I am planning my fist garden railway and want to know how i calcualte grade. 4% grade means what? is that 4" of rise over 100" of length. thanks for the help
Yes, that's right. Try to limit yourself to a 2-3% grade. I round off the 100 inches to 8 feet then all you need is an 8 foot 2x4, a level and a tape measure to figure out your grade.
- Brian
CCRAIL
A few "general rules of thumb".
Grades: Try your best to keep the grades below 4% (try harder for 2%). Higher grades mean fewer cars being able to be pulled by any given engine. Higher grades also cause more wear and tear on engines and drive trains, leading to stripped gears.
Curves: Keep your Curves as large as possible 8-10 ft diameter when possible. Tighter curves also limit pulling power, (actually the cars will begin to tip over into the curve is the train is too long. 8 ft. curves will allow you to run most everything out there on the market, with maximum train length. 4~6 ft curves will limit what equipment you will be able to run.
Tunnels: Keep them straight and no longer than you can reach from each end. If you do make them longer, ensure you install access portals.
Rails: Longer rails (5, 8, or 10 ft) make for fewer joints, which makes for better operations. In other words, fewer "picked joints" causing derailments.
Now that I have recited the general rules, as we all know every rule is designed to be broken. You need to know the consequences before violating the rules. I have broken them all.
Grades: I have a "ramp section" for trolley service to the top of my waterfall. Due to constraints as to how much real estate was available and the height I needed to climb I have a 38 foot long section with a 14%~16% grade. I did this knowing I would be replacing gears/street cars a lot more often than should be normal. The only things running on this section are "expendable" streetcars.
Curves: All my mainline curves are 8 ft. Selected locations have a curvature of 6 ft and one location with a 4-ft radius, at the beginning of the streetcar line to the top of the waterfall. Being aware of these limitations, I can still have fun operation.
Tunnels: Mine makes a 90-degree curve, but is still less than reaching distance. This was a concession to the requirement to give the wife her Koi pond at the same time and location as my GRR.
Rails: All my mainline rails are 5-ft sections soldered into 10-ft sections. Like I said above, fewer joints present fewer opportunities of derailments.
Tom Trigg
You're right, 4" rise in 100" of travel is a 4% grade.
The formula is R/L=% ...... R=rise, L=length of travel, %=percent of the grade .
So, in your case, 4"rise/100"of length=.04 (.04x100=4%).
Walt
One more thing Keep your track level side to side. twisted track will cause derailments.
dave
The head is gray, hands don't work , back is weak, legs give out, eyes are gone, money go's and my wife still love's Me.
dwbeckett One more thing Keep your track level side to side. twisted track will cause derailments. dave
I second that motion! A little bit of side to side sway looks realistic for an old dilapidated branch line. If you want the sway then try to stay around 1/32 ~ 1/16 inch difference in rail level. Depending upon your car length and weight anything more than that can cause cars to tip at speed and on curves.
and then..... 1/8 inch per foot equels 1% so if you only have a 2 foot level and have the need for 3% grade use a scrape of 1X4 ( 3/4" ) at one end of the level with the other end on the same serface to get your desired grade.
Dave
P.s. I'm Currently using 3/8" spacer in 3ft for 1% grade.................
steamdonkey:
Most execelent comment, must add that one to the standard "guidelines" listing.
This is my first time building a GR and it is a small start. The layout is about 40 foot total mainline with a switch yard but I am worried about hurting the gears on my engine as I have a section that is about 40 inches long and 3 1/2 inches rise meaning about 8% grade. I run a USA trains GP38-2 with about 5 smaller cars so it goes just fine and I am hoping it wont do to much damage. Any advise on the damage I might be doing to the engine would be great.
Thanks
That's a pretty steep climb and the USAT 2 axle diesel trucks are notorious for splitting the gear hub on the drive axles under a heavy load. Many fix it by wrapping the split hub with thread soaked with CA or replacement gears are readily available.
-Brian
Where would be the cheapest place to get a replacement and it should not be too bad as it only pulls two boxcars, two little flatcars, and a small tanker right now. I am looking at landscaping it too about a 3% grade.
Regrading sounds like a good idea. The GP38 should be able to handle ~8 cars on a 3% grade.
Order replacement gears directly from Charlie Ro. Contact customer service (best by phone) for ordering info - http://www.charlesro.com/contact_us.htm
Use the short level across the rails for side-to-side measure, and use the long level along the rail length to check for humps or dips. Fix everything by pouring on additional ballast, gently lifting the track and and working in gently with the brush. If you have a hump, try gently working the track (use a little pressure and gently side-to-side motion) down into the ballast first, or if that isn't enough. then remove excess ballast until everything is level. Keep measuring across the rails with the short level to avoid creating more problems as you perform your repairs.
Also, it has not been mentioned above that we should avoid short transitions from level track to graded track and vice versa. Make the transition at the bottom and top of every grade as long/gradual as possible. That will help avoid de-coupling and derailment problems. Al
AL
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