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Discussion Starter · #1 ·
In the first issue of Hornby Magazine, the laying of straight flexitrack was covered, but this was never followed up with the process for laying curves as stated in the last paragraph of the article. What is the best method?
 

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DT
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You can get a university degree on the science of laying track.

I have a great book on the subject: Track Planning for Realistic Operation by John Armstrong.


See ordering info in the Resources section.

Basically, you determine the radius of the required curve based on the scale that you are using and the type of trains and their speed on you layout - obviously taking available space and terrain into consideration.

Then you design curves, based on arcs of circles. At the intersection of a straight section and a curve, you have to have an intermediate curve to lead into the constant radius curve.

Once I know where the curved flex tracks go, I pin them down, trim the uneven track with a Dremel cutter and then glue or pin down the track permanently.
 

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In depth idiot
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First few times at least, you need a plan to work by. Draw the plan out full size on the surface on which you intend to lay the track. Use a lath of wood with a pencil through a hole, and a nail for a pivot (relocating the pivot for different radii), as a trammel to assist in drawing curves. It is worth slightly off-setting the drawn curve relative to the straight track to which it connects, to allow a smooth transition from the straight into the curve; unlike the 'step change' which occurs with set track curves connected to straight track.

Once you have the plan drawn out, try and locate the flexible track so that a whole piece covers transitions from straight to the radial portion of the curve. The track itself will form the transition between the two if the straight section is fixed, and then the free end of the length of track is brought round to form the radial section. Keep sighting along the track to ensure that the curve and changes to the curve are smooth. When joining flexible track on a curve, it is usually necessary to actually bend a permanent set into the rail, so that there is no tendency to form a 'dog leg' at the rail joint. Putting in this curvature may well prove easier if it is done before trimming the rail to length. If the track layout you need means you end up with a very short piece of track on a curve, better to have two pieces each just over half the length off the full size piece instead.

Don't feel nervous about having a go, it is not difficult, and practice will quickly refine your technique.
 

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Only one thing to add to the good answers above. If you intend to lay flexitrack beow about 24" or 60cm radius then don't! (or at least try to avoid it). Use set-track instead. 4th radius curves go out to about that size. When trying to lay flexitrack to a tight radius then it is all too easy to make a mistake and get part of it too tight.
 

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I know from bitter past experience just how difficult it is to join two pieces of flexitrack on a curve without ending up with a kink at the join.

The only way I managed to overcome this was to tin the end of each rail and the inside of two rail joiners which enabled me to solder the two pieces of flexitrack together within the rail joiner, while they were both straight. This effectively gave me a double length of flexitrack which I was able to lay as a single piece of curved track. It was particularly effective in getting a smoothy, clean line though a double curved 'S' shaped section of track

I'm sure this cannot be the recommended method but it worked for me. As alan says though, it would be good to have an article on this to see how the professionals do it.

Expat.
 

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I used the same method as Expat on 'Pickersgill Junction' and, in fact, joined three metre lengths together with solder at each end of my 16ft oval.
This method has worked very well, together with plenty of track pins. My base is Sundeala with a little Weyroc which I've had for years. Most of the curves are hidden from view by the back scene, behind which is the fiddle yard.
Incidentally, I have a feature which I have not seen very often, an abandoned branch line. This gives me the excuse to hve a 'junction' station and also gives an extra siding before the track has been removed from the ballast just before the bricked up tunnel.
I was thinking of a layout, fully scenic, with all the track lifted and overgrown and the station burnt out and in ruins.
Think of the savings in loco stock, rolling stock and electrics !

Ed
 

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QUOTE I was thinking of a layout, fully scenic, with all the track lifted and overgrown and the station burnt out and in ruins.
Think of the savings in loco stock, rolling stock and electrics ! biggrin.gif

The cost in Silflor long tall grass might be a bit steep though


David
 

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This reminds me i have kink on a curve the little 08's "chunk"
round on that needs attention before ballasting expat has the answer though i suspect soldering the track in its straight form makes good sense
before creating the curve.
 

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Soldering a couple of lengths together is one way around the around the problem. Soldering on a third length may cause difficulties, unless the piece in the middle has the inside rail trimmed to correct length for the curve to be formed ahead of soldering, and is held roughly in shape when soldered, as a soldered in rail joiner cannot slide through the chairs.

What if you really need to put in an insulated rail joiner on a curve though? You cannot solder to it, and it has less mechanical strength than a metal rail joiner, so the kinking is even worse. For this reason, and because soldering the track makes changes to it and reuse of the track that bit more difficult, my preference is to bend the last two or three inches of rail to correct radius, on curved ends of flexible track.

The method is to lay the track piece following the drawn out curve, leaving the final foot unsecured. Take off the end sleeper panel, and gently bend the ends of the rails into a smooth curve of correct radius. My method is by pinching it between finger and thumb, and drawing the pinch along the rail at an angle. Once satisfied with the curvature replace the sleeper panel, and cut rail to length. It is very quick and easy to do with a little practice.
 

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QUOTE (Expat @ 8 Aug 2008, 10:13) <{POST_SNAPBACK}>Thanks 34C. I did try this a couple of times but could never get the last inch or so to curve properly. I'll have to try again and maybe cut off the last inch or so.
Just be firm with it! Trimming both rails is often a good idea to get things as near perfect as possible. This goes against the grain for me, as I am mean beyond belief and want to get 'every inch' out of the track purchased: it is necessary to keep repeating the mantra "a little extra cost for long term faultless running". Also I remember this process being something more of a struggle with code 100, but have used code 75 for years now. SMP code 75 bullhead is really very co-operative indeed, and can actually be shaped easily with the sleepers in place, which is handy.
 

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QUOTE (34C @ 8 Aug 2008, 15:43) <{POST_SNAPBACK}>Soldering a couple of lengths together is one way around the around the problem. Soldering on a third length may cause difficulties, unless the piece in the middle has the inside rail trimmed to correct length for the curve to be formed ahead of soldering, and is held roughly in shape when soldered, as a soldered in rail joiner cannot slide through the chairs.

What if you really need to put in an insulated rail joiner on a curve though? You cannot solder to it, and it has less mechanical strength than a metal rail joiner, so the kinking is even worse. For this reason, and because soldering the track makes changes to it and reuse of the track that bit more difficult, my preference is to bend the last two or three inches of rail to correct radius, on curved ends of flexible track.

The method is to lay the track piece following the drawn out curve, leaving the final foot unsecured. Take off the end sleeper panel, and gently bend the ends of the rails into a smooth curve of correct radius. My method is by pinching it between finger and thumb, and drawing the pinch along the rail at an angle. Once satisfied with the curvature replace the sleeper panel, and cut rail to length. It is very quick and easy to do with a little practice.

***Thats an understatement - I use C&L flex track and BS95R rail (in steel) and use neither soldering nor fishplates anywhere on the layout. Alignment is always pretty well perfect on both curved and straight track... I simply use a wooden block whichslipes between the rails to align them while the PVA glue that holds the track dries, with NO pins, and no prebending of anything - however my radii are admittedly quite generous.

Richard
 

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I find code 75 significantly easier to fit to a curve than code 100. My radii go down to 24".

David
 

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I have found, through pure trial and error, that the most important thing is to avoid starting the curve with a new piece of track. Kinks are avoidable with judicious pinning either side of the join. My loft gets very hot, and very cold, so I have to keep soldered joints to the minimum (I don't like soldering trackwork anyway). I don't think you need to get too hung up over exact radii ... lay it rough & loose and run your most troublesome rolling stock over it again and again, at speed, backwards, pushing coaches and so on. The smoother the 'join' between straight track and curved the better. I have also attempted to lay curved track on a gradient. That IS hard but even with my clumsy fingers it can be done with enough trial and error.
 

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Hi guys, lots of useful feedback there. In the October issue we've started a new series of Beginners Guides and flexi-track will feature in the November issue, particularly as I have lots of trackwork to do myself in the next few weeks.

Cheers,

Mike Wild.
 

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I'm just starting out but have bought a complete set of tracksetta to help me with my curves (and also straight straights), I'm suprised its not been mentioned here.
 

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QUOTE (Dale_the_Noob @ 5 Sep 2008, 08:49) <{POST_SNAPBACK}>I'm just starting out but have bought a complete set of tracksetta to help me with my curves (and also straight straights), I'm suprised its not been mentioned here.
I too am surprised not mentioned. I have been using Tracksetta and find it very useful even if never quite the radius wanted but really good at holding track in gauge especially at 24" RADIUS.

I had also been wondering when next part of the article started in issue no.1 would appear but guess Mike W has more or less answered that.

Best regards
Cliff
 

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Discussion Starter · #20 ·
Thanks everyone, some ideas here I'll be trying out soon, as the straight track is getting dangerously close to the bedroom wall
 
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