Paul Willis
On Bob Allison said
Hi Paul,
Good to hear from you again; after your post on 3rd July I feared that you might have abandoned this forum altogether.
Firstly, in fairness to you and the P4 chappies (I was one for 30 years and am still a member) I have never heard any of them claim to get anything right to a hundredth of a millimeter. 18.83 is a nominal dimension.
That said, I think most if not all would agree that the official EMGS standards are more forgiving of errors than P4. Take back-to-back for instance: with accurately laid track and tyre profile as per official drawing, the back to back can vary between 16.25 and 16.65 without derailment (albeit with slightly rough running at the extremes). Of course, the track will never be perfect, so this 0.4mm tolerance might better be viewed as being shared between track and wheels. Also, EM flanges are nearly twice as deep as P4 flanges, so there is more tolerance in level.
Which leads me to a serious point – anyone contemplating “Manchester” or “Pendon” wheel profiles and track standards needs to accept that they are forfeiting most of those tolerances, and their workmanship will have to be of a higher order in consequence. If that’s your bag, splendid, go for it! Your track will look better than mine. Personally, and at risk of being considered disloyal to this society, I would wonder why not go the whole hog and choose P4 (maybe with EM profile wheels – Martin Goodall on the Scalefour Forum has done exactly that, and it seems to work well for him.)
Regards,
Bob
Morning Bob,
I haven’t abandoned the EMGS forum. Although the sheer user-unfriendliness of the experience means that I visit it less. And I certainly aren’t going to bother trying to make long posts with pictures again. It’s just too frustrating to do.
Although in the spirit of trying, here is one of the pictures that I was going to post to that thread. It’s of an EM wheelset on some EM gauge track built with 2mm rivets:
Anyway, I just wanted to say that I completely agree with you – no matter whether it is EM-SF, or P4 or whatever, it is always a trade-off between the visual appearance and the ease of construction and use. I’ve always been happy with P4, but moving to the finer tolerances of S4 (a la Ray Hammond and a couple of others) has always scared the life out of me.
You mention Martin Goodall’s approach of EM wheels on P4 track. Of course, that is “EM-fine” wheels like Gibsons or Ultrascales. You would never get a Markits wheel profile or a pulled out OO RTR wheel through P4 flangeways. But it does make a lot of sense if you’re not a hair-shirted purist. The track, which is always on view, is to prototypical standards and looks better, whereas the wheel flanges that appear only when rolling stock is present, and are generally hidden under some gubbins, are less noticeable as to being overscale. It makes sense to me, even if it is not the path I chose many years ago.
I’ll keep an eye on what is happening over here occasionally, even if the forum does tend to log me out when I’m not looking. And I’ll stick a post over in the Coffee Lounge in a moment…
Take care,
Paul