FREMO end profile and railhead positioning

Hi,

I have been wondering about the FREMO standard end forms: I cannot understand why the drawings of the standard end pieces never show the rail heads? To me the most important thing is to get the rails joined together.

The rail top (SO) is 1300 mm (+/-10 mm) from the floor. To join the modules together one must know the hole positions related to top of rail head (SO). The holes are specified as 10mm diameter, and the joining bolts are specified as M8. This gives +/- 1 mm play. Looking at the prototype railway line's roadbed profile ('querschnitt des bahnkörpers'), one will notice that the sleepers are completely buried into the ballast, and that only the top of the sleeper is visible from the 'oberbau' of the roadbed. The only german prototype drawing of the roadbed ('bahnkörper') I managed to google is this:

formatting link
The same is visible in the NEM 122:

formatting link
Comparing this to FREMO standard end profiles:

formatting link
leads to think that the sleeper is "buried" into the end profile and that the rail bottom should be right on the 195 mm 'line'.

The standard:

formatting link
specifies the sleeper height as 2 mm, and that the end profile height of end profiles B 96 und E 96 must be minimum 104 mm to the bottom of the sleeper. From this one should deduct that the sleeper should be added on top of the end profile, and that the end profile is not the profile of the interface when the module is ballasted and sceniced.

Looking at the photos of PowerPoint shows at:

formatting link
it seems that everyone has understood the end profile in same fashion (sleepers on top of the profile board). For some reason the makers of some FREMO modules I have seen seem to have mis-understood the idea of adding the sleeper height to the profile, and thus have tried to use the profile board as the ultimate module end profile top surface.

Why is it that one should deduct the rail position in the end profile of FREMO module related to the holes of the end profile?

Isn't the relationship of rail heads and fixing holes the most important thing in order to get trains across the module interface?

Should not the finished scenery/ballast surface and rail heads be somehow displayed on the standard end profile drawings?

Pekka Siiskonen

Reply to
Pekka Siiskonen
Loading thread data ...

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.