A few thoughts on gauges for track assembly

[Budgie]

Even on the prototype, coning/steering works only on very gentle high-speed curves. On sharp curves and most model curves, one wheel must slip to follow the difference in lengths between the inner and outer rail.

The prototype tries to ameliorate this slipping by using flange lubrication, which isn't done on the model, maybe because it's not needed.

[bertiedog]

The noise from the tyre is separate to the flange, which is lubricated over complex pointwork, I used to wonder why over complex pointwork approaching Charing Cross the squeals varied, and it the difference between the tyres slipping slightly and flange squeal, some of the junctions are very tight indeed.

A bit different from 5 inch gauge live steam, where some favour flat tyres, on the argument that the aluminium track develops a flat top, which it does from very large locos with flat tyres using it. They say it increases adhesion and to seems to work, as the load in people is easy to check.

 

Stephen

[nswgr1855]

No point(Sic) in showing the points or the track, as a wooden gauge and a brass one give EXACTLY the same results, the gauge is correct or it is not correct. The usefulness of a pin gauge is that the nails are easy to file to the correct width for the flangeway.

Any wooden gauge would be checked before use!

 

A gauge is 0nly correct when it produces track that is within the limits of the standard being used.

On wheels going around a curve, if the tyres are flat, then the inner one journeys a shorter distance than the outer, one must slip. In real life on the railway the curves are gentle and elastic effects in the rail compensate and slip does not occur that much, but can set off screeching noise from the tyres,

 

In  theory coned wheels and inclined track top overcomes the problem, if the track is correct and the wheel unworn and to perfect standard profile..

 

With models though you are in the hands of the gods as to what taper is there or whether the top of the rail is inclined (as in DCC).

 

The self steering and the diameter difference on the wheel are swamped by other factors, like the slack in bearings allowing the axle to run out of true etc., etc.,

 

All these little points add up to explaining why some makers just get "bad" points, constant jittery running, stalls, and unneeded roll etc.,

 

Mind you, if you want such track and the look of an old industrial track..............

 

I have no trouble running wheels with no tread taper on my H0 track.

If you get "bad points" it's about the dimensions of the turnout not being compatible with the wheels on the models, in other words, the turnout is out of tolerance.

 

Cheers,

 

Terry Flynn.

[nswgr1855]

Oh gawd, now you've done it....

 

Gordon S, sitting happily building 00-SF pointwork using a check rail gauge, 1mm shim and a 16.2mm track gauge.  Also enjoying every word and standing back in admiration of the combined knowledge of those contributing to the topic.

 

.....and not a bump or click to be heard or felt....

 

 

Well done Gordon, Strange thing, using my "in tolerance" metal roller gauges, I get the same result.

 

My speed tests are as follows. My fastest Steam locomotive is a Hornby LNER P2, 2-8-2 with a Hattons DCC decoder fitted. Maximum scale 00 speed through complex track work on a H0 12 chain scale curve was 86 00 scale mph, light engine forward and reverse. My layout speed record holder is a DCC fitted Lima/Joef 8 car H0 scale TGV with no coning on the wheels, cookie cutter flanges. Maximum scale speed through my complex track work was 224 H0 scale Km/h (140mph). I do not dare to do these speeds on the recycled RTR turnouts made in Japan from 30 years ago in my fiddle yard. The "normal" maximum speed for the locations I am modeling is about 60km/h (37mph).

 

Cheers,

 

Terry Flynn.