Not quite the full story that though is it? If had used large radius points from the off, similar in length and radius to a B6 EM point, I wouldn't have had the issues I've got (well, had at any rate!)
True, but you wanted to use the small radius points to maximise the space, and couldn't, so you have had to compromise already.
There would still be issues with the amount of slop in the standards, which are best addressed by using a combined coupler/buffer (e.g. tension-lock, knuckle, what have you.
It has also been suggested that you might want to spring your buffers: yet another complication on a simple project
All I've really done is establish a set of parameters within which it can be made to work (in terms of my layout scope) - if had started with this knowledge, half this thread wouldn't have happened
And, if I can be slightly flippant - trotting down the the local model shop and handing over some readies ain't exactly difficult (and easier than building 3 EM turnouts).
True, but it wasn't your intention to trot down to the shop and hand over some cash: this has cost you unplanned money as well as time: it is no longer the cheap quickie you intended. If you had stuck with tension locks, it would have remained true to your aims.
Once I'm up and running, I'll test with the stock I have available and confirm whether propelling reliably with something like the front overhang of a Black 5 is possible, or indeed, not. At least if someone else starts down this route its possible to prove by example the likely issues and restrictions that need to be applied.
I suspect that it will work, but not 100% of the time.
Going OT here...
We must not forget the original reasons "00" came into being in the first place, both related to the use of German made toys for H0.
Firstly, the mechanisms would not easily fit into a British outline body at 3.5mm scale;
Secondly, it was not possible to get the motion onto a model within the loading gauge, as the wheels were rather coarse and already close to 4mm scale over the outer faces, so increasing the scale made sense as it made the toys look less awful.
Now, I know that a prototype tolerance of, say, 5 thou cannot be practically scaled down by a factor of 76.2, and will mostly end up being a 5 thou fit, so it would be a very interesting game trying to do absolutely everything to exact scale (if done perfectly, it wuld seize up!), but practically speaking, if one adopts wheels to a finer profile and fits them to the B2B required for "Universal" B2B, then the width over the outer faces of the wheels will be less than scale: creates a poor visible impression, but on the plus side, lots of clearance behind cylinders to accommodate sharp curves.*
Back to the original reasons for 00: small mechanisms are no longer an issue, and have not been for a long time.
A narrower wheels set to a much narrower than scale B2B looks odd when viewed low-down and head-on, and also under the footplate.
Narrowing the gauge to reduce the slop is a retrograde step - it is akin to the old Hornby Mk 3 coaches with only 7 window bays and also requires hand built track - and narrowing the flangeways simply involves handbuilding track again, and adjusting if not replacing wheels.
CJF wrote, when I was 10, about this issue in "proprietary to scale" in the Modeller, and he gave I think a very good definition of the word scale in our context: "not a toy". In this context "fine scale" (two words, note!) makes sense - it means even less like a toy. Narrowing the gauge to reduce slop in the track whilst maintaining compatibility with RTR wheel standards is a good engineering solution, but it is a move away from scale, and certainly not a "finescale" or "fine scale" move. Narrowing the flangeways whilst keeping the gauge constant simply means as much work as switching to EM, which latter is a fine scale move as it gets things closer to scale.
Don't get me wrong, I have no problem with people doing what the hell they like - it is a hobby - but I simply cannot see (or will not accept!) that "finescale 00" is possible, except as a shorthand description for EM (and in which case, why not call it E?) I had no problem with 10mm scale and 45mm gauge track, for example, except that a simpler, and better scale - 1:32 - pre-dated 10mm scale. I also have no problem with Universal 00, particularly when playing with my son's trainset with tension locks and 17" radius curves (but I think the LGB has more play value).
Depends on whether you need to mention EM on here again
What's wrong with EM? Plenty of EM on here, and more power to its practioners' collective elbows, say I. I didn't
need to mention it: it simply naturally follows as the sensible finescale compromise between ultra-scale and scale models, at leat for 4mm scale models of 4'8.5" prototypes.
Give me "American 00" anyday! (4mm scale, 19mm gauge.)
* There are more things I could say related to this, but perhaps it needs a new thread?