A sanity check please chums,
being late at night and nowt on the box I thought I'd play with a plank !
rising from the bottom end at 34mm above datum ( ahem! posh way of describing the table top ! ) to about 75 mm at the top end over a bit of 55flextrack of about 80cm does this look right :
75-34 ~= 40
40/800 = 1/20 = 5%
nah, cant be cos the wee 4F has no bovver hauling 6 wee peco wagons upit
cos I think I have read that 3% +/- is what one should aim at?
Where have I gone wrong, what should I experment with on the morrow, in the cold light of day (and a google) , to be more scientific ?
Calculation looks fine to me.
My Peco wagons weigh not much more than a fly and I expect yours do too.
Would be interesting to see how steep you can make your ramp before a no go occurs.
Webbo
Nowt wrong with the maths and although 2 or 3% is suggested as ideal. I have an incline of 50mm in about 900 and everything goes up that OK.
Thanks webbo and malc,
yer, interesting !
There was a bit of a slippage at first but that was cos the thin plank (plank ! actually the side wall of a discrded chepo bookshelf ! ) was slightly bowed so the loco at the head was on a steeper bit of inline than the wagons behind, but a bit of packing soon sorted that out and returned things to a Galilean principle ;) So I may actually, on that basis, not be far from the limit ! But thoughts for the morrow continue (well it keeps one off the streets ;) )
Hmmm
Being as how I was getting on for 2x the usual suggested incline, and with a 4F that sometimes has a less than ideal reputation for haulage, I thort I'd better check that I wasnt having a senior moment !
Thanks chums, , ,
Slippage at first might in part or even mainly due to the loco needed to overcome its own inertia (and wagon inertia) before it gets going. You'll probably find that the loco can pull more up the slope if it can run onto the incline and not have to start on it.
What can pull what up a given incline is of major interest to me also. I've a section of track that has a 1.6% grade. I had a Farish black 5 that had a great deal of trouble pulling 6 Farish Stanier coaches up it. The loco was a tender drive and had a light weight tender with only a small space to add extra lead. Traction is all about weight over the driving wheels and the black 5 simply didn't have enough of it to pull its train along my mainline so it had to go. The 4F should do a fair better than this I expect.
I have a Kato SD40-2 (6 axle diesel) that will pull at least 17 grain hoppers up the hill by itself without problem (no traction tyres). Each hopper weighs about 50% more than a Farish mk1 coach. The Kato has a split frame and its body is mostly filled with metal. There is no substitute for weight when it comes to traction.
Webbo
Quote from: Webbo on April 23, 2015, 11:04:13 PM
inertia
Thanks for all your thoughts.
Yes very good point about inertia ! I shudav thort of that, but it was late at night over here :)
I chose 6 wagons for the initial experiment because my thoughts had turned to the classic Gumstump, always liked that idea, and 6 wagons would be 2 or 3 more than really needed.
More
playings experiments laters.
Quote from: Malc on April 23, 2015, 11:23:18 PM
50mm in about 900
5.5% , that is very respectable.
Perhaps instead of listing all our cars and motorbikes we should be experimenting on and listing all our locos' performances :)
I think we may need to co-opt a committee to spec an NGF standard variable incline :laugh:
I think some ropes pulleys and a clinometer may be needed, hmmm, there may even be a tilt app for these newfangled 'phones ?!
Quote from: MalcolmAL on April 24, 2015, 09:05:34 AM
Quote from: Malc on April 23, 2015, 11:23:18 PM
50mm in about 900
5.5% , that is very respectable.
Perhaps instead of listing all our cars and motorbikes we should be experimenting on and listing all our locos' performances :)
I think we may need to co-opt a committee to spec an NGF standard variable incline :laugh:
I think some ropes pulleys and a clinometer may be needed, hmmm, there may even be a tilt app for these newfangled 'phones ?!
I'll second that. For those of us who like ups and downs on our layouts such info would be useful before buying a particular loco.
Happy to engage in a discussion about how best to do this or come up with a standard test.
Webbo
I do wish they would go back to 1 in xx instead of % for inclines, much easier to understand.
Best puller I have is a Langley S15 kit on a Fleischmann chassis, ran out of coaches at 42 Farish Mk1s most on a 1:60 gradient (layout was 21'x17')
Quote from: Dorsetmike on April 24, 2015, 09:46:26 AM
I do wish they would go back to 1 in xx instead of % for inclines, much easier to understand.
Me too :thumbsup:
1 cubit in several is plain, % requires some math ability, just obfuscates things !
In my field of electrikery and telecomms the IEE and other bodies changed cycles per second into Hertz. Wots a Hertz evereone else asks ! So, you cant be a member of the club any more unless you have done 'our' degree course in Maxwell's equations, grrrr.
Oh dear I seem to have digressed :)
seriously though Mike raises a good point for the committtee's contemplation - How to specify the load.
No,,, maybe that should be a sub clause.
The first question perhaps should be - Loco alone or Loco plus Load.
If loco alone then two possibilities, (1) an inclined plane, or (2) a string on its tail over a pulley at board edge and a suspended pan upon which to place weights.
No, , again ,, ! :) Firstly the committee must rule upon the
advisability of stall testing, might this damage our locos ????
Nurse, nurse, he's been thinking again, pills needed
I always thought that they called it hurts because if you put your fingers across 50 Hz at 250 volts, it sure does.
Quote from: MalcolmAL on April 24, 2015, 10:39:12 AM
Quote from: Dorsetmike on April 24, 2015, 09:46:26 AM
I do wish they would go back to 1 in xx instead of % for inclines, much easier to understand.
Me too :thumbsup:
Am I missing something?
1% is 1 in 100
2% is 2 in 100
3% is 3 in 100
Doesn't seem hard?
How is it different to saying:
1 in 12, but I want to go up 2 units, so 2 x 12 is 24.
Numberwork either way, but at least % is easily turned into decimals and worked out on a calculator.
Cheers, NeMo
Quote from: MalcolmAL on April 24, 2015, 10:39:12 AM
Quote from: Dorsetmike on April 24, 2015, 09:46:26 AM
I do wish they would go back to 1 in xx instead of % for inclines, much easier to understand.
Me too :thumbsup:
1 cubit in several is plain, % requires some math ability, just obfuscates things !
In my field of electrikery and telecomms the IEE and other bodies changed cycles per second into Hertz. Wots a Hertz evereone else asks ! So, you cant be a member of the club any more unless you have done 'our' degree course in Maxwell's equations, grrrr.
Oh dear I seem to have digressed :)
seriously though
Mike raises a good point for the committtee's contemplation - How to specify the load.
No,,, maybe that should be a sub clause.
The first question perhaps should be - Loco alone or Loco plus Load.
If loco alone then two possibilities, (1) an inclined plane, or (2) a string on its tail over a pulley at board edge and a suspended pan upon which to place weights.
No, , again ,, ! :) Firstly the committee must rule upon the advisability of stall testing, might this damage our locos ????
Nurse, nurse, he's been thinking again, pills needed
[smg id=24347 type=preview align=center width=400]
:D :thumbsup: :beers:
When one has been used to using 1 in x, and rail gradient posts are 1 in xxx and knowing how steep that is, having to stop and think that 12% is about 1:8, and having been forced into all things metric, measures and money, one begins to wonder what next are they going to meddle with?
Everybody having to learn a common language, not be allowed to wear national dress, or prepare national cuisine?
So it makes it easier to have everybody in the world singing from the same (metric) hymn sheet, but where does one draw the line?
Quote from: Dorsetmike on April 24, 2015, 01:55:32 PM
When one has been used to using 1 in x, and rail gradient posts are 1 in xxx and knowing how steep that is, having to stop and think that 12% is about 1:8, and having been forced into all things metric, measures and money, one begins to wonder what next are they going to meddle with?
Last time I went driving, gradients were on the signs as a percentage. So surely road sign gradients are more familiar than railway line posts? I know we're modelling trains, but are you sure more of us a train drivers than car drivers???
Quote from: Dorsetmike on April 24, 2015, 01:55:32 PM
Everybody having to learn a common language, not be allowed to wear national dress, or prepare national cuisine?
Not sure I see a connection here. Decimalisation of numerical quantities has been going on for centuries, and generally, in a world that uses computers to do calculations, that's a good thing.
Quote from: Dorsetmike on April 24, 2015, 01:55:32 PM
So it makes it easier to have everybody in the world singing from the same (metric) hymn sheet, but where does one draw the line?
Challenge for you: explain why a non-decimal system be better than a metric system? There actually are some situations where it is, and I like explaining them when teaching history of science classes. But most people who argue against decimalisation and metrification do so because they are familiar with the Old System and don't like the New System. They find it hard to actually justify that intellectually. But I'm going to invite you to do so, Dorset Mike!
Cheers, NeMo
A % number is not decimal nor imperial.... is a proportion, by definition it does not mean any "unit"... 5% means anything you want it to mean, five inch each 100 inches or 5 cm each 100 cm... the choice of units is yours.
Regarding railway signals... modern HS lines in Spain express gradients in %
I remember reading a post script in one of Terry Pratchett's disc world books where he explains old British Imperial currency for young or American readers.
He starts off by saying 2 half pennies make one penny, three pennies make a threepenny bit, two threepenny bits make six pence.... He ends up with one pound and one shilling make a guinea. The general public were afraid of decimalisation.
Quote from: Malc on April 24, 2015, 03:31:09 PM
I remember reading a post script in one of Terry Pratchett's disc world books where he explains old British Imperial currency for young or American readers.
He starts off by saying 2 half pennies make one penny, three pennies make a threepenny bit, two threepenny bits make six pence.... He ends up with one pound and one shilling make a guinea. The general public were afraid of decimalisation.
Loved the quirky old LSD! I was the 'decimilisation officer' for my employers when the Big Change happened and converted thousands of prices in a 300 page catalogue to the new system.
I still find it fun converting back to pounds shillings and pence every now and then but finding it's taking a bit longer than it used to! :worried:
Dave G
QuoteLast time I went driving, gradients were on the signs as a percentage. So surely road sign gradients are more familiar
Probably an age thing, at 81 I knew where I was with 1:x and used it for many more years than %
QuoteNot sure I see a connection here. Decimalisation of numerical quantities has been going on for centuries,
We in UK had been using feet and inches and £sd and Fahrenheit for centuries, many other countries also used non decimal units, the EU more or less forced us to abandon our units, if we had adopted the Euro then we would have lost £sd, but as we did not go Euro why change to decimal, businesses made a lot of money out of that, customers were used to ten pence being less than 1/- so happily paid it not realising it was equal to 2/-, it took some time for us to wake up to reality by which time it was too late.
Quoteexplain why a non-decimal system be better than a metric system?
I didn't say one was better than the other, just that we had managed for centuries with our system, if it ain't broke don't fix it!
I must admit, as a comparative youngster (hey, at least I remember when King George VI shillings were still in circulation), and despite having spent most of my adult life in fully decimal countries, the "old" notation still feels more intuitive.
Quote from: Dorsetmike on April 24, 2015, 04:15:51 PM
Quoteexplain why a non-decimal system be better than a metric system?
I didn't say one was better than the other, just that we had managed for centuries with our system, if it ain't broke don't fix it!
Non-decimal systems actually work better for mental arithmetic, especially dividing, for example into thirds. You can divide one shilling into three lots of 4 pennies, but trying the same thing with one pound and you always get something left over. "Old money" had lots of fractions built in: farthings (1/4 penny) and ha'pennies (1/2 penny) within a penny; thruppence and sixpence were quarters and halves of a shilling; a crown (5 shillings) was a quarter of a pound, and various others. Such a system was very flexible with lots of options for dividing up a sum of money in a neat way that didn't leave odd bits leftover. So yes, non-decimal systems actually can be better for money systems before calculators and computers.
In fact fractions are generally better than decimals when it comes to precision. If I say 1/3rd of something, that's precise and you know exactly what I mean. But if I do that in decimals, at best you'll get an approximation, 0.333 or something like that. Not the exact, precise number because you can't write down a third in decimals without using an infinite number of digits!
But oddly enough decimals are much better at informing you about how precise a measurement is. If you measure things in fractions, usually you end up approximating to some degree, depending on what you judge a sensible about of precision for the situation. So I might measure a bit of wood and say it measures 6 and three-sixteenths of an inch. But how precise were you in actual fact? Did you read off to the nearest line on your ruler? Was the wood actually somewhere between two lines on the ruler? With decimals I can say 6.2, or 6.19, or 6.188, or 6.1875 or whatever... and it's clear what my level of precision was (even better if I say 1 dp, 2 dp, 3 dp or 4 dp in this case). So in science and engineering, decimals are better.
I find all of this fascinating, especially when you reflect on how routinely we mix base-10 (decimal currency) with base-12 (such as feet/inches) and base-60 (time, angles and coordinates on the globe). Nobody fusses about the base-60 because it's actually a lot better than trying to do base-10 for that sort of thing. 60 is divisible in lots of ways (1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60) so you hardly ever need to use fractions in most day to day situations. But mention the idea of base-60 without reminding them about time, angles or coordinates and people freak out!
Cheers, NeMo
I think better in metric these days. Especially as 1km = 10 minutes walk.
Quote from: Bealman on April 24, 2015, 12:23:08 PM
[smg id=24347 type=preview align=center width=400]
:D :thumbsup: :beers:
Brilliant !
(pun intended ;) )
:thumbsup: Nice one !
Quote from: deibid on April 24, 2015, 02:53:20 PM
A % number is not decimal nor imperial.... is a proportion, by definition it does not mean any "unit"... 5% means anything you want it to mean, five inch each 100 inches or 5 cm each 100 cm... the choice of units is yours.
Regarding railway signals... modern HS lines in Spain express gradients in %
It is a proportion and dimensionless but it can still have (dimensionless) units, so not always units of your choice.
Gosh !
Just a minute folks, ( pun also intended), if we are to deviate without a pause but perhaps some repetition into monetary metrics then try also :
Metric tensors and Reimann manifolds,
oh no, perhaps not else we will be back to motor cars/bikes !! :)
I suppose it is all relative Albert.
Wot, no opinions on stall currents ?
Quote from: NeMo on April 24, 2015, 05:43:43 PMand base-60 (time, angles and coordinates on the globe). Nobody fusses about the base-60 because it's actually a lot better than trying to do base-10 for that sort of thing. 60 is divisible in lots of ways (1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60) so you hardly ever need to use fractions in most day to day situations. But mention the idea of base-60 without reminding them about time,
:thumbsup: :laughabovepost:
60 - Oh gosh, any minute (duh) now we'll be debating if it was a good idea to get rid of Babylonian hours ( and Italian for that matter), which we were all used to in days of yore, from of off sundials :laugh3: :heart2:
Edit:
PS It is said, or supposed, or our only evidence (in cuniform clay), is that the Babylonians first ( were the first ?) used base-60 for trade / business because of (as NeMo says) its convenient divisibility from quantity.
One of the challeges of this computerised, GPS world is that the base-60 concept is gradually being perverted. GPS systems can read out (IIRC) in degrees-minutes-seconds (and decimal seconds!), degrees-minutes-decimal minutes, and even degrees-decimal degrees. Usually it's a user choice, but sometimes that choice is so buried in the depths of the user configuration menus one can be unaware of the meaning of the results being reported on the little screen. When you superimpose that onto people who don't understand that a minute of longitude is not the same length as a minute of latitude, all chaos can break loose.
I grew up in the UK learning long division and multiplication in bases 112, 14 and 16 (hundredweight, stones, pounds, ounces) and 20 and 12 (currency). Then the science classes changed to metric (actually SI) and the engineering degree was done in SI as well. Out of college I joined a firm working in the oil industry and suddenly everything was in traditional (american) units (aargh, what's a kip? :confused1:). Before I retired, I headed up engineering for a major multi-national company and was continually challenged with (otherwise excellent) American engineers who had no clue how to work in "metric" units and were too proud to call their european colleagues to find out what units were normally in use (at best they'd call the UK or Ireland and end up being led astray when it came to mainland european usage) >:(. Getting anyone to understand the significance between an "m" prefix and an "M" prefix was a lost cause. :veryangry:
Quote from: Jon898 on April 24, 2015, 09:08:18 PM
American engineers who had no clue how to work in "metric" units
It is said ( but I have not read the originals ) that some of them did try, but lost a Mars mission as a consequence.
You're spot on: http://www.cnn.com/TECH/space/9909/30/mars.metric.02/ (http://www.cnn.com/TECH/space/9909/30/mars.metric.02/)
On a recent train journey in Sri Lanka (I posted a few pictures earlier) I was talking to the driver, and he referred to distances along the track in "chains". I vaguely remember mention of chains in my school days, so refreshed my memory with wiki...
Quote: A chain is a unit of length. It measures 66 feet, or 22 yards, or 100 links,[1] or 4 rods (20.1168 m). There are 10 chains in a furlong, and 80 chains in one statute mile. An acre is the area of 10 square chains (that is, an area of one chain by one furlong). The chain has been used for several centuries in Britain and in some other countries influenced by British practice. Unquote.
So then I recalled "perch" as a measure of area - wiki again:
Quote: As a unit of area, a square perch (the perch being standardized to equal 161⁄2 feet, or 51⁄2 yards) is equal to a square rod, 30 1⁄4 square yards (25.29 square metres) or 0.00625 acres, or 1/160 acre. There are 40 square perches to a rood (A rectangular area with edges of one furlong (10 chains i.e. 40 rods) and one rod respectively), and 160 square perches to an acre (an area one furlong by one chain (i.e. 4 rods)). This unit is usually referred to as a perch or pole even though square perch and square pole were the more precise terms. Confusingly, rod was used as a unit of area but it meant a rood. Unquote.
Now I remember why I liked it when metric came along. Oh! and pocket calculators saved my life from slide rules and log tables.
Tom.
Talking of calculators or was it gradients.........I bought my first pocket calculator in Dixons in about 1974 for 15 (post-decimalisation) quid. The LED display was red, and it did lots of clever things like add, subtract, divide, and multiply. No memory function though.
But even after 41 years I still like doing mental and pen powered arithmetic. Sitting in the sun a couple of days back i had a lot of enjoyment mapping out a track layout using Peco Setrack dimensions, and knowing the tangent of 22.5 degrees. A combination of sunglasses and an LCD calculator screen was not much use.
Quote from: woodbury22uk on April 25, 2015, 10:17:56 AM
Talking of calculators or was it gradients.....
:laughabovepost:
Well originally I had hoped it would be about how to measure the performance of our locos with a
British Standard NGF standard repeatable method rather than anecdotal tales of "mine will pull X hundred dapol "
But, great fun / read it has all been thank you everyone , it now seems that we have become totally derailed and that pull is not on the agenda.
I'll leave Webbo to try again perhaps :)
Meanwhile maybe a mod. should move this to General Chat ?
I'm inclined to think that now this topic has gone down the slippery slope, it could be an uphill struggle to bring it back. :sorrysign:
I pefer to see a gradient (road or rail) as 'x in y' rather than percent. It just brings a better visual image, (for me), but I guess it's because that is what I grew up with.
Since all of these measures still reside in land surveying, why do I think that somewhere gradients used to be measured in rods per mile? Of course two chains per mile (8 rods per mile) is actually a reasonable limit to strive for in our models ::).
General rule of thumb - if you can fit it on your layout, it's too steep. ;)
Metrication was the spawn of the devil, or even worse foreigners.
I can visualise a yard, i know the length of the cricket pitch is a chain and can see that In my mind, and my car travels in miles per gallon
When we go shopping I know what a 4lb chicken is or a pound of cheese. Even a quarter of sweets for the kids makes sense.
A steep hill is 1 in 3 and always will be.
It's about the only sensible thing the Americans do is shun the use of metrics, although I think few weaklings are starting to give in.
If your layout is running steam, then these made up metric things hadn't even been invented when they were in use.. :no:
Quote from: Greybags on April 25, 2015, 09:56:27 PM
Metrication was the spawn of the devil, or even worse foreigners.
I can visualise a yard, i know the length of the cricket pitch is a chain and can see that In my mind, and my car travels in miles per gallon
When we go shopping I know what a 4lb chicken is or a pound of cheese. Even a quarter of sweets for the kids makes sense.
A steep hill is 1 in 3 and always will be.
It's about the only sensible thing the Americans do is shun the use of metrics, although I think few weaklings are starting to give in.
If your layout is running steam, then these made up metric things hadn't even been invented when they were in use.. :no:
And things really started to go wrong when we started to use paper instead of slates and styluses - oh please! Things are always changing and moving on aren't they. :D
Good grief!!!
I think I have lost the will to live !!!
Lost the thread on this thead a while back, turning into gibberish.
Quote from: austinbob on April 25, 2015, 10:12:10 PM
And things really started to go wrong when we started to use paper instead of slates and styluses - oh please! Things are always changing and moving on aren't they. :D
Yes they are, but that doesn't necessarily mean they are better, just different.
And to return to the topic, it is far easier to measure a 1 in 33 gradient, as it is a ratio, not a percentage.. Measure 33 along, and it rises by 1, be it inches, mm, chains or yards.
I was just trying to show that it is often easier to visualise the older imperial way of doing things that it the more "modern" way, as we have reference points built in to our culture .. i.e. the cricket pitch.. The majority have seen a pitch and can see it in their minds, so they can relate something as being "x" number of pitches long or "x" times 22 yrds.
Take it to the pub, we all know what a pint looks like, but how many can see something and say its a litre..
As I have said, it was just supposed to be a slightly humorous (failed) way of showing that the older ways can sometime be easier to understand, in this case gradients.
I repeat. Good grief!!!
Quote from: Webbo on April 26, 2015, 10:39:55 AM
I repeat. Good grief!!!
I think I might be
'inclined' to move on from this thread.
:)
Sloping off myself now.
Quote from: Greybags on April 26, 2015, 09:18:12 AM
Take it to the pub, we all know what a pint looks like, but how many can see something and say its a litre..
To you. But youngsters are just fine with both, and use litres in school. That in turn means they can work more easily internationally. Even the US link is often tenuous: Americans use a different gallon entirely, and Americans sell milk in quarts, not pints.
Quote from: Greybags on April 26, 2015, 09:18:12 AM
As I have said, it was just supposed to be a slightly humorous (failed) way of showing that the older ways can sometime be easier to understand...
To you.
Let me give a parallel: I use a Mac, and have done for over 20 years. But at work I have to use a Windows PC. To me, Windows seems ugly, clumsy and stupid. But if I'm being objective, that's because I'm less familiar with it. To someone who has used DOS and Windows for 20 years, I dare say Macs look just as alien and obtuse.
Cheers, NeMo
I think this topic has been going off track for a while and I think that the original question has been answered.
So i am locking :locked: the topic for now and will see how easy it is to split out the discussions on measurement systems into another topic for general discussion. :)