Have built the main modules for my new ho scale layout, they are all 2’x4’ but now it is time to do the corners. The mainline is 22 radius for curves 3 inches from the front and a dual gauge 3 inches from the back that could be 18inch radius but would like 22 also. Seen a few designs with the Prince William County club being the closest to what is needed but wanted imput before I start, maybe there is a better design out there. Also last I need both inside and outside corners and I know some designs are only good for one or the other, ideas!!!
As you stated your track centers are three inches from the front of the layout on the main line and three inches from the back of the layout on the dual gauge. This by itself well make the corner modules very made (hard) to make. As the corner track on the inside will have to make a turn of three inches while the outer track will make a turn of twenty one inches. Your track should be close to the outer (front) edge of the layout on the outside corners and close to the inside edge (back) on the inside corners. To do this you will need to move the track to that corner before it gets to the corner modules. The modules them self’s are easy, a twenty four by twenty four square. Laying track to meet up with each edge of the other modules with your track layout will not work! You will have to make the inner dual track form a loop at each outer corner and the main form a loop at each inside corner.
But if you have not laid track yet you can adjust your track plan to give each transition section between modules a place to meet at the proper point to give it the broadest curve for that module. For the inside corners this should be done near the back of the module, but on the outside corners it should be done at front of the module.
Found this for reversable corners. Developed for NTRAK but probably can be adapted.
A very interesting concept.
4x4 Then measure in 2 feet on 2 contiguous sides and cut off the corner.
The 22 inch radius curve will take that just fine.
You can even do 3x3 and measure 1 foot in to cut off the corner, but the 22 inch curve will be pretty close to the front edge.
Since the desired radius for both the front and the back is the same and thier location with respect to the edges is the same, the same size module could be use for both inside and outside corners.
D = Depth of the modules
S = amount of straight track on the module edge before you can begin a curve
The minimum size for a corner module would be :
22 + S + (D-3)
So for a 24" module with 4.5 inches of tangent on the edges, the minimum corner would be : 22+4.5+(24-3) = 47.5 inches. 48 " square would work.
Dave H.
Wow, ntrack has some new ideas from when I was a member, way back when. A variation of the revisable 4/5 footer may be what I’m looking for as I wanted to use easily transportable sections and since I am using 2’x4’ 2" thick foam as a base, that kinda works but it might make the track work a nightmare with the crossovers but maybe a variation? It did give me an idea that the Price William Cub’s could be done as two pieces, thoughts?
Thanks for the formula, I’m surprised that I understand it as my math skills are dismal.
You could use your 2x4 foam to make a Diagonal corner unit. Measure 17" from the from to the rear and mark a spot, do the same on the “front” face and connect the dots…cut off that piece and you will have a 24" 45 degree angle to mate with your other 2x4 modules…repeat on the other side and you will have a 90 degree turn. Plenty of room to haveup to 30 in rad curves and the corner unit will stack up in the same space as your other modules.
Have Fun!
Could also use your best 2x4 modual design as only some of them are done.