Back in the day.....

[Old 97]

I used to run a homebuilt "magnetic" car around the layout.
There was always something on the bottom of it when it came back into the yard.

 

[Mixed Freight]

Did the same with my N-scale. Rare earth magnets make short work of finding anything within a few inches of the track!
O-gauge no problem either. Especially with the postwar locos and their Magnetraction. They seem to find anything and everything, too.

 

[migalyto]

I used to run a homebuilt "magnetic" car around the layout.
There was always something on the bottom of it when it came back into the yard.

It will collect all those lost coupler springs!

 

[Old 97]

Dude! There was track nails, little pieces of steel from the real scrap loads.
Plus, things I didn't recognize.

 

[NorthBrit]

Back in the day eh!

Letting the imagination run away ----

A 0 gauge, green 0.4.0 clockwork locomotive and two tinplate carriages travelling an oval of track laid on the carpet. 'Flying Scotsman racing north to Edinburgh'.
'The best train set ever'