Hornby TT120 B2B under size

[philsandy]

Anyone experienced the back to back dimension being out on any Hornby TT locos or rolling stock?

I have been building 12mm gauge points to NEM 110 standards, using code 60 rail, plywood sleepers and plastic chairs. When I started all I had to check the pointwork was a two axled wagon (not Hornby ), which ran through very smoothly.

When My Hornby A3 Night Hawk arrived I decided to test it by just running the tender through the pointwork as they are not wired up yet. It would not go through them at all, the B2B were out. They should be between 10.2 mm - 10.4 mm, and they were around 10 mm, one axle was 9.8 mm.

After adjusting the B2B's the tender ran through very smoothly. On checking the actual loco these were also under, again around 10 mm. Have not adjusted these yet.

Edited March 15, 2023 by philsandy

[SGF]

Hi, Are the track components from the 3mm Society?

[NCB]

How are you measuring them. Top quality tools needed. 

[philsandy]

On 18/03/2023 at 13:56, NCB said:

How are you measuring them. Top quality tools needed. 

 

Digital vernier, and a 12mm Intermediate B2B gauge.

[NCB]

Tried a digital vernier, sometimes checking with a micrometer, and found neither was good enough. Bought  a Moore & Wright micrometer  which was.  

Edited March 21, 2023 by NCB