draw a diagram ;)
Hope this helps.
George Coles

No, no need for diagram, I follow your drift. I am going to try uploading a 1920s picture of the points area by the drum and show you the drum as well. The camera is pointing up the main incline, a full wagon waits to one side before being used to raise the empty wagon that is waiting 200 yards down the incline. Can you work out what is designed to happen? Every atom in the photo is now dust and rust under tarmac and houses. Tony

[George Coles]

The shadows on the drum are confusing, but looking closely, the rope atached to the left half of the drum is deployed (to the empty wagon down the incline) and what appears to be another rope on the same side is the shadow of the actual rope. Confusingly, the shadow crosses the drum division close to where the almost fully wound rope on the right hand half of the drum leaves the drum. That rope is hooked up on the wall out of the way.
The points nearest to us are set for the road to the right of us, and are conventional taper bladed points. The set between those points and the full wagon are typical quarry stub points. The route through stub points is normally changed by the application of a size 9 to the blades.
Sequence of events:
1) Kick stub points over to allow full wagon to approach incline.
2) Push wagon forward (toward us) until it is past the drum. It will now be on the right hand track. Apply brake (shove a stick under/through a wheel if no other means available.)
3) Attach rope to far end of full wagon.
4) Release brake on wagon.
5) Presumably signal that all is ready.
6) Push full wagon on to incline.
7) Release drum brake and control speed of descending/ascending wagons using drum brake. Note that ropes are wound round drum in same direction, (i.e. one comes off the top and one comes off the bottom) so left hand rope winds in as right hand one pays out.
8) If empties are to go in to left side of loop beyond the drum, kick stub points back to position shown on photo.
9) Stop drum and apply brake when wagons have arrived at ends of incline.
10) Apply brake of empty wagon (see above for options.)
11) Detach rope from empty wagon, and hook on to left hand wall (or throw rope on left hand bank) out of the way.
12) Release brake and push wagon in to left side of loop.
13) Repeat sequence, but send full wagon down the road to the left of the picture.
George

[Tony Marsh]

George Coles said:

The shadows on the drum are confusing, but looking closely, the rope atached to the left half of the drum is deployed (to the empty wagon down the incline) and what appears to be another rope on the same side is the shadow of the actual rope. Confusingly, the shadow crosses the drum division close to where the almost fully wound rope on the right hand half of the drum leaves the drum. That rope is hooked up on the wall out of the way.
The points nearest to us are set for the road to the right of us, and are conventional taper bladed points. The set between those points and the full wagon are typical quarry stub points. The route through stub points is normally changed by the application of a size 9 to the blades.
Sequence of events:
1) Kick stub points over to allow full wagon to approach incline.
2) Push wagon forward (toward us) until it is past the drum. It will now be on the right hand track. Apply brake (shove a stick under/through a wheel if no other means available.)
3) Attach rope to far end of full wagon.
4) Release brake on wagon.
5) Presumably signal that all is ready.
6) Push full wagon on to incline.
7) Release drum brake and control speed of descending/ascending wagons using drum brake. Note that ropes are wound round drum in same direction, (i.e. one comes off the top and one comes off the bottom) so left hand rope winds in as right hand one pays out.
8) If empties are to go in to left side of loop beyond the drum, kick stub points back to position shown on photo.
9) Stop drum and apply brake when wagons have arrived at ends of incline.
10) Apply brake of empty wagon (see above for options.)
11) Detach rope from empty wagon, and hook on to left hand wall (or throw rope on left hand bank) out of the way.
12) Release brake and push wagon in to left side of loop.
13) Repeat sequence, but send full wagon down the road to the left of the picture.
George

That's a neat piece of detective work! I take it that the plainness of the points in the photo indicate they are operated manually. You suggest the full wagon should always go down the same side? That means the ascending wagons use exclusively the other side and the design of the lower points would be one of those you have already described. The evidence for sorting out how this drum was used has been with us for decades. It's remarkable that I saw fit to inquire about automatic points before looking at the photo. I think I need to correct what I have written in the mining article on the Blisworth site. I hope you wouldn't mind my pasting your words for that because I appreciate very much your sorting out the ideas? I like to give a decent acknowledgment so can I say something appropriate like "railway engineer" or retired engineer" or "author of . . . ." (guessing!) as well as member of the SMJ Soc. By the way - what is a No. 9, I would have thought a plate-layers boot was bigger than size 9. best regards Tony Marsh

[George Coles]

Sorry, I don't seem to have made it too clear after all that. Activity 13 refers to wagons descending/ascending the incline (to this side of the overhead drum.) They would have alternated between the two tracks. Activity 8 refers to wagons being moved to/from the incline (i.e. at the far side of the drum from us.)
I was guessing at size 9s; my impression is that they were only little fellows in thos days ;)
You could say 'ferroequinologist' or even 'railway enthusiast.' I prefer the former!
If I can help in any other way, please ask. Regards, George

[Andy Thompson]

Tony Marsh said:

George Coles said:

Tony, it depends on whether the rope was continuous or not.
The more likely scenario is a discontinuous rope. In that case, to avoid tangling the rope at the passing loop, alternate wgons would use opposite sides of the loop. The point blades could either be loose (most likely) or held by an over-centre spring or an over-centre weighted lever. As an example, an upcoming wagon would meet the lower point set for the left hand road and the downgoing wagon would meet the upper point set for the right hand road (i.e. both would turn left with respect to their direction of travel.) As they left the loop, each would force the point through which it was passing to change to the opposite setting. As a result, the next pair of wagons would run through the right hand roads (in respect of their direction of travel) and as they exited the loop each would switch the points, so we end up where we started this example.
Some long inclines were worked with continuous ropes (running round a pulley at the opposite end to the winding/braking drum.) These were usually driven by power winches, and wagons were attached to the (often) moving rope with a length of chain hooked to the wagon and wrapped round the rope. In this case, the wagons always passed the same way through the passing loop, and the simplest way of achieving this would be to bias the point blades with a spring or a weighted lever thus allowing the points to be passed through from the 'wrong' road in the trailing direction.
I'd be happy to demonstrate this, or draw a diagram ;)
Hope this helps.
George Coles

No, no need for diagram, I follow your drift. I am going to try uploading a 1920s picture of the points area by the drum and show you the drum as well. The camera is pointing up the main incline, a full wagon waits to one side before being used to raise the empty wagon that is waiting 200 yards down the incline. Can you work out what is designed to happen? Every atom in the photo is now dust and rust under tarmac and houses. Tony

[Tony Marsh]

George Coles said:

Sorry, I don't seem to have made it too clear after all that. Activity 13 refers to wagons descending/ascending the incline (to this side of the overhead drum.) They would have alternated between the two tracks. Activity 8 refers to wagons being moved to/from the incline (i.e. at the far side of the drum from us.)
I was guessing at size 9s; my impression is that they were only little fellows in thos days ;)
You could say 'ferroequinologist' or even 'railway enthusiast.' I prefer the former!
If I can help in any other way, please ask. Regards, George

George, thank you very much and on re-reading I realise it was all there the first time! Just one thing now strikes me - why is the drum not divided into two more-or-less equal sections. The right-hand section appears to have more steel rope on it than could be comfortably wound up onto the left-hand section. That's curious. Tony

[George Coles]

Tony. I thought it was odd when I first saw the picture. The only suggestion I can make, without any confidence, is related to the position of the drum over the tracks, and the angle of the tracks away from the drum. My thought here is that the left drum may have to spool in over a much wider angle, but ultimately the left track must pass beneath it, whereas the right drum is more in line with the right track and its spooling is less likely to cause problems (i.e. offset pulls resulting in derailments.) As I said at the start of this note, I really do not know.
George