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The real issue is the slope of the grade. If you are forced into a steep grade, start and stop your grade very gently, say start with a half or 1 percent slope, then transition the grade as you go.

Take your longest engine and car and verify the train does not bottom out where the grade stops and starts. I use two Atlas 21" Budd cars. They are VERY unforgiving.

Avoid any grades that stop or start on a curve if you can.

 

 

I'm sure I'll be able to figure this out when I get there, but I have to ask a newbie-ish question that's related to this thread.  I'm asking because, with the exception of a 110 Trestle set on the carpet, I've never been one to build grades on a layout.

We will be building a modest grade on a tubular track layout we are building.  The grade will really just be a slight rise along an 8' section of straight track.  So, in other words, 4' up to the peak, and then 4' down.  The grade that we will be building will run along the surface of a suspension bridge so that's the overall rise/fall to keep in mind.  I'm just going to go with what looks right, but I can't imagine a rise and fall of more than 2-3".

My questions are as follows:

  • The answers about how to start off the graded section are being answered on this thread, so I think we're ok there.

  • Is it better to use many 10" (or shorter) sections of track to facilitate the flexibility of the rise, crest, and fall?  Or are using 40" straights better?

  • These questions/answers above talk about the start of the grade, but I'm equally concerned about the crest.  How do people handle that, or even just the are where the grade starts downward?  Obviously, this is the inverse of handling the start of the grade, but I'm wondering if there are any special issues to consider.  Obviously, I want to avoid a situation where the pilot truck of a steamer (or even a GG1) flops out of place right as the loco reaches the crest.


Any thoughts, tips, to-do's, or even war stories would be most welcome.

Thanks.

Steven J. Serenska

 

 

If you keep the grade at 2% or less you will have no problems with starting and stopping the grade. So, that means 100 inches to rise 2 inches. To clear the track below I would use no less than 5.5 inches from the lower rail to the upper roadbed. This means 275 inches to reach 5.5 inches of clearance. It not only works right but it looks right. With a 2% grade or less you can continue the grade on curves without difficulty. I use Gargraves Phantom Rail and it works beautifully . It is used with cork roadbed from Midwest. The sub roadbed is 1/2 inch a-c plywood. I strongly recommend so called open grid construction as described by Linn Wescott in his classic book on model railroad benchwork which you can easily find on Amazon. My layout is 30 years old and I have never had to revise a grade because of problems with derailing or engines failing to climb the grades. Good luck and start with Linn Wescott's great book.

"We will be building a modest grade on a tubular track layout we are building.  The grade will really just be a slight rise along an 8' section of straight track.  So, in other words, 4' up to the peak, and then 4' down."

I am thinking you mean 4 inches up and and 4 inches down? not 4' or 4 foot?

So rise/run X 100 percent is your slope.

your run is then 1/2 the 8ft...

so 4/96 x 100= 4.2 percent slope which is quite aggressive with no room for a flat at the top of the grade.

Can you lengthen the run of 8 ft?

Last edited by J Daddy

I've done tests with grades up to 10% and currently have a long stretch of 8% grade that starts with an O40 single-turn helix. Grades of 4% to 6% are not unreasonable for most three-rail trains if you have moderate-length trains and powerful locomotives. Steep grades can have reliable operation if you avoid kinks and twists in the track. Steep grades allow more possibilities in track planning for limited space.

For the newbie people who have so many questions about how to build grades: may I suggest that you build some temporary trial layouts and you can see what works and what doesn't work with your own equipment, before you attempt to build a "permanent" layout.

100_3518100_35552012-2131-trial layout O27

Last pic shows a small trial layout to test feasibility of Lionel-type 5.6% grade. The main issue here was uphill-and-downhill speed control of typical postwar loco with spur gears. If vertical curves in the track cause derailments, just shim them to even it out.

Attachments

Images (3)
  • 100_3518
  • 100_3555
  • 2012-2131-trial layout O27
Last edited by Ace

I find using longer sections of track in the center of the grade allows you more flexibility where you place your supports.  Using shorter pieces at the grade transitions can make it easier to fit in a smaller space.  As noted above, test with temporary setups and use your longest engine and rolling stock.  Also test with any rolling stock that has lower clearances like heavy duty depressed flat cars, Schnabel cars, or similar.  My last test is always a longer consist to see if any cars bind or come uncoupled (different mfgs. can have slight variances on coupler height).  Yes, I have had 2/3 of my consist suddenly roll back down the grade with neither coupler open.

Good luck!

J Daddy posted:

"We will be building a modest grade on a tubular track layout we are building.  The grade will really just be a slight rise along an 8' section of straight track.  So, in other words, 4' up to the peak, and then 4' down."

I am thinking you mean 4 inches up and and 4 inches down? not 4' or 4 foot?

So rise/run X 100 percent is your slope.

your run is then 1/2 the 8ft...

so 4/96 x 100= 4.2 percent slope which is quite aggressive with no room for a flat at the top of the grade.

Can you lengthen the run of 8 ft?

I'm not sure what type of grade Pat will be doing.  If he would give us some additional info on what he is planning  (length of climb and how high)  would help.

It looks like Stephen is just going to go up for four feet (maybe to a bridge crossing a river, or just for scenic effect?), then back down. It doesn't look like he is going over another track.  If he uses a 2 percent grade, his track will rise only 1", 3 percent 1.5" and 4 percent 2". 

I've used the same technic at both the start of the climb and at the crest.  That is using a 4" wide piece of plywood at the transition areas.  Make sure the first foot of the plywood is firmly attached to the surface, then bend it to the grade you want and support it with risers.  The plywood will make a nice curve from flat to grade/grade to flat.  I then secure a Gargraves 37" section across the bend so it forms a smooth curve.  Don't use sectional track.

If Stephen plans to keep the grade at 2 percent, I would go with Dale's suggestion to use Woodland Scenics Styrofoam risers, again using a 37" straight section to make a smooth transition.

Another factor is coupler shaft length. A longer reach means more drop or rise at the knuckle during grade transitions. Ease into them even if your grade maximum is steeper.

I have a longer transition at the crest where the load while climbing is higher from cars entering the grade. It gives more uniform traction opportunity on the climb.

Ron:

Thanks very much for these thoughts.  I was going to head in the direction you describe, but it's somehow quite helpful to see it all written down by someone else.

Yes, this particular rise won't cause one track to rise over another.  We only need to have enough of rise/fall to simulate the subtle arch of a suspension bridge.  Something like:

The plan is that, if we find the grade to be too steep for the available length, we will do a "fake out" effect of making the side girders more steeply arched than the actual roadbed.

This bridge is 1-2 miles from our home, btw.  The span that you see in the photo will be about 8 feet on the layout.

Steven J. Serenska

 

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