Figuring inclines and parallels

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jacon12

Member
In my plan below, on the middle table, my track... starting at the 0 elevation point, climbs steadily to 3 3/4ths inches then levels off for the bridge over the lower track. It stays level across the bridge and then starts it's drop back down to a height of 3 inches..

figuring on the 'decline' stopping and going back into level right about where you see the red arrow or just past the turnout for the passing track, but just before the turnout for the siding. This is just about 5 feet from the bridge to that point and a 3/4 inch drop. I'm making the incline out of a single piece of 1 inch foam and I'm placing foam supports about every foot. The only way I can figure it is that if it's a 5 foot long run is to divide 5 into 3/4ths and I come up with less than 1/8th. Thats getting pretty hard to measure and accurately cut out of scrap foam for the intermediate supports. The logical way to do it would be to pin down the top of the incline on the upper support (by the bridge) and at the bottom and start placing foam blocks underneath and building it up til it touches the incline. Is there a good math way to do this or is it so close just do it the 'eyeball' method?
Also, this incline has the passing track on it. The mainline track has a 22 inch curve radius. I'm new at this so imagine my surprise when I learned my inside passing track can't be a 22" radius also. Not and stay parallel to the main line anyway. I wanted to keep the same radius though so I have more clearance between the two tracks on the curve and that's how I've drawn it out on the benchwork and it looks like it will work fine as it joins back into the turnouts. Am I doing the right thing or is there something I'm missing?
Jarrell
 

phatpony

Member
Jarrell,
It looks pretty. It probably will be better to eyeball your supports, you are only talking 3/4" of change over 5'. Just cut your roadbed, make sure it's flat and not sagging (use a straight edge) and support it as necessary.

Now, I see a potential "issue" that often gets overlooked by people on their first layout (present company included). You have no way to turn your trains around, and run the opposite direction. This be will fine if all you want to do is run in one direction, but you have a couple of spurs that will be difficult to perform switching in without some kind of run around to get the locomotive on the correct end. Either get all the points facing the same direction or put in a run around track, or better yet, figure out how to put in a couple of reversing sections in. I vote for the latter option, it adds a whole new dimension to running your railroad.

Also, It looks like you have room for more industries, unless you are going for the scenic look. Nothing wrong with that, just another observation.

Glenn
 

jacon12

Member
Thanks for the help Glenn, I'll take all I can get. The one 'spur' just to the left of the 0 elevation mark is meant to be a siding for a helper engine though it's not going to be but about half as long as shown here and I made the one right above the red arrow so I could pull the engine straight in then back up the siding. I don't know if thats going to be good enough though. I'm going to put a siding at the top near that number 3 mark that is trailing and will back into an industry there and one just below the number 2 mark right across from the switcher line to go into the area in that lower left corner. Hopefully I can work in another one near the number 3 mark that goes into the oval also. Still, that only gives me about 6 or 7 industries to serve and I was hoping to get in about 10 or so. Maybe thats enough. I'd like to be able to reverse the train but haven't figured out how best (easiest) to do that yet. I'm open to all suggestions.
I appreciate the thought on the incline. With only a 3/4th inch drop I figured the best way was like you said.
Jarrell
 

RexHea

RAIL BENDER
Yeah, I agree with Glen that with that small of increments per foot your method of eyeballing should be good enough. Just set your roadbed up there and shim it until it is true.
The thing you need to watch out for is not starting a transition in grade near the turnout or a bridge. You usually end up with a slight bump and this could be problematic with the loco/cars being at different heights when entering the turnout. Try to make the change in grade small and as far away as possible in the approach to these objects.;) :)
 

Fergmiester

M.E.S.S. Maker
Most of my climbs/declines are done by eye and yes there are dips in the track but when you look at real tracks you'll see the experts have the same problem especially on spurs. If you are concerned about dips use a yard stick or long flexible straight edge that you can use to insure your track is kept straight. I use this method for horizontal as well as vertical allignments.

You can also use the straight edge on the flat to check rise transitions to insure the tranition is gradual and not "stepped"

Fergie
 

jacon12

Member
RexHea said:
Yeah, I agree with Glen that with that small of increments per foot your method of eyeballing should be good enough. Just set your roadbed up there and shim it until it is true.
The thing you need to watch out for is not starting a transition in grade near the turnout or a bridge. You usually end up with a slight bump and this could be problematic with the loco/cars being at different heights when entering the turnout. Try to make the change in grade small and as far away as possible in the approach to these objects.;) :)
Rex, that part about the turnouts being close has me a little concerned. The original plan called for the height of the bridge to be at 3 inches and I was told that wasn't enough so I moved it up to 3 3/4 inches. With it at 3 inches the track then stayed level to far past the turnouts. No problem. But with that 3/4 inch drop from the bridge back down to the level area, and the turnout for the passing siding AND the turnout for the industry siding, I gotta little problem maybe.
Jarrell
 

jacon12

Member
Fergmiester said:
Most of my climbs/declines are done by eye and yes there are dips in the track but when you look at real tracks you'll see the experts have the same problem especially on spurs. If you are concerned about dips use a yard stick or long flexible straight edge that you can use to insure your track is kept straight. I use this method for horizontal as well as vertical allignments.

You can also use the straight edge on the flat to check rise transitions to insure the tranition is gradual and not "stepped"

Fergie
Thanks for the tips, Fergie.
Jarrell
 

RexHea

RAIL BENDER
Jarrell, if you start the rise about 12"- 18" past the turnout you should be just fine particularly with the small grade you will have, i.e. 3/4" in 4 feet.

A 2% grade is approximately 2" per 8feet or 1" per 4feet. So, you should have less than a 2% grade and should be far enough away from your turnout for the transition. The bridge area should be all right with this small grade, but try to take most of the grade out before it gets to it and not have any dip/bumps at any of the joints.

As Fergie said, slight uppsies and downsies shouldn't hurt if you end up having them, but in the regular track only:not at the turnout and not at the joints. Think about this: If you have a locomotive that has entered the turnout and has the front axles level, but the back axles are still in the grade, then the back truck will try to change its angle to match the front truck's angle. This is asking for a derail. I have seen this on a couple of layouts where the guys had started a grade at the turnout and the derails were frequent until they fixed the problem. My layout had the problem of a slight change in grade at the joints that created a dip or a bump. I would get by with this for some loco's, but there were a few that just couldn't take the change. Passenger cars hate these things!:D
 
Last edited by a moderator:

jacon12

Member
RexHea said:
Jarrell, if you start the rise about 12"- 18" past the turnout you should be just fine particularly with the small grade you will have, i.e. 3/4" in 4 feet.

A 2% grade is approximately 2" per 8feet or 1" per 4feet. So, you should have less than a 2% grade and should be far enough away from your turnout for the transition. The bridge area should be all right with this small grade, but try to take most of the grade out before it gets to it and not have any dip/bumps at any of the joints.

As Fergie said, slight uppsies and downsies shouldn't hurt if you end up having them, but in the regular track only:not at the turnout and not at the joints. Think about this: If you have a locomotive that has entered the turnout and has the front axles level, but the back axles are still in the grade, then the back truck will try to change its angle to match the front truck's angle. This is asking for a derail. I have seen this on a couple of layouts where the guys had started a grade at the turnout and the derails were frequent until they fixed the problem. My layout had the problem of a slight change in grade at the joints that created a dip or a bump. I would get by with this for some loco's, but there were a few that just couldn't take the change. Passenger cars hate these things!:D
And I do have passenger cars! I'll try and work this out, I think I can.
Thanks Rex.
Jarrell
 




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