As you can see if you expand the picture, the pencil mark is in the middle of the 7 sleepers. The frog is well behind that, and is correctly positioned according to the NMRA track gauge. Bugger. I've had to add another sleeper behind it so that I can solder the next piece of rail on behind it. Must check the measurement on the other point.
Next post I'll also describe the method of making the point frogs. Its actually very easy, takes about 10 minutes, and seems to be almost foolproof (last night we just discovered someone had invented a better fool, who I see in the mirror every day)
(Gordon, Graham, if you are reading this, sorry, but its my first attempt, and I'll know what not to do next time :v)
Having said that, its getting oddly addictive, and I'm looking forward to getting a bit more done late tonight.
5 comments:
ALWAYS ALWAYS ALWAYS Place the frog first (But you have probably just figured that out for yourself ;-P ) Even a small error in sideways location of the running rails can affect the position of the frog drastically, due to the quite shallow angle of divergence.
that may work on your system, but this is the way that the local guys do it, and it works in S scale. Its more based around building the track to fit the location, not the other way round as you would if building in a jig.
Just started laying my track of propietry rail(peco medim points) and found that given I measured what the minimum distance of a double track (4 metres between prototype centre lines), how I want them to be layed out I found the points are short for the CL to CL, so I will need to add an extra bit between the points. Given that I found this out for my first modules and others may need to have handmade points.
I was considering the build-on-site factor when making first comment; I'm coming from an engineering assembly point of view, nothing to do with my jig-assembled turnouts.... The crossing/frog is the crucial part of the turnout, so it should really be placed first and everything else located using it as the reference point.
maybe its the different way of doing the whole thing. The local method relies on the track radius rather than the point number (#7 or #9 etc).
as a case in point (haha) my current work involves a crossover with a 1200mm radius. I have no idea what this works out to, and it doesn't matter.
the running rails have to be placed before you can make the frog, which is made from one piece of rail in 5 minutes with no fancy filing jigs, just a vice. the frog is bent but not soldered. The curve templates then dictate where the frog fits, and its pushed into position and only then soldered up.
This might not be prototypically correct, but it produces beautiful flowing trackwork, with no sharp transitions that make large steam locos look so silly going round tight corners.
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