Hi!

Märklin made models with a length of 303 mm in a set of three - DB double stock coaches 43597.
Schürzenwägen and Umbauwägen from Märklin are 1:87 - so are the Pike coaches and other models of older rolling stock.
ICE 1, 2, and 3 are too short, but I think that Thalys and TGV have the correct length. There are some 292 mm SNCF/SNCB coaches in 1:87, too.

Märklin compromise length, width. and other details (length of trucks, position of pivot points, ...).

Some locos also have reduced length.

Sometimes they write 1:93.5 in the catalogue while items actually are 1:97.5.

A diner of 27.5 m leads to 316 mm model length.

I have 303 and 316 mm coaches from Roco. I have 303 mm coaches from Piko and Trix. There are other brands like LS Models and ACME.

See also:
https://www.marklin-user...ength-Scale-Mystery.aspx
https://www.marklin-user...eal-life--1-1#post488010

At a club meeting I ran 303 mm Piko coaches and 303/316 Roco coaches on R1 C track (360 mm) without any problems.

And that was to my surprise because I equipped the Piko coaches with the additional door steps from the goodies bag. Theoretically you need at least R3 C track to operate those coaches with door steps.
Minimum radius at home is R2 and I tested with one Piko coach whether or not the door steps can be used on R2.

Minimum radius for the Märklin/Trix 303 mm coaches is 360 mm.

All this with standard close couplers. The guiding mechanisms of those coaches usually can handle the 358 mm radius from the two-rail world.

Märklin makes models that work well in the artificial environment found on most, if not all model railway layouts. Our layouts are in general very, very far from actual scale dimensions and it seems odd to me that we still expect the trains to be made to a perfect scale.

IMO If you primarily collect trains to look at them in static settings, then by all means only buy those models which are to perfect scale. I see this as a very worthwhile pursuit, although it is not mine.

If on the other hand you buy trains to run and enjoy them, then buy ones that work well and don't obsess about perfect scale. This is simply a different worthwhile pursuit and it is mine.

We have lots of choices. Make the ones that work the best for you and don't forget - HAVE FUN. After all that is what this hobby is all about!

I am really happy with the choices that Marklin makes with regard to coaches. The only true scale coach I ever owned was an Orient Express sleeper from ACME. I was going to buy the whole set until I realised that it hit the m-track turnout lanterns.. So it was sold.. While I run the longer trains on the R2 (outer) track, I have run the Thalys in the R1 track - it really does not look good going through R1 curves..

Modern coaches are "all plastic" with a metal piece in the bottom to add weight - applies to Märklin, Piko, Roco and probably many others, too.

Add-on parts with Roco vary from "none" to "many". I don't have issues with them falling off when trains derail.
Some Roco coaches are actually Fleischmann coaches in Roco boxes. Well, some Märklin coaches are actually Fleischmann coaches in Märklin boxes.

With coaches, the height is not compromised AFAIK.
I have the latest Märklin Popwagen set which includes a full-length full-width dining coach along with "new longer length" coaches that have compromised width and length.
The dining coach is much wider then the other coaches. I know the proportions are wrong and I notice this when I see the "fat" diner between the "slim" coaches.
The diner is wider in real life, but the proportions are wrong.

The Roco RAm has full length and the powered car looks very impressive - longer than most other locomotives.
With the Märklin RAm each coach is too short by about an attoparsec and the powered car only has the length of many other uncompromised locos.
Thus things that are special in real life look ordinary as a compromised model.

I actually have the Marklin variety of that one together with some extra caches but I dont recall ever having run the the thing on my layout when I still had one.

What is an attoparsec? (a google search did not help)

I have the same set. The dining coach is around 34 mm wide, which corresponds fairly to the prototype that is around 3100 mm wide.

The standard UIC coach is 2825 mm wide giving us a model that should be around 32 mm wide. The Märklin coach is 30 mm wide (or almost an attoparsec ). This makes the difference 2 mm or 0.08 inches. Given the some what true to width dining coach the difference is noticeable because 1 mm is missing on each side if you look for it. My experience though is that nobody ever really does. I had never thought of it before you mentioned it.

Compromises all the time. No body ever questions the width of the sleepers on the C-track. Those too are actually 2 mm too short.

Tom, I attend a lot of forums, I almost never see this written as much as comments about the coach lengths. It is my understanding that the majority of customers are unaware of this fact. Yes, some do not like it, but "many" as in "I see this all the time" is hardly correct.

atto is a metric prefix (like milli, kilo, centi) and is 10^-18: centi, deci, milli, micro, nano, pico, femto, atto. It is a really really small portion of something....

Parsec, on the other hand, is an length measurement - on astronomical scale. So you talk about parsecs when discussing interstellar distances. Specifically a parsec is defined as: One parsec is the distance at which one astronomical unit subtends an angle of one arcsecond. An astronomical unit is the distance from Earth to Sun. A parsec is about 3.2 light-years.

Applying that very tiny portion to a very large areas... gets you the attoparsec.

3.08567758149137×10^16 meters (the parsec) * 10^-18 (the atto scale) = 3.08x10^-2 meters or about 3.08 centi-meters.

IE someone was being a bit silly ;-)


PS for the Star Wars fan you will recall Han Solo's bold claim he made the Kessel Run in under 12 parsecs... as in, he was able to get from A to B in less than usual distance. One assumes the distance would be a straight line to begin with (that the Kessel Run is 12 parsecs long) and this is somewhat odd.. but then in a universe with hyperdrive, bending space-time isn't unusual. But on a model train layout an attoparsec is always 3.08cm, even on Han Solo's Märklin layout.

Hi Mike:

I think that the first assumption that people make is that a model is fully rendered in a given scale.
Some models, eg Roco's Exact Scale or LSM, ACME, etc have all aspects rendered in 1/87.

Other models have compromised scale, which means that although the model is rendered for use on HO, it has some variances. Most frequently, this is seen in terms of scale length. The width and height are still rendered in 1/87 so that the coach/car is not too narrow or too short.
Maerklin decided to produce it's newest long coaches in the scale of 1/93.5. However, due to the fact that this is the longest length that can safely use their R1 curves with catenary, turnout lanters and signals, they also render longer coaches (e.g. restaurant cars) to the same length as the others, so some have taken to describing the Maerklin scale length as 282mm. In order to facilitate the operation on tighter radii, Maerklin has also compromised the bogie reproduction, rendering the bogies with an off centre pivot, which reduces the overhang of the coaches.

Maerklin's decision to model prototypes less than 25m in exact scale and those over that length in reduced scale length can make for complicated modelling. For example, the DB or FS (UIC-X) coaches are 1/93.5, but the SBB lightsteel coaches are 1/87. I now have the new 43874 SBB diner which is also 1/93.5, so that helps, but there are no other SBB coaches in that scale for Era III/Early Era IV.

I use a second such diner car with my SBB and FS Eurofima consist, which is all 1:93.5.

The exact scale length Lightsteel cars can be combined with Lima, Roco and other SBB passenger coaches (EWI/EWII) which is cool. Unfortunately the Maerklin models of those coaches have some rendering errors which some Swiss train fans find irritating.

I have the 1980s Roco models of the SBB EWIV in 1/93. They have a length of 284mm. I tried to combine them with the new Maerklin coaches, but the Roco coaches are a little wider than the Maerklin ones. I am not sure who has the correct scale width.

What irks me is that in addition to reducing the scale length as a compromise, Maerklin (and other companies) also have to reduce the scale of other details, like windows and doors, in order to fit the correct number of compartments into the reduced length. In more than a few instances, the company's designers rendered the whole window (width and height) instead of just the width, resulting in a less than pleasing appearance, where the windows are either sitting too high or too low depending on the model. Some paint jobs, e.g. TEE red and beige or DB blue and beige make the placement of the windows stick out like a sore thumb.

Too low (42991 Bar coach): http://assets.catawiki.n...e5-8025-552e5e7655a6.jpg
or: http://www.lokshow.de/sp...nwagen/bilder/42991d.jpg
Too high (26557 Restaurant): https://www.marklin-user...ls/mike%20c/DSC02695.JPG

Regards

Mike C

I had also been thinking to hide the majority of the curves in tunnels.....

Nice plan!

Reminds me of an article in a Hewlett Packard Journal where they gave the area of a microprocessor chip they built in nanoacres.

With Märklin this is quite simple.

Let's take #43308 as an example.
On the top of the product description it says "Design type 1:87". This applies to the tracks and the height of the car.
Further down the page it reads "1:93,5" - this means nothing as the length of the coach is 1:97.5. I don't know which scale applies to the width of the car.

The Märklin engineers can give you the scales for any dimension and any part with two decimal digits. They published some figures for the ICE 3, thus revealing that not much of it is really 1:87 (but earlier catalogues advertised 1:87).
The Märklin marketing department simplifies the numbers shown in the catalogue, rendering them completely useless because some numbers were generously rounded while other numbers are simply typos.


Roco don't show more care when making catalogues. Their 316 mm dining coaches are often advertised as 303 mm in the catalogue. So you don't get the advertised length, but you get 1:87 in length.


With all those inaccurate information in the catalogues, things can be confusing - not just for new customers.

Before building a layout, decide whether you want to use long coaches (316 mm and such) and either place signal and catanary masts accordingly -or restrict yourself to 282 mm coaches to avoid problems with masts close to the track on the inside of curves.

Thanks, I kind of suspected that their info would be inconsistent and not too accurate.

Will be going for the larger radii only so that should give me some flexibility.

The vast majority of Roco coaches runs on R1 if the layout has sufficient clearance left and right.

If you want long scale models, build a layout with suitable clearance left and right.
Or run shorter coaches that suit the clearance of your layout.

Do not blame Roco for making scale models if your layout has extremely small radii with insufficient clearance. Scale models from Märklin will have the same problems.
Shortened models from Roco, Piko, and Fleischmann should work as well as shortened Märklin models.

A small Noch layout with short platforms might be a good candidate for Donnerbüchsen and Umbauwägen. Märklin make them in 1:87.

The builder of a layout has to make some compromises - but can make some choices. Decide for or against 316 mm coaches before you start building a layout. That's my point.

Vehicles to scale: apply easement curves

All,

in my opinion vehicles of different scales in one model train does not look good. Hence I avoid this.
As most model engines are to scale, I only have cars that are to scale. One can have almost any car to scale. However märklin does not offer many passenger cars that are to scale.

A home layout often cannot be made without small radius curves.
The offset between the ends of cars on small radius curves will be greatly reduced when one applies easement curves.
Flex rail can be laid according a spiral or klothoid.
With industry track one can achieve an easement curve by starting a curve with a track element with a large radius followed by one with a smaller radius and so on. Example: straight – R6 – R5 – R4 … R4 – R5 – R6 –straight.

For better looks of your model train also avoid laying S curves. Always have a straight piece of track in between.

Regards, Willem