R2 / R3 dilemma

idlemarvel

idlemarvel

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13 Jul 2015
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To cut the the chase, does anyone have or know of pictures or videos of an RhB themed layout using LGB R2 curves? That would help me greatly. If you want to know why read on.

I have an indoor layout with limited space. As a result I use R1 curves and points throughout. This has served me well and I am happy with the ability to run trains every day to offset the lack of space indoors. Up til now my favoured theme has been East German 750mm narrow gauge. Most LGB locos, carriages and trucks of that theme run well on R1 and don't look too silly. 2-axle trucks and carriages are short wheelbase and run fine. Long carriages and truck are bogied and don't have any issues with R1. Most locos, steam and diesel, run okay, exceptions being Rugen 0-8-0 (grinds the curved track as it goes) and Harz 2-10-2 (ridiculous overhang). Even my VIK 0-10-0 manages okay thanks to the articulation in the chassis. So far so good.

Recently I got hooked on RhB (metre gauge). This is a whole new ball game when it comes to R1. Many (most?) of the shorter trucks and carriages are 2-axle long wheelbase which let's say don't enjoy running on R1. Bogie trucks and carriages are very long , 600mm or more, which have ridiculous overhangs on R1 curves and points. There are some short locos (Ge 2/4s for example) but even they have a quite a long wheelbase and my Gea 2/4 "flatiron" does noticeably slow down on R1 curves. I look in real and virtual shop windows at Ge 4/4 and Ge 6/6 locos but realise they are far too long for R1 curves even if they would in theory run. Don't even think about Allegras! This is not really surprising when you consider the prototype. The rolling stock on the RhB is nearly as big as standard gauge. If you see pictures of the inside of modern RhB carriages it is hard to tell them from mainline stock. Same for the container wagons.

The solution is obvious - move to larger radius curves. I can fit R2 curves in comfortably and at minimal cost and inconvenience, although I would have to simplify my layout. I can fit an R3 circuit inside my shed, but that would require major reconstruction of the inside of the shed and rather more cost implications. So R2 would seem to be a good "half way house" between R1 and R3. But as anyone who has studied LGB track radius numbers, R2 is not half way between R1 and R3. R1 is 600mm radius, R2 is 780mm and R3 is 1200mm, so while R3 is twice the radius of R1, R2 is only 30% bigger than R1. (BTW I realise there are other brands that do a proper "half way house" of 900mm but that would require the same amount of shed reconstruction as R3. And there is always flexitrack, I'm just using "set track" for convenience in explaining the problem.)

So to my dilemma. LGB R2 would clearly be better than R1, everything would run better, and I could make the change relatively quickly and easily. My dilemma is, would long locos, wagons and carriages look any better on R2 than R1 given that it is only 30% bigger? I have seen pictures and videos of (indoor) LGB RhB layouts using R3 and everything runs and looks good, but I have not been able to find the equivalent with R2, hence my question. I realise this is a nice problem to have and a rather subjective one, but a problem shared is a problem halved as they say. Thanks for any thoughts or comments.
 
a98087

a98087

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8 Nov 2009
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Like you’ve worked out R1 and r2 are similar, basically r1 is approx 4 ft radius and r2 is approx 5ft,

Another issue is Lgb Dont make r2 points, so depending on your track plan that is another potential issue.

It might be worth looking at maybe piko geometry to see if that has any answers.


Dan
 
Greg Elmassian

Greg Elmassian

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I really don't think you will get a marked "visual improvement" from a 30% increase.... normally double is the noticeable one, 100% increase.. this is 3 times the increase from R1 to R2...

My "common wisdom" to people in the "tight space dilemma" is figure what you can do, and then push it to the next larger curvature. Has served me and my friends well.

Greg

p.s. good "point" on the points sizes Dan
 
Gizzy

Gizzy

A gentleman, a scholar, and a railway modeller....
26 Oct 2009
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PIKO R3 is smaller than LGB R3 and it will fit within it, being radius is 922 mm or 36 1/4 inches in old money. Zerogee has apparently done a double tracked section on his railway with both types of 'R3' I believe? PIKO R5 is equivalent to LGB R3.

I have used some Trainline R2 points on my layout with R1/R2 double track, which I guess can be brought from GRS now that Glendale Junction have closed, and I think it would be your nearest dealer too Dave....
 
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Greg Elmassian

Greg Elmassian

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8 Mar 2014
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Pick your diameter/radius

Diameter
Feet
Radius
Feet
LGB
R
Number
Piko
radius
feet
Train-Li
diameter
feet
Train Line 45
diameter
feet
Aristo CraftUSA Trains
42R1R1 4'4'
52-1/2 R2 R25' 5'
63 R3R3R3
6-1/2~3-1/4 6.5'
84R3R5 R4 8' 8'
94-1/2 9'
10 5 10' 10'
10-1/4 ~5 R7
11-1/2~5-1/2 R4 11.5'
12-1/26-1/4 12.5'
147 14'
157-1/2R5 15'
168 16'
16.5~8-1/4 16.5'
2010 20'20'
 
P

Paul M

Registered
25 Oct 2016
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Royston
Use flexible track, you may be able make suitable "custom" curves
 
PhilP

PhilP

G Scale, 7/8th's, Electronics
5 Jun 2013
24,915
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Tamworth, Staffs.
Certainly, a 2-10-2 still looks terrible on a R2+ curve.. :(
 
dunnyrail

dunnyrail

DOGS, Garden Railways, Steam Trains, Jive Dancing,
25 Oct 2009
16,306
1,049
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St.Neots Cambridgeshire UK
To cut the the chase, does anyone have or know of pictures or videos of an RhB themed layout using LGB R2 curves? That would help me greatly. If you want to know why read on.

I have an indoor layout with limited space. As a result I use R1 curves and points throughout. This has served me well and I am happy with the ability to run trains every day to offset the lack of space indoors. Up til now my favoured theme has been East German 750mm narrow gauge. Most LGB locos, carriages and trucks of that theme run well on R1 and don't look too silly. 2-axle trucks and carriages are short wheelbase and run fine. Long carriages and truck are bogied and don't have any issues with R1. Most locos, steam and diesel, run okay, exceptions being Rugen 0-8-0 (grinds the curved track as it goes) and Harz 2-10-2 (ridiculous overhang). Even my VIK 0-10-0 manages okay thanks to the articulation in the chassis. So far so good.

Recently I got hooked on RhB (metre gauge). This is a whole new ball game when it comes to R1. Many (most?) of the shorter trucks and carriages are 2-axle long wheelbase which let's say don't enjoy running on R1. Bogie trucks and carriages are very long , 600mm or more, which have ridiculous overhangs on R1 curves and points. There are some short locos (Ge 2/4s for example) but even they have a quite a long wheelbase and my Gea 2/4 "flatiron" does noticeably slow down on R1 curves. I look in real and virtual shop windows at Ge 4/4 and Ge 6/6 locos but realise they are far too long for R1 curves even if they would in theory run. Don't even think about Allegras! This is not really surprising when you consider the prototype. The rolling stock on the RhB is nearly as big as standard gauge. If you see pictures of the inside of modern RhB carriages it is hard to tell them from mainline stock. Same for the container wagons.

The solution is obvious - move to larger radius curves. I can fit R2 curves in comfortably and at minimal cost and inconvenience, although I would have to simplify my layout. I can fit an R3 circuit inside my shed, but that would require major reconstruction of the inside of the shed and rather more cost implications. So R2 would seem to be a good "half way house" between R1 and R3. But as anyone who has studied LGB track radius numbers, R2 is not half way between R1 and R3. R1 is 600mm radius, R2 is 780mm and R3 is 1200mm, so while R3 is twice the radius of R1, R2 is only 30% bigger than R1. (BTW I realise there are other brands that do a proper "half way house" of 900mm but that would require the same amount of shed reconstruction as R3. And there is always flexitrack, I'm just using "set track" for convenience in explaining the problem.)

So to my dilemma. LGB R2 would clearly be better than R1, everything would run better, and I could make the change relatively quickly and easily. My dilemma is, would long locos, wagons and carriages look any better on R2 than R1 given that it is only 30% bigger? I have seen pictures and videos of (indoor) LGB RhB layouts using R3 and everything runs and looks good, but I have not been able to find the equivalent with R2, hence my question. I realise this is a nice problem to have and a rather subjective one, but a problem shared is a problem halved as they say. Thanks for any thoughts or comments.
Not sure if you have ever seen the Ruschbahn but this was a Swiss based layout that was using R2 in places that were not seen IE in Tunnels. Outside it was mostly Flex to a good gradual radius. One of the Termini was indoors and here we used LGB R3 points and even a Double Slip which has mixed Rad I believe. Though the Crocks and. 2/4‘s negotiated it we never tried the 2-8-0. Most of the Station was otherwise straight in an overlong Garage, not much help for you I am afraid. It is just one of those things that even with a larger space compromises generally need to be accepted. The Ruschbahn was an imaginary line with links to the RHB thus plenty of RHB stock to be seen, most of the Wagons were LGB standard Opens and Box Cars suitably painted and re-lettered with a few Bogie Wagons for Log Traffic and Sand Traffic in Bogie Opens. No reason why you should not do a similar thing with perhaps small 4w coaches and shorter wagons with retired RHB Locomotives.
 
idlemarvel

idlemarvel

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13 Jul 2015
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Thanks for all your thoughts and comments, all very helpful. More cogitation required.
FYI regarding the lack of R2 points, the TL-45 ones are their interpretation of R2, 900mm.
Weiche rechts 90cm , ohne Antrieb
However Bertram Heyn makes LGB standard R2 points, 780mm rad and 330mm long, see here:
Die Modellbau-Werkstatt Bertram Heyn: Alles Schöne für die Gartenbahn. Bausatz Zungenweiche R2, 22,5° Abzweig links, Länge nur 330mm!
They are 22.5 degrees unlike LGB R2 which are 30 degrees, but he also sells a 7.5 degree R2 to make up the difference.
 
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Brixham

Brixham

No buffers were hurt at this sign
27 Aug 2010
1,164
11
Mr Hacksaw can be your friend!

I've make three one third R3 sections from one ( damaged is better ) standard LGB R3 curve, these then can adapt R3 points/curves into R1/R2 geometry

Malcolm
 
idlemarvel

idlemarvel

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13 Jul 2015
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Indeed Malcolm. I have considered chopping and bending 30 deg R1 (of which I have plenty) into 22.5 deg R2. Whether it is worth the effort is another matter! :)
 
idlemarvel

idlemarvel

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13 Jul 2015
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As a paper exercise I drew a range of curves (R1, R2, 900mm and R3) with my CAD program and superimposed a long-ish loco, a Ge 4/4 ii which is 570mm long (over buffers) and 118 mm wide to see how it might look.
(note the 900mm circle is not concentric with the others).

loco.jpg


The "cross-hairs" are my estimate of where the bogies are. You can see with the R1 curves the corners of the body are in the middle of the track, and the centre buffer well outside the track, nearly beyond the edge of the sleepers. With R2 the corners are just about within the track, probably would be as the actual body would be about 15mm short of the buffer length. The central buffer would be outside the track. With 900mm (such as TL-45 or Piko) it fits quite comfortably, and R3 more so.

Then I thought I would try adding a long coach, 680mm, such as a Bernina panorama coach, shown in blue below.

loco_coach.jpg


With R1 curves the track is exposed on the left side of the coach, and again the corner of the coach is in the middle of the track and the buffer nearly beyond the sleepers. With R2 it is not so bad, the corner of the coach and central buffer is just about inside the track, and the centre of the coach on the left hand side only exposes sleeper ends. With 900mm and R3 the situation is better but not dramatically so.

On the basis of this paper exercise it looks like R2 could be bearable, although I don't think I'll be investing in a rake of panorama coaches just yet! :)
 
Bill Barnwell

Bill Barnwell

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Here is a diagram of mixing different ones
different radius_s.jpg
 
Greg Elmassian

Greg Elmassian

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Yes, but mixing the curves actually makes the problem worse, as the curvature changes throughout the curve. Mixing R1's into a curve makes it just as tight there. Some people like the idea since it is an easy way to make a curve fit an area with sectional track, but if you are anywhere the limit of the rolling stock it is a bad idea.

this is not transitions in and out of a constant curve, those are very good.

Greg
 
idlemarvel

idlemarvel

Neither idle nor a marvel
13 Jul 2015
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Thanks Bill that's a helpful chart. I agree with Greg though, if you end up with more than one R1 in the mix you are not really avoiding the problem I am trying to fix. In that regard your 2000mm diameter which is basically R2 with transition curves could be handy. If you want to stick with set-track then introducing non-LGB 900mm radius into the mix could be useful. Thanks again for your input to my mild dilemma!
 
idlemarvel

idlemarvel

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13 Jul 2015
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As someone mentioned that a Harz 2-10-2T still looked ugly on LGB R2 I thought I would model that in the same way.
The model is 55cm long. Because of the way it is constructed, the model pivot point is quite close to the front. I don't have one, but I understand the first three driving wheels are fixed, the rear two pivot, and the rear pony pivots on that. Then you have the extended bunker at the back, as per the prototype. This is why you get the outrageous overhang on R1 curves. As before the diagram shows from top to bottom, LGB R3, 900mm radius, LGB R2 and LGB R1.

2-10-2.jpg


You can see with R1 the corner of the bunker (right end) is almost outside the track. With R2 the bunker corner is on the middle of the track but the central rear buffer is beyond the end of the sleepers. I think this ties in with PhilP PhilP 's observations. Not much better with 900mm, you would really need R3 to make this visually acceptable IMO. I hope if/when LGB produce a Saxon 2-10-2T they use the VIK chassis where the pivot point is central.
 
AustrianNG

AustrianNG

Director of my railway
16 Sep 2015
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Wirral
Go with as big a radius as you can - if you don’t (you are at the crossroads so to speak) you may always having that nagging thought in your head - why didn’t I do R3 ?

I have put a spiral on my new layout - it’s a mix of R2 at the top and R3 on the steeper lower sections.
Off to the right of the bridge is a station there is also a R2 curve in this shot. My Mh6 can’t traverse R1 due to its articulation so on my old layout there where sections of it the loco couldn’t go but my new layout only has a single R1 point on it in the storage sidings.
83890F7C-FB02-404C-9C54-A80617D4E152.jpeg
830DF2BB-BCF4-4F6F-B8C1-095A7C569D98.jpeg
 
idlemarvel

idlemarvel

Neither idle nor a marvel
13 Jul 2015
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Thanks for the input AustrianNG AustrianNG and I do like the spiral. I have more or less decided to move off R1, the only question now is R2 which I can do with minimal expense and current baseboards, or R3 (or 900mm) either of which will require major re-working of the inside of the shed (like removing inner wall and closing off doors) and new baseboards. I don't really have time for the latter this year as I have my work cut out rebuilding the swimming pool (ah such is life!) and other outstanding projects, so I either live with R1 until summer 2021 (when I REALLY retire) or try R2 in the interim.
 
korm kormsen

korm kormsen

Registered
24 Oct 2009
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talking specially about indoors now.
you will never have enough space for decent looking curves (or do you own an empty hangar?)
from my point of view the second best option is, to make curves as needed tecnically, that your roling stock does not derail.
then disguise these curves.
i use belly-bent curves that are between R1 and R2 (R1.5?) and where ever possible i built a mountain with a tunnel over them.
or they disapear behind dense woodland.
 
P

playmofire

Registered
23 Oct 2010
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so I either live with R1 until summer 2021 (when I REALLY retire) or try R2 in the interim.
You never REALLY retire, Dave. Retirement is 24/7 every day of the year and you never have time to do what you want.