Lgb track planning query

[a98087]

Hi All

While currently planning/building my railway, Ive come up with the following track plan, and just want to check that the track centres work out.

Also the plan involves an r5 point which i havent yet purchased.

Ive included 2 photos, one showing actual track, the other a quick sketch in paint.

The sketch is as follows:
Blue R5 curve or point
black R3 point
Red 300mm straight
Yellow 1/2 R5 curve

The actual track layout on the ground

And in case any wonders why im doing it this way, is its a quite a bit cheaper than buying lots of r5 points, but it still retsins nice gentle curves

Dan


Any thoughts, comments gratefully recieved,

 

[Gizzy]

I would use Anyrail software to draw this, then clarify the track centres.

As you are using a mix of R3 and R5, you have to consider the arc angles; an R5 point is 15 deg, but an R3 point, or curve is 22.5 deg.

You will have to there fore swap the red straight and the yellow 1/2 R5 curve as shown here. Grid is 10 cm....

 

[a98087]

Thanks gizzy, that photo is soooo much clearer that what I did,

All I have to do now is work out. What length of track to put between the r5 point curve/ and the r3 to sort out the track centres

 

[Gizzy]

Thanks gizzy, that photo is soooo much clearer that what I did,

All I have to do now is work out. What length of track to put between the r5 point curve/ and the r3 to sort out the track centres

Tell me what track centres you require and I'll draw it up on Anyrail for you....

 

[a98087]

Cheers gizzy, Im just after the standard lgb 185mm spacing.

 

[Gizzy]

Cheers gizzy, Im just after the standard lgb 185mm spacing.

Here's the LGB track geometry chart.

http://theworldoflgb.blogspot.co.uk/2010_08_01_archive.html

I don't think you will get 185mm spacing if you mix R3 with R5, for the reason given earlier of the different arc angles.

To get the R5 arc of 15 deg to the R3 arc of 22.5 deg, you will have to add a 7.5 deg curve. LGB make such a curve (an R1 1/4 curve), which is useful for joining R1/R2 points/curves(30 deg arc) to R3, or R3 to R5 points curves, BUT you are adding in a short extra length of track when you do this, and correspondingly, your 185 mm MINIMUM track centre spacing will be larger.

I'll have a look tomorrow (Friday) afternoon, when I'm up and about after my week of Night shifts, and see if I can do this with the AnyRail software, but thinking mathmatically, I don't reckon we'll get the 185 mm centres required by mixing R3 points and R5 curves....

 

[Gizzy]

Well following on from my last post, where I thought getting 185 mm centres with r3/r5 track combinations was going to be nigh on impossible, I solved this particular geometric puzzle on my first attempt! :thinking:

I added two R1 1/4 curve LGB 11040 either end of the R3 point, which increases the arc angle of the R5 sections from 15 to 22.5 degs, the same as the R3 arc.

I've set the grid lines for 185 mm and the track centres are bang on the line!

And no dog leg on the centre road either....