Help with Triang back to back distances.

[cypherman]

Hi all.

Can anyone tell me the best back to back distances for Triang engines circa 1955-65 to run on code 100 track. I am having some derailing problems with the main wheels derailing on the point frogs with some of my locos. The 3mt 2-6-2 seem to be the worsed for this.. I am using set track points.

[andyman7]

It will depend on the exact age and make of the track (for example, Peco Code 100 points from the 70s have more generous clearances than modern Peco Code 100). However, where I have had to gauge Triang era wheels to run on Code 100 I always aimed for around 14.1mm if that helps.

 

The other thing to take into account is the extent to whether you get general derailing or a specific location - the latter normally benefits from some forensic analysis of the underlying factors (track level, geometry etc) 

[Il Grifone]

I have never seen a figure for the correct back to back for Tri-ang. The wheels are however designed to be the correct value if pressed hard against the shoulders of the axles or with the wheel/axle units pressed together. Tri-ang standards are rather on the coarse side for today's set track*. Once they became Hornby, they adopted the Dublo setting of 14.2mm. (check gauge 15mm). I'll dig out a set and measure them.

 

The problem could be the deeper flanges causing a bump as they pass through the frog?

 If my 3MT is anything to go by the tyres are rather square which certainly does not help.

 

*Peco or Hornby?

Edited December 26, 2022 by Il Grifone

[cypherman]

Hi all,

Thanks for this info. All my engines that I have restored and run use the later spoked wheels with the shallower flanges. The points are 1980s Hornby set track points. I was also wondering if some of the wheels may have expanded due to Mazak rot. Can you also please tell me what the width of the wheels should be for both the flange and wheels.

Edited December 26, 2022 by cypherman

[stewartingram]

I use Peco code 75 track on my (unfinished) layout - no fiddle yard yet! However it is possible to run on the layout that is laid. I am modelling East Anglia transition period, but have a large collection of locos collected since the early 60s (far too many in fact!) A small number of these still use old Triang chassis, which (contrary to popular opinion) WILL run through code 75 points. I have (easily) adjusted the b2b on these until they do, though tbh I have never measured it. 

Edited December 26, 2022 by stewartingram

[ikcdab]

To be honest, the actual back to back is not the important component.

The key measurement is the check gauge... That is the distance from the running face of one rail to the inner face of the check rail on the other rail.  Your wheels should be set to just clear this distance.  Measure a few check gauges with you calipers and see what they reveal.  If they are wildly different then your track is the problem.  If they are largely the same, then add on a quarter of a mm or so and that is what you back to backs should be.

As is said above, you need to look closely at what the exact problem is.

Ian

[33C]

4 hours ago, cypherman said:

Hi all.

Can anyone tell me the best back to back distances for Triang engines circa 1955-65 to run on code 100 track. I am having some derailing problems with the main wheels derailing on the point frogs with some of my locos. The 3mt 2-6-2 seem to be the worsed for this.. I am using set track points.

I have noticed that the 3MT can be a pain through points. I cured mine, after trying finer wheels etc, by filing down the flanges on the original wheels by 2 mil and setting the back to backs at the original factory width. The improvement was quite dramatic!

[locomad2]

I just pull the loco wheels out using a wheel puller, test by pushing the loco over points 100 peco and see if it gets stuck or jump over frog and test rail.

 

With older wheels ones that slide on axle just pull them apart and jam a bit of plastic between 2 half's

 

Peco 100 points over the years have changed a lot older ones had quite wide frogs

[GoingUnderground]

I think Zinc pest or rot is rare on Triang locos of that period in my experience, unlike British Trix. Ex-works flange thickness is probably the issue on points catching the check rail, combined with the depth of the flange being such that it is running on the sleepers on code 100 track.

 

In the 55-65 period Triang was still aiming for the toy market, not the scale modeller, and reliable running on loose lay track on the floor was still paramount. 

 

[Il Grifone]

For the later Hornby wheels (Dublo standards), the flange should be 0.8mm thick. This gives a check gauge of 15mm, which is correct for BRMSB standards also, (I'm ignoring finer standards as these really require finer wheels (preparing for objections!).

 

The wheel thickness is not really critical (as long as it's not too fine), but should be of the order of 1/8". Ready-to-Lay points of sharp radius have a continuous curve through the frog and tend to have the closure rails out of line with the crossing nose which results in the flange hitting it, if the B2B is too large.

I don't think I have any Hornby wheels here, but I'll check.

 

EDIT:

Rereading I realise this is rather irrelevant to the question in hand which involves Tri-ang wheels. However the later open spoke ones have rather nasty square tyres (and too many spokes - a common failing). I have replaced all mine with Hornby wheels.

Edited December 27, 2022 by Il Grifone

[roythebus1]

Triang back-to-backs were variable on rolling stock as one wheel was free to move on the axle!

[DCB]

Don't slag off Hornby Dublo.  Their trackage was 21st century with flange bearing switches, the flange supports the wheel across the rail gaps on crossings.  H/D stock on H/D points run beautifully, as they do on Peco.  BUT only IF you pack the Peco flangeways so they support the flanges...

 Triang  The plastic wheels in the metal chassis stock with open axle boxes slide but they won't slide freely enough for Peco Code 100 set track points. I press the axles out put a small washer (8ba?)over the axle  between the wheel halves and press back together again.  That gives about 14.2mm B to B which gets most early plastic wheels through peco streamline code 100, a few have huge flanges and are best binned, and the Transcon tiny ones often distort and don't run true. 

I made a 14.2 mm template or three to fit Hornby Dublo wheels which I use for everything else on the layout, Go / No Go  if wheels fit the 14.2mm end but not the 14.75mm they are good.  The Mazak  driving wheels can be filed so their flanges go through P4 points, or have no flanges at all. The hard sintered large flange ones will file grooves in your file, best binned, the ones with separate tyres suffer with loose tyres which move inwards so you can't get the B to B right without pushing the wheels out,  which  means taking a wheel right off and adding spacers other wise the pickups force loco to one side  .   I used to fit Romford tyres when they were affordable, but it's a real problem trying to keep the Triang /Hornby era locos running, almost all mine have had Romfords, Hornby Dublo or later Hornby driving wheels fitted, just the floor ones which use super 4 remain standard,  I try to fit spacers each side of the main drive gear within the chassis which improves the slow running and stops the plastic insulating bushes wearing away.  A set of Markits wheels and axles is expensive, but it should last 50 years and I don't think todays China stuff with plastic gears will be running then.  On the other hand I won't be around in 50 years either,  decisions decisions.

[Il Grifone]

I have had the problem of Tri-ang 10mm wheels warping - they probably had a large stock of acetate ones to use up! This is not a problem, as they go straight to bin along with the bogies!

Anything with early coarse/square Tri-ang wheels gets new wheels at least. Only 'collectible' items are exceptions, but these are shelf/display fodder!