Humming wagons

[Reorte]

A train of MMAs passed me at New Mills Central the other day, and they were making a rather odd electrical-sounding humming noise. Is there anything powered on these, or just an odd effect of the bearings or track? It was decidedly strange! The 66 on the back was a bit unusual for trains I've seen around there too, although I guess that could just be to save a light engine move, move a broken loco, or to save running around somewhere.

[eastwestdivide]

The loco each end could indicate it was on its way to/from engineering works where it needed to go both ways in a posession.

Don't know about the hum. The "binliner" trains can hum a bit in hot weather, but that's a different kind of hum!

[scouser]

Humming. Probably didn't know the words...

Where's me coat?

[stewartingram]

From what I've heard of modern wagons passing through Ely, I'd say it was roller bearings on the modern stock.

 

Stewart

[Fat Controller]

From what I've heard of modern wagons passing through Ely, I'd say it was roller bearings on the modern stock.

 

Stewart

Amplified by the resonance of the wagon body.

[Steadfast]

The modern stuff as it gets going does seem to make a noise not unlike the "traditional" sound of electric traction motors, an increasing in pitch with speed.

It may be the older stuff does too, but the other running noises drown it out. You certainly notice the difference between the new wagons and the older O&K stock on the Mendip trains in noise levels! The bogies under these new wagons are called LN25s, LN standing for low noise. Threw is nothing electrical on the wagons, save, at a push, the earth straps

 

Jo

[roy h]

by any chance did this train have a 60 on the front as saw a similar one passing woodley last week and according to realtime trains was going to a somewhere in manchester but can not remember where. thought it strange myself the noise it was making but put it down to the hot day

[Mark Saunders]

I find that this hum is found track that has had attention from a Rail Grinder!

 

Mark Saunders

[Ncarter2]

I find that this hum is found track that has had attention from a Rail Grinder!

 

Mark Saunders

Also rail grade makes a big difference, especially to freight wagons. HP rail sings very well.

[Titan]

I find that this hum is found track that has had attention from a Rail Grinder!

 

Mark Saunders

 

I suspect that this is the right answer! The rail grinder leaves lots of small grooves perpendicular to the rail head, which would account for the hum. I have heard HST's make this weird humming noise too, they never used to and their design has not changed. I suspect other passenger stock does too but it is drowned out by the noise of the under slung engines...

Edited April 29, 2018 by Titan

[Reorte]

by any chance did this train have a 60 on the front as saw a similar one passing woodley last week and according to realtime trains was going to a somewhere in manchester but can not remember where. thought it strange myself the noise it was making but put it down to the hot day

Yes, 60 on the front, 66 on the back. Trains to and from Peak Forest are good ones for seeing 60s. No numbers I'm afraid.

[robertcwp]

This was a chance capture on my phone on a windy day, but you can hear a humming sound from the wagons:

https://youtu.be/NQALmnHPeaw