I have a problem that I hope some one can help me with. I bought a gauge from micro-mart several months ago to help me keep my grades even. The only problem is that it is in 1 degree increments. So how would I figure a 1.5 or 2% grade in degrees. Also would the reading be the same, say at the bottom of the grade or middle or top of the grade or would the degrees be different. I trying to get a smooth grade throughout. Thanks in advance for any help you may give me on this.
A grade should have easements just like a curve. If your train is going along at a 0 grade and hits a 2% grade it would be like hitting a speed bump. So a grade change needs an easement at the start and end of the grade to make the transition from one to the other without the bump.
As for the gauge thing you have, a 1% grade is 1 inch of rise over 100 inch of travel. 2% is 2 inches of rise over 100 inches of travel. You could set a level on the floor finding a level spot then add 1/2 inch block under the end and measure off 50 inches. Most levels are 48 inches long so that will get you close. Then set your gauge on the level and see what it reads.
A half inch rise over 50 inches is a 1% grade. (1/2 inch + 1/2 inch = 1 inch), (50 inches + 50 inches = 100 inches). 1 inch of rise over 100 inches of travel = 1% grade.
EDIT: Also a 1/8 inch rise over 12 inches of travel is also a 1% rise. Most people have a 12 inch ruler in the house so by my thinking. Use a torpedo level and a 12 inch ruler with a 1/8 inch piece of whatever under one end to keep the grade going up the hill. If you keep the bubble in the center of the level the grade will be 1% for that 12 inch section of roadbed.
I suggest you get an electronic level. I have an 8-inch Craftsman model from Sears for around $20. It measures angles by percentages in tenths, or is that thousandths? (like 1.2% and 2.6%) as well as other ways (like inches per foot) .
Do you mean that it’s measuring the angle instead of the slope (Rise over run)? Or do you mean that it’s measuring slope, but not in small enough increments?
Many of these devices have a switch that changes the measurement from angle to slope – but you’ve probably checked for that.
It’s been a long time since I had Trigonometry, but if your problem is converting angle to slope, I believe you can use a scientific calculator and take the tangent of the angle, then multiply that by 100 to get the slope. Someone who remembers Trig better should jump in, though.
If you don’t have a scientific calculator, you can refer to an on-line chart like this
But that assumes the issue is converting angle to slope.
Good luck.
Byron
Byron,
I believe you are right on!
Dante
Unfortunately, an inclinometer, which is what you have, is really not very useful for measuring model railroad grades. Here is the conversion from slope (rise/run) to decimal degrees (the formula given earlier is correct - degrees is arctan slope, slope is tan degrees):
1 % grade (1 inch rise in 100 inches travel is 0.57 degrees, approx - very hard to see on your instrument;
2% grade is approx twice that, 1.14 deg - also very hard to read on a degree scale;
Or going the other way,
1.0 degrees is a slope of approx 1.75 inches in 100 (rise/run);
2.0 degrees is a slope of approx 3.49 inches in 100.
Your instrument is probably made for measuring much larger angles of inclination - say 10 or 20 degrees, or maybe even up to 45 degrees or so.
The advice given in previous posts is good - use a level to measure slope directly - tape a cheater card, graduated in percent slope, to one end of your level.
Dick Chaffer
An even easier way if you don’t have instruments or math ability is to simply figure out how far you want to raise your rails over a certain distance. Then, let a wooden lath or a strip of 1.4" plywood or MDF set the grade for you over that distance. If you anchor it at each end, and have the middle third (at least) planar or on a fixed rate of climb/grade, the flimsy material will make your easement for you.
However, to be sure your overall climb and grade are appropriate for your needs and for your locomotives, you should calculate the mean grade by using the formula as if the material were a rigid ramp following a straight line. As you approach the maximum ability for your engine or engine combination, you should understand that the actual middle third, the planar non-eased portion, will be substantially steeper in order to allow for the lesser contribution imparted to the lifting effort on the part of the two easements at either end.
Or, said another way, keep your grades low…less than 2% if at all possible without really screwing up an otherwise nice track plan. I have 3% and will do my level darndest to not put my locomotives to such a test on any future layouts.
Crandell
Thanks to all who answered my question. I think maybe I need to look in micro-mart and get a grade insturment that will be a little easier. A math whiz I’m not. I do appreciate the help. It goes to prove the old adage, Model railroaders are by far the friendliest and the most helpful. Again thanks.
I use the more costly gauge: http://www.micromark.com/Miniature-Digital-Level,9409.html It works great! For me it was worth the cost, as it measures both degrees and grade percentage (%), Iuse it on my drill press as well as the layout.
I model in Ho so when I started my grade I started my last riser at 4 inches ant took my 4 ft level and worked back to zero with a 1/2 piece of plywood under the lower end. It took almost 30 feet to get my grade where I wanted it so now I can pull about 60 cars on the grade with 2 loco’s with no problems, hope this helps,good luck Jim.
I got my gauge from Harbor Freight for much less than Micro-Mart. It measures in both degrees and % of slope. I also use it to set up my power tools. Seems to work just fine, especially for Super-elevation on curves and more importantly insuring I don’t have negative super-elevation.
Kevin
So I guess here’s the next question - how would you model something extreme, like Pike’s Peak, which has 22% grades? I’d love to model some extreme spiral tunnels in a bedroom layout in N scale but everyone here wants to limit me to 1 - 3%. Any suggestions?
(I’m a single guy & can put a train anywhere I’d like in my apartment…)
I may be wrong but I don’t remember a RR on Pike’s Peak. Cars and such can go up a grade of 45% incline if they have the traction and horse power.
I would think if you want to have a RR that steap, you would have to use a cable or coge system.
You’d use a model of a cog locomotive (usually european protoypes) and special rack track.
http://www.scottpages.net/WallMountN.html
These usually don’t go through spiral tunnels in real life (at least not at those extreme grades), so you might be mixing some different ideas here.
Edit: Although now that I think of it, there are a couple of lines in Switzerland that have both spiral tunnels and cog sections. I don’t know whether the rack track is in the tunnels, though.
bigpianoguy
Let’s see - First you start with an engine (any engine will do) and then you add a pusher engine because on a 22% grade the first engine likely ain’t going nowhere. Then you need to add a second pusher engine because the first pusher engine is doing the same thing as the original engine…and then you need to add a third pusher engine… and so on and so on until you either run out of engines or start to see smoke from the booster station! Then you can try Bullfrog Snot (really - its a real traction enhancing product that really exists!). If that fails and you don’t have too much smoke from the motors you could then douse the whole affair liberally with fine sand (having dutifully removed the metal bits from the sand beforehand with a suitable magnet) and then glue your throttle on maximum! OH - by the way - the passengers have to walk up hill and carry the freight!
OK - sorry for going on. I couldn’t resist.[}:)]
If you are serious you might want to look at N scale Shays or Heislers with very short trains. Others can suggest a maximum grade but it won’t be 22%.
I did see a really neat small N scale layout at a train show in Ontario a long time ago. It consisted of a pair of helix like spirals with mountain scenery blocking some of the view of the track. It was about 3 feet tall. The entire layout rotated at about the same speed that the locomotives climbed the helix. In other words, the engines stayed on one side of the layout and climbed as the layout revolved. Clever use of the two tracks meant that one engine would disappear behind the scenes for longer than expected while another would appear unexpectedly. There must have been some way for the engines to return to the bottom unseen because the display operated continuously. The grades were quite steep so the engines only pulled a car or two. I hope my description makes sense. It was way cool! Not a lot of switching though.
Dave
krondor123
Sorry, I kind of hijacked your thread. Just couldn’t resist being a comedian when the 22% grade question came up.[:$]
Dave
OK, gotcha - no grades over 3% without an assistive device, like a cog/rack system, in which case, anything goes; next idea will be a train ‘elevator’ to bring small consists down from my ceiling train to table level to impress company…I’ll let you know…
Hijack away. I kinda like reading about the 22% grade. But seriously, I am gonna get a grade insturment from harbor freight that I understand. Again thanks for all the answers.