Hi,
I’m planning my “dream” layout which will have a 2% grade in it. In an effort to have a smooth transition to the grade I was thinking that I would start the grade midway through a piece of flex track. Is this possible or will the track simply not bend that way? I’m just trying to avoid the uneven edge that can happen when you have a piece of track at the end of the grade meeting a piece of perfectly flat track. Thanks.
Flex track can be bent into a grade transition, but make it gentle. A sudden change will be a source of derailments.
Put it this way, if you do have a problem, your transistion is a little too abrupt.
This should work just fine.
You have it exactly correct. Not only is it OK to start the grade in the middle of the flextrack, it is the best way to do it. If you must start the grade at the end of a piece of flex, solder the joiners first.
Definitely don’t start the transition at the joint!
This is one of the least understood areas of gradients and a good question. You’re right to call it a transition and you have 2 of them, one at the bottom and one at the top. For a 2% grade you can have as much as 3% in the middle and 1% or less in the transitions and end up with a 2% average grade. The key is that grades are averages, you can’t abruptly have 2% at the beginning or end. It can be an exponential graph on both ends. One trick I like to use is buy a set of shims from the hardware store. They’re usually over a foot long and gain a little over a 1/4". Use them at the top and bottom to get the transitions STARTED. I don’t necessarily lay track on them, they help me establish the roadbed placement. The growth of the grade of the transition areas are really limited by the length of your rolling stock. The longer the rolling stock, the more transition length you need.
Richard
Keep in mind that forming a smooth transition is more about what’s under the track than the track itself. As others noted, you’re doing it right to avoid a track joint right at the transition and put the track centered in the length of flex. The subroadbed it’s in contact with can aid in making a smooth transition. I use 3/4" plywood, which tends to be overkill, but which naturally lends itself to a smooth transition because it resists overflexing and tends to give a smooth transition with no aburpt changes. Other materials require somewhat more attention but work successlly with care.
Mike makes a good point. To add to it, it is more important to avoid a subroadbed joint at the start of the grade than it is to avoid a track joint.
The other advantage to 3/4" plywood is that you can’t bend it enough to create a problem so you don’t have to worry about watching the details of the transion.
Yes, I would start a grade away from any track joints and make the transition gentle. I found that my 1/2 inch plywood subroadbed always provided a pretty gentle easment into a grade. You don’t want joints in the plywood very close to the transition, either.
I have several grades on my layout and since I use OSB subroadbed and Homasote roadbed the Homasote makes the perfect transition over the OSB.
I can start the grade and not have to worry about the placement of the OSB subroadbed.
The Homasote will bend easily and will self support across the start point of the grade.
The Homasote will always be a smooth transition.
BOB H - Clarion, PA