Garden Railway Forum

My Railway is nominally set with minimum radius curves of 38 inches. This is fine for my stock and locos, and all can negotiate the track without problems. However, when others come to run on my line, a couple of the curves, whilst, as I said, nominally 38 inches, obviously only average 38 inches, with two spots in particular where the curve is much sharper!
An additional problem is that all my ballast is fixed down with SBR, and that seems to be almost 'permanent' once set. however, this weekend I have decided to address the most troublesome tight spot, near my bridge.
Removing ballast set in SBR
This was actually easier than I feared. It did require the use of a chisel (I use an old 1" wood chisel, rather than a 'cold' chisel). Using this it was possible to release the track from the paved area in question. Once the track (peco, in my case) was lifted, it was relatively easy to pick it clean of residual ballast and dried SBR. So the good news is that SBR is a good fixative, being very solid and hardwearing once dried, but it can be removed if needed.
Track Re-alignment
This photo shows the old alignment of the curve (I forgot to get a before picture ) with the old permanent way removed and the new alignment in place. I used a metre rule pegged at the axis of the radius to gauge my curve (with the aim of keeping to 39 1/2 inch radius). This composite photo shows the ruler being laid against the curve. I also took the opportunity move a short radius 38" point (switch) further from the curve in question, and replace it with a 60" radius point instead. The result is a much smoother curve, even for my stock, and a less ferocious transition from the point, where there was a nasty reverse curve, which also caused some problems. The only issue with this is that it has drastically shortened the passing loop, so similar replacement will take place at the other end, but further down, to restore the loop length.
All I need to do then is reballast - it's surprising how 'flimsy' the permanent way is before the ballast is fixed.
And this will also leave me with 2 short radius points - for which I have a cunning plan...

It is worth doing these forward fixes once a line is built as it results in better running sessions.

That is a very good report on the use of SBR as it obviously does its job but is not beyond removal if required.... something I haven't attempted myself, yet!

Hi Phil,

As Peter says, a good report.

It's a very nice piece of permanent way work too, if I may say so. The improvement is clear, the old track shadow proves that. A well, and practically engineered, solution. Well done.

Andrew

Good job. I am one who enjoys seeing track alignment being modified when necessary to ensure better operation.

That looks to be much better geometry, Ian. Interesting that the SBR comes off fairly easily.
As an aside, Peter Butler is rightly normally warning of the need to protect SRB from rain for several days after ballasting. I had to do some patching yesterday and in this weather it was rock solid in about 3 hours!

That looks much better Phil! I should explain to the rest of the forum that the necessity to do this work is partly my fault, last Monday Phil had a steamup and my run was unfortunately rather short as my Beddgelert could not be persuaded to go around the section which has just been relaid. I think it should go round quite happily now.

Phil,

Did you use a template to form the curves? What do you use to bend your rails?

Ian

Thank you all for the kind comments. Don't feel bad Christopher we'd already discussed needing to change the geometry of that curve on a previous steam up - you just added the required impetus!
As for curve bending Ian - I use a Mk 1 belly, which is probably why the curve displayed that randomness which gave me average curves of 38" instead of precise curves of 38"!
I think a curve template would actually be the best option to avoid these tight spots in future. For now, my metre rule will have to do!

Lonsdaler wrote: ↑Mon Jul 09, 2018 7:53 am Thank you all for the kind comments. Don't feel bad Christopher we'd already discussed needing to change the geometry of that curve on a previous steam up - you just added the required impetus!
As for curve bending Ian - I use a Mk 1 belly, which is probably why the curve displayed that randomness which gave me average curves of 38" instead of precise curves of 38"!
I think a curve template would actually be the best option to avoid these tight spots in future. For now, my metre rule will have to do!

Thank you Phil. I think I will either use a template, or set track for my curves. I understand set track is 38" radius. My loco's will go round 24" curves according to Roundhouse. Not sure what radius my Mk1 belly is! I don't like to measure it!

Ian

I am soundly slapping myself on the forehead!
I stupidly purchased 2 replacment wider radius turnouts without first checking what I needed (obviously, I clearly thought, I need a left and a right, right?
WRONG!
I need 2 lefts, because of the configuration of my loop, and I only discovered this when I went to relay the other end of the loop this morning
Fortunately Track Shack have agreed to exchange the turnout for me
Anyone would think I wasn't involved in laying the original loop. Lesson for next time - always double check requirements before ordering. Never assume!

I pre-shape track before installing, prevents 'dog legging' and the track being under constant tension when screwed into place (may bow later on with change in temperatures).

I bought a 'Blizzy Bender' when they were available for bending track, however, you can now buy rollers from GRS to make your own:

http://www.grsuk.com/Rail-Bender---Tenm ... ONLY-M5203

These could be then installed into metal plates and put in a vice to adjust the required radius then run the rail through the rollers.