I finally answered my own question. And I got a reply from a UK discussion group.
I was able to borrow a length of code 75 track and try it. All my locos run OK on it, including the 0.043" flange ones. I measured the depth between rail top and the nearest bit of plastic moulding, and it was about 0.050". Apparently, Peco include some information in the packaging of turnouts, and quote 0.045" as the maximum flange that will go throught the turnout.
So all is well, and thanks for the replies.
Paul.
We have a British modeler here. Surprised he hasnt chimed in yet. David Popp also models British OO. maybe he has something about it somewhere. So maybe somebody has tried it. and hasnt appeared here yet
A pessimist sees a dark tunnel
An optimist sees the light at the end of the tunnel
A realist sees a frieght train
An engineer sees three idiots standing on the tracks stairing blankly in space
Yes, I suspect you are right. RP25 has very shallow flanges, but code 75 is 0.005" taller than code 70 so it might just work. I just wondered whether anybody had actually tried it.
The closest in North America is code 70. And flanges have to be close to RP25 or very shallow.
SHane
Does anybody know what the largest loco flange depth you can run on code 75 OO/HO track. I don't care about running through turnouts, etc, but just on straight track. I have a spot where I need to put code 75, and do have some older locos, and can measure their flange size if I know what the upper limit is (I think my largest is 0.043").
Code 75 is a Peco OO track used in the UK and elsewhere, and I don't know how common it is here in North America.
Thanks. Paul.