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Track Layout & Design Help with designing your track work


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Old 12-08-2018, 10:38 PM   #1
ajcooper4
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Default Minimum radius

In a couple of spots on my layout - due to space & height restrictions - Iím down to about 450mm maybe 445mm - Iíve been using a 457mm tracksetta gauge but itís a little out in these two short sections.

Iím going to run my Hornby County of Devon & a nice 0-6-0 with tender, also Hornby. Both locomotives say 438mm 2nd radius minimum. I really wanted broader curves but space is limited. Also, Iím using Peco code 75 flexitrack.

Do you good folks think these locomotives will run smoothly on such a radius or will I need to creep round really slowly to avoid derailment?
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Old 12-08-2018, 10:56 PM   #2
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The only way to be sure is to try them. Such tight curves may just emphasise imperfections in your rolling stock that you might get away with on larger radius curves but you might just be lucky if the rolling stock is in perfect condition.

The only way to be sure is to set it up and try them out.
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Old 12-08-2018, 11:42 PM   #3
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All locos and rolling stock new in last 12 months. Fingers crossed then!
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Old 13-08-2018, 10:42 AM   #4
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It is difficult to bend flexible track to a tight radius without putting a spring in it which may cause the track to lift off the ballast at some later stage.

You can sometimes get away with a 1st radius curve if it is only for a short section. The way to do it is to build the curve with sectional track and test all your locos going round it.

There are two reasons a loco is not recommended for a 1st radius curve - either the wheelbase is too long or parts of the loco will not clear lineside objects.

If the wheelbase is too long, you must fit a 2nd radius or larger curve because the loco just won't stay on the track.

However you may find the loco will go round a tight curve, but it will not clear lineside objects such as bridges and tunnel mouths. You can get round this by moving the object, such as a signal further away from the track.
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Old 13-08-2018, 10:56 AM   #5
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Quote:
Originally Posted by Cudworth View Post
It is difficult to bend flexible track to a tight radius without putting a spring in it which may cause the track to lift off the ballast at some later stage.
Isnít that what track pins are for?

I agree that trying to put a tight curve into flexi can create a tight kink but either use a Tracksetta or draw a line on the board and lay to that, pinning as you go.
You can always pin the track with drawing pins and test it with locos before committing to a final route.
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Old 13-08-2018, 11:55 AM   #6
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I agree Steve M The other point I would make is to pre-drill the sleepers before hammering pins int them. Pushing pins into sleepers can bend them ,7 force the rails inwards. This may not matter as a rule, but here you are working near the possible limits.
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Old 13-08-2018, 12:18 PM   #7
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I always pre drill and as I lay track straight on the board there is no distortion.
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Old 13-08-2018, 12:18 PM   #8
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Thanks for all of this. The tightest radius curves are very short pieces only - a matter of 100mm length at most. Also the tightest radius isn't 438 (radius) 2 is slightly wider at around 450 maybe 445.

Track pins is what I use normally but in tight spots under the eaves (layout is in the attic) there isn't room to swing a hammer! I always pre-drill the sleepers and slightly into the board to ensure the pins don't bend. In one section I've had no choice but to glue using PVA - but this section will be covered with a tunnel so I'm not bothered.
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Old 13-08-2018, 12:19 PM   #9
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Quote:
Originally Posted by SteamnutKR View Post
I agree Steve M The other point I would make is to pre-drill the sleepers before hammering pins int them. Pushing pins into sleepers can bend them ,7 force the rails inwards. This may not matter as a rule, but here you are working near the possible limits.
Predrilling sleepers is a given imho.
In a tight situation like this I would still use drawing pins between the sleepers for testing but then predrill both the sleeper and the baseboard particularly if using the very small Peco pins recommended for N gauge.
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Old 13-08-2018, 12:20 PM   #10
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I would add - I use 1/16 inch cork underlay cut to shape. It just gives a slight noise reduction and feels like it has a bit of give in. Also easier to pin as you get more bite.
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