How do you start a grade?

[cudaken]

 Simple question I just don't want to make a miss stake. I am plainning to use 1/2 thick plywood to run 2 lines on. It will be added to a flat section to start a 1.5 grade throught the current hill project. I am guess 4" should handel 2 main lines with no rubbing of trains.

 I know that the 1/2 thick plywood jump will be a problem and the plywood will need to be tappered, just how much, say 6" back, 12" or 36". All so how many feet or inches should I places supports to keep the plywood from flexing?

                            Cuda Ken

[stokesda]

Ken,

You need to ease into the 1.5% grade using a transition that goes from 0% to the beginning of the steady 1.5% grade. The slope of the transition should steadily increase from 0 - 1.5% along the length of the transition. Just doing some quick trigonometry, it looks like your transition section for a 1/2" thick piece of plywood would have to be, at a minimum, about 33 inches (!). Anything shorter, and you will have a short section of grade greater than 1.5% between the flat surface and your final grade of 1.5%.

Having said all that, there are a few ways you can get the transition going:

1. Use a piece of scrap foam or something sloped properly to add in front of the edge of the plywood.

2. Use a jigsaw to cut out the approach to the 1/2 inch plywood, as you'd do with a "cookie cutter" layout pattern to get the "up and over" sections. Then use something to pry up the end of the approach section to match the same level as the 1/2 inch plywood.

[bogp40]

Ken,

You need to ease into the 1.5% grade using a transition that goes from 0% to the beginning of the steady 1.5% grade. The slope of the transition should steadily increase from 0 - 1.5% along the length of the transition. Just doing some quick trigonometry, it looks like your transition section for a 1/2" thick piece of plywood would have to be, at a minimum, about 33 inches (!). Anything shorter, and you will have a short section of grade greater than 1.5% between the flat surface and your final grade of 1.5%.

Having said all that, there are a few ways you can get the transition going:

1. Use a piece of scrap foam or something sloped properly to add in front of the edge of the plywood.

2. Use a jigsaw to cut out the approach to the 1/2 inch plywood, as you'd do with a "cookie cutter" layout pattern to get the "up and over" sections. Then use something to pry up the end of the approach section to match the same level as the 1/2 inch plywood.

Dan gives some good advice. The method you need would depend more on your type of construction. On foam based layouts most tend to prefer foam risers. Shims and/or spackle can smooth the upeasing for the grade.

If your base is plywood, the cookie cutter approach gives you the gentle easing needed. If you have to, carry the plywood subroadbed futher back into the level to attach solidly to 2 flat joists. Bend up for the grade and add the risers needed for the 1/1/2%. This gives you a very stable and flat foundation for the track. Shims can be added or adjust the riser to control the grade if needed. The plywood works the best for this when the outer ply grain follows the track. The 1/2" ply will bend better w/ outer graining @ 90 degrees to the track, but it will not be as strong and depending on the grade of ply, may not keep it's position and can wave or distort. Even when you cut the radiuses in the 1/2 ply, you shouldn't really let the outer grain exceed anything more than 45 degrees to the track. If your unsure about the stability of the jointed sections of the ply subroadbed, scab  a piece of ply glued under the jont. You can still add a riser under this laminated section.  One hint on the risers, don't bury any DW screws under the roadbed. Any adjustments or future work means pulling the track or cutting the screw under the ply (a real mess).

[selector]

Ken, you can get thin wooden shims from your hardware store where they sell supplies for doors and their installation.  Theses shims are used in wedging door jambs.

Glue a couple of them at the base of your cookie cutter incline, abutted to its base.  When the glue is set, use a belt sander and fashion a very shallow curve out of it all.  Won't take you long, and your flextrack will naturally make its own transition when you place it atop this area.  Shim any weakly supported or low spots under the ties with small tabs of cardstock.

Then, test it before you ballast or glue.  Run all your engines both ways across this, reversing and forward, under normal trains loads.

-Crandell

[bogp40]

Ken, you can get thin wooden shims from your hardware store where they sell supplies for doors and their installation.  Theses shims are used in wedging door jambs.

Glue a couple of them at the base of your cookie cutter incline, abutted to its base.  When the glue is set, use a belt sander and fashion a very shallow curve out of it all.  Won't take you long, and your flextrack will naturally make its own transition when you place it atop this area.  Shim any weakly supported or low spots under the ties with small tabs of cardstock.

Then, test it before you ballast or glue.  Run all your engines both ways across this, reversing and forward, under normal trains loads.

-Crandell

As Crandall says: TEST, TEST, TEST.....

The most affected pieces of equipment on poor or too sharp an upeasing or overeasing is found on longer engines and/ or rolling stock. A swicther or geep coupled to a 70ft plus car especially w/ extended coupler boxes will have the greatest vertical movement and chance to uncouple.

These are the spots where some using shelf couplers try to eliminate unwanted couplings. Some real bad transitions and shelf couplers can actually lift a truck causing a possible derailment.

If you use a wood shim, try siding shingles. A white cedar is usually 16", red cedar 18" on the taper from 3/8" to feathered/ 1/16". Before ballasting, make sure they're glued down well. Sanding or future ballasting can cause them to curl at the edges. 

[cudaken]

 What is a cookie cutter? I have readed this tearm but not sure what it means. Yes the bench is plywood.

 I have picked up a few ideas but not sure what I am thinking is what you kind folks are telling me. Anyone have any PIC they could post?

 Here in the nut shell is what I am trying to do.

 

 I want to start the grade heading into this tunnel, it is a lift off so I can work there. I want to be able to do as much as the grade work I can with the new plywood section off the main bench. Lay rails and cork bed, then install. Reason is I have very little time to spare and both the A&B line runs throught the hill. I hate to have no train time.

 If I start inside the hill it would mean a little steeper grade 2.08 but I can open the garage door to do the work, if before the tunnel I will be laying on the 4 foot wide bench. Reason I am wanting to do this is for the new section of bench work that I will be adding.

 

 The section that shows extra bench added will be a tressel and I want a little head start on the grade. It will all so help where the two lines cross over each other. New section is a open grid and has 4 sections that will be bolted together.

 The four sections are bulit and waiting to be hooked to each other. Out side edges will have plywood about 6" wide then 2 to 4 inchs of foam. Not sure how deep I want to go yet. s far as the hidden stagging, there will be less than shown but there will be suffcent room for around say 50 cars. 

 New section will be a mining company and is 8' X 5' and will be free standing.

 I wish I could take credit for the plan but a great member here took a ruff idea and refined it.

 Wife says we have cookie cutters for Star, Christmas Trees and Candy Canes but nothing for a grade.

 

[dehusman]

 What is a cookie cutter? I have readed this tearm but not sure what it means. Yes the bench is plywood.

Cookie cutter is putting the plywood just under where the tracks are.  Imagine if you traced the track centerline for the track going up the grade.  Then draw a line an inch or inch and a half from the center line on both sides of the center line.  Then imagine cutting along those edge lines.  Then you just bend the plywood up to start the grade.

Buy a book on building benchwork to see illustrations.

Dave H.

 

[selector]

I hope I don't end up in the caca for doing this, but this came up first on my search, and it belongs to another forum.  The first photo tells it all.

 

http://www.the-gauge.com/showthread.php?p=180082

[tgindy]

What is a cookie cutter? I have readed this tearm but not sure what it means. Yes the bench is plywood.

Here is a quick example of cookie-cutter...

If you would trace a simple figure-8 on a piece pf plywood, then scribe the width of the roadbed, you then begin cutting out the roadbed without detaching the cut-out roadbed  from the plywood.

In theory, 50% of the figure-8 will be "cookie-cuttered."

You then raise the middle of the overpass section with two supports to an adequate height for train clearance.  Once you are satisfied with the grade & clearance you can permanently attach supports at intervals along both sides of the grades up to the overpass.

When everything is secure and bolted down, you can cut out the overpass top to place your warren truss bridge.

Now you have the equivalent of all of those plastic piers in that Christmas train set.

The start of the grade automatically grades into that 50% of your layout that is already flat, and; the beginning of your grades on both sides (or ends) of the figure-8 is totally secure because it has always been (and still is) attached to the original plywood base.

For what it's worth, I have seen forum comments by published MRR auther(s) who use the cookie-cutter method when it is the most efficient method to achieve their goals of a gradual grade.  The tension of just raising the center of the roadbed you have just cut out generally gives you the grade you are looking for anyhow, and it is totally secure.

"Cookie-cuttering" is actually a form of "it's good enough" that you see described so much in model railroading articles.

[R. T. POTEET]

 Simple question I just don't want to make a miss stake. I am plainning to use 1/2 thick plywood to run 2 lines on. It will be added to a flat section to start a 1.5 grade throught the current hill project. I am guess 4" should handel 2 main lines with no rubbing of trains.

 I know that the 1/2 thick plywood jump will be a problem and the plywood will need to be tappered, just how much, say 6" back, 12" or 36". All so how many feet or inches should I places supports to keep the plywood from flexing?

                            Cuda Ken

Some folks would find my layouts boring but space limitations over the course of the last 20 years or so forced me to model a flatland railroad.  There was one situation on my last HO-Scale pike before bolting to N-Scale in the early '80s where I needed to bring an industrial sidetrack up a 2% grade in order to climb the required (prototype) 26 feet to clear the mainline.  I layed out the tangent on the grade and I layed out the tangent on the flat and I cut a length of ½ inch ply to bridge the space in between where I wanted the foot of grade to be.  Then I weighted that piece into the transition position with a cinder block.  Believe me, Ken; there is considerably more flexibility in ½ inch ply than there is in a stick of spaghetti.