How do you accurately measure gradient on a curve?

[Anonymous]

To all my good mates that want to divide anything by nought i say phooey. This is digging in the dirt in your backyard mate, and when it is over 30 deg C a cool beer is more important.

I really think i am pretty right, i am convinced that over 1 m track and this metres position and shape changes every time i move on to another small section (276 mm) of track; if i drop 2 cm i have a 2% gradient and i also have about a 2.2deg gradient. Over 4m i have in fact dropped 8 cm, i have proved that now ith my water level. 

If anyone disagrees tell me what you think; or any test i can do to get a more realistic figure.

rgds ian

[tangerine-jack]

Oh Dan, never give up, enjoy the forum for what it is and have some fun. Gradient angles in the garden really don't matter - except in Australia!! I'm 55 years young, have trains in the garden, drink good beer 'til it flows out of my ears, enjoy spirited conversation with my mates, watch as much football as I can, but most of all, I always have fun. I do not doubt your maths, I think you are at college and do them all of the time, just let us old guys have our bit of fun, well this one anyway.

Truly have a festive cheers,

Kim

 

 

 

perhaps I should stick in the MRR forums for a bit then... or hang around here more to figure out how well G scale can take grades.... HO wouldn't do so great*... and curves make it worse... i think to the effect of .5% for "broad" curves.

 

 

*from both experience and  what I've read - they lose ~50% pulling capacity for each % of grade or so.  Dunno if this holds true with G (or if it really even matters because trains aren't 50-something cars long)

 

 

Yes, please hang around here.  I feel you have not only a lot to learn, but a lot to give as well.  WELCOME TO THE REAL WORLD OF MODEL RAILROADING!!!!!!!  Quick primer, HO trains are toys and are not real models.  Real trains run outside in the dirt, so do we.  Real trains get rained on, so do we.  There are no critical measurments, no critical scale (unless that is what you want to do), and some garden trains do pull 50-200 cars up and down grades with no problems, in the snow.

Trust me, once you taste Garden Scale, there is never going back to puny little gurlie man toy HO scale.  Buy a shovel, you'll be needing it.

[ttrigg]

Ian;
Sounds like you started a regular feast here.  I'm afraid I am using a far too simple method.  Took a piece of string, tied a knot in one end measured and tied knots every quarter meter for 3 meters. I'll bend the track and have it somewhat in place, put the string between the rails and clamp it to the inside rail with a "alligator paper clip", pull it tight against the inside rail and at each knot I know how much higher the "lift" will be depending on the grade I'm after.  No science, no calculator required here.  Each knot represents a quarter cm lift for each percentage of grade I want.  After reading some of these posts I'm beginning to think I'm not having enough fun!  That's all right, I'd rather play in the dirt than push calculator buttons.

[Anonymous]

Tom mate, i read your post several times and i like it but i can't quite see what you are getting out of what you did. I am even astute enough to work out that you did not use a metric measure at all but 40" and every 10' and a quarter of a cm is not actually that is it? its 1/10"

Jack once more we are in agreement.

Rgds ian

[tangerine-jack]

That brings up a very good point, Tom.  There are a million and one ways to do whatever it is that needs to be done in the garden.  No one way is right or wrong.  Whatever works for you is the right way.

 

Guys like Dan are probably getting a culture shock on this forum.  I've found that it works like this:

• 1. an idea or question is brought forward
• 2. discussion on its merits
• 3. alternate methods or ideas are discussed
• 4. Ian poo-poos the whole thing
• 5. The Australians begin drinking cold beer
• 6. The English begin drinking warm beer (because their refrigerators are made by Lucas Electric)
• 7. Capt Bob invests in something
• 8. I bring up a bunch of useless technicalities because I spent 25K on a college degree and I'm going to use it one way or another!
• 9. Everybody goes outside and plays with some trains
• 10. Repeat step 1 through 9

 

Nobody is under any obligation to pay the least bit of attention to what anybody else has to say, take what you can use and leave the rest.  I've learned a lot, adapted some ideas and moved in directions I would never have thought of myself.  This is in fact MUCH different than the HO forum.  I like it this way.  I spent many years being stressed over a job that requires 100% accuracy as the only acceptable standard, now I want to be a bit more casual.  Maybe it's good, maybe bad, I don't know, but I like the format the way it is.

[Anonymous]

Jack once more i agree with you but i must take you aside and have a man to man talk to you; what time is it there; i know what time it is here and you are up to late or up to early. Its nearly 1 pm here wed 13 th and i think you are 14 hours behind us, so add 10 hours and it is 10 pm last night, right?

IaPS i am knocking off for lunch now,

[NeO6874]

Oh Dan, never give up, enjoy the forum for what it is and have some fun. Gradient angles in the garden really don't matter - except in Australia!! I'm 55 years young, have trains in the garden, drink good beer 'til it flows out of my ears, enjoy spirited conversation with my mates, watch as much football as I can, but most of all, I always have fun. I do not doubt your maths, I think you are at college and do them all of the time, just let us old guys have our bit of fun, well this one anyway.

Truly have a festive cheers,

Kim

 

 

 

perhaps I should stick in the MRR forums for a bit then... or hang around here more to figure out how well G scale can take grades.... HO wouldn't do so great*... and curves make it worse... i think to the effect of .5% for "broad" curves.

 

 

*from both experience and  what I've read - they lose ~50% pulling capacity for each % of grade or so.  Dunno if this holds true with G (or if it really even matters because trains aren't 50-something cars long)

 

 

Yes, please hang around here.  I feel you have not only a lot to learn, but a lot to give as well.  WELCOME TO THE REAL WORLD OF MODEL RAILROADING!!!!!!!  Quick primer, HO trains are toys and are not real models.  Real trains run outside in the dirt, so do we.  Real trains get rained on, so do we.  There are no critical measurments, no critical scale (unless that is what you want to do), and some garden trains do pull 50-200 cars up and down grades with no problems, in the snow.

Trust me, once you taste Garden Scale, there is never going back to puny little gurlie man toy HO scale.  Buy a shovel, you'll be needing it.

 

well, now that we've covered those bases - HO is a necessity at the moment (college kid).

soon as I get a real income and a house I'll probably have a  garden RR... and then I'll just need a supplier of coal (seeing as REAL trains ran on coal.. diesel just isn't my cup of tea)..

[Anonymous]

soon as I get a real income and a house I'll probably have a  garden RR... and then I'll just need a supplier of coal (seeing as REAL trains ran on coal.. diesel just isn't my cup of tea)..

Here's something to get you started (or at least whet your appetite):

Gauge 1 Coal-Fired Live Steam

[Puckdropper]

Model Railroad scales aren't mutually exclusive, you know...  I've got HO, N, G (In that order because it can be pronounced.)

 

Anyway, about the grade math and stuff.  If you want to (cold rainy day?) check your method against the actual math, you can figure out how far off you are.

 

There is another way to do grade measurements, one that doesn't require a calculator... just a level and tape measure.  Place the level on the point you want to measure to, level it, and drop the tape from the other end of the level (making a right angle) and note the distance from the level and the distance to the ground from the tape measure.

 

(Sure, Puckdropper expects us to go through Geometry and Trigonometry to calculate the degree on the railroad and NOW he tells us an easier way.  -- If I had thought of it earlier, I would have told you earlier.) 

[Anonymous]

Puckdropper mate, i am confused are you taliking to yourself or are you arguing with yourself or even agreeing with what has been said previously?

Rgds Ian

[GearDrivenSteam]

Seems I remember someone covering the tape measure already. I can't remember who, though.

[Anonymous]

Everyone i think robert, but on a curve you must use a soft one to go around the bends,.

Doing a measurement of gradient on an "S" bend is also hard to do.

Ian

[kimbrit]

Hi Ian,

I can't remember if this has been said, probably has, to measure the distance of the curve multiply by Pi, 3.142 if memory serves me right. 8' diameter curve is 8x3.142=25.136' distance.

Cheers,

Kim

[GearDrivenSteam]

I was being sarcastic. I had already covered a soft tape measure in an earlier post that seems to have been ignored. From your comment, evidently you missed it too. Oh well. S curves are easy. Just scotch tape the tape measure to the track, or to the road bed. It works great. Most of yall are making this WAY too complex. I would have my grade up and RIGHT while some of yall are still playing with formulas and calculators. That's funny.

[Anonymous]

This is a big worry Robert, especially if you read it in conjunction with my golden palm problem, they are actually side by side and both part of a larger project to rework my area 1. This is being done to accomodate a new  larher project to do with an "L" i have put in linking area 3 and area 1.

I have to abandon the whole thing temporarily soon, as we are going down to Sydney (1000 km away) in a short while, to be with family and freinds for my 70 th birthday and Christmas. We have 4 children and 11 grandchildren down there.

Rgds Ian

[Anonymous]

Go out there with some card boad and cut away.

[GearDrivenSteam]

I'm still unclear on how large the tree is. I'm not familiar enough with metric measurements to know them right off the top of my head. I know a man who had a 150 plus year oak tree moved and it cost him like 1200 bucks. Sounds like a lot, but when you realize the scope of the project ,it was well worth it since the tree is still prospering today. The city was going to remove it free of charge because it was interfering with a major intersection. The owner opted the noble way out. This tree was more then 4 feet in diameter. He's got some pics. The nect time I'm over that way I'll try to get some and post them. It took one HELL of a BIG truck to lift that tree out of the hole. I had no idea a tree that size could be moved until he had it done. It was truely an amazing thing to see. After it was all said and done, the city actually paid half the bill since they saved the tree.

[spikejones52002]

You measure the circumference of the desired curve. Then you know how much elevation you need to get your desired %.

[Anonymous]

Phooey

Rgds Ian

[Anonymous]

I wish to do this over a distance say about a metre. The method i use is ok but pretty crude and not very accurate. I use a stepping block and a 1 metre long piece of wood and a spirit level. This is ok but it is just point to point and doesn't allow for the extra distance of the curve. 

Rgds ian 

 

Dear Ian,

 

Regards from our techie: 

To measure the grades in curves one could use a fixture as per attached.

 

The wheelsets are 500mm apart, the hinge base for the level measures 500mm. The grade is determined by measuring the gap between the wheelframe base and the free end of the hinge base.

One could use a metric ruler, a set of feeler gauges, a depth micrometer or joe blocks. Divide the amount by five and one has the precise grade of the straight. Since an accurate measurement is required, here are the factors by which to divide for given curves:

LGB R1 = 1.103462 

LGB R2 = 1.018714

LGB R3 = 1.007702

Keeping the wheelbase shorter than 1000mm makes it easier the construct and  results in measurements which are large enough to be accurate and small enough to use ordinary measuring instruments.

An even simpler method would be using an electronic digital level which reads directly to percentage. By the time one divides 1.7% by the radius factor the number will grow to four or more digits after the decimal point. For R1 that would be 1.5406058% 

Hope that helps, best regards

 

ER 

 

[Anonymous]

Phooey to you as well.

Rgds ian

[Capt Bob Johnson]

If the engine can pull the desired train up the grade without assistance, it's the correct grade.

If you need to add a helper engine, it's steep!

If you need 2 or more helpers, it's too steep!

Phooey!

[Anonymous]

Even so Bob mate, what has this got to do with measuring a percentage gradient? very little i think.

Rgds Ian

[Capt Bob Johnson]

Several methods to answer your query have appeared in this thread.  Some of which, though very viable, you have dismissed rather curtly!

That being the case, either my answer is the one you can grasp, or you have incorrectly stated your question.   So, What was it you really wanted to know???

[Rastun]

Bob,

In answer to your question 1 degree would be a 2.222...% grade.

 

Jack 

[Anonymous]

Jack i am not being disagreeable here and i don't need to be patronised by others; however in my rough backward way; i reckon their is 100 points in 100 % and 90 points in 90 degrees.

If something is going straight up it would be at 90 deg and 100 gradient?

So the surely a degree would be 1.1 of a percent or is this too simple?

Rgds ian

[Anonymous]

Several methods to answer your query have appeared in this thread.  Some of which, though very viable, you have dismissed rather curtly!

That being the case, either my answer is the one you can grasp, or you have incorrectly stated your question.   So, What was it you really wanted to know???

Bob,

Thank you for pointing that out and asking the question!  

Best regards

ER 

[Rastun]

Jack i am not being disagreeable here and i don't need to be patronised by others; however in my rough backward way; i reckon their is 100 points in 100 % and 90 points in 90 degrees.

If something is going straight up it would be at 90 deg and 100 gradient?

So the surely a degree would be 1.1 of a percent or is this too simple?

Rgds ian

Just a little to simple Ian,

A 45 deg slope is a 100% grade since that slope rises at the same rate of it's linear travel.

In other words if the train is traveling forward and it rises 10cm on a 10cm length of track that would be 100% grade. It's rise equals it's run length.

So 45/100 = .45 degrees = 1 % or 100/45 = 2.222...% = 1 degree. 

I would say that for climbing hills, cliffs or what ever as in hiking they start using the degree of the slope to describe the face than a percentage. With aircraft we use degrees for indications of climb or descent or amount of bank etc.

For your question Ian,

Since you know where the elevation starts and where the elevation ends and how much track it takes to go between them, you can mathmatically figure out what the grade is. Basically put both ends where they need to go and make sure the slope between them is equal. One way to do this would be with a spirit level and a block on a car. Set the level and the block on the car to be level at your calculated slope and roll the car along the track adjusting the track to make sure your bubble always stays level.

 Rgds Jack

[GearDrivenSteam]

Correct. It's easier for some people (like me) put into grammar school geometry terms. Think of it like this: A 100% grade would mean one inch rise in one inch. So, that would form a nice little right traingle. I'm just gonna have to agree to disagree with all you slide rule and technical geeks. I can do exactly the same thing, and probably quicker with just the few tools I mentioned before. Nuthin to it. Some folks just ain't happy unless they are complicatin things all up.

[Anonymous]

This is waaaay to much thinking and MATH.......Just use the biggest radius curves and "eye-ball" it......works everytime.

We don't need to follow NASA/Govt. Standards you know..... 

 

dan