I was lucky enough to live near the Scalextric factory in Westwood, near Margate and a local farmer paid their skip driver to drop the skip in his chalk pit near Monkton. every 2 weeks, we would get down there and raid the skip and try not to get caught.
I had spare tyres, brushes, motors and axles by the tonne, and we would hit lucky when they had a production problem. One time the crazing on the lap counter track did not mould properly, so the skip was full of the hard plastic half length straights. We had so many that we would run the track round my front garden, out the front gate, up the pavement, and into my mates front garden 3 doors up. There was not enough power when it got to his house, so two of us controlled the cars round our garden, then 2 others controlled the cars from a separate power supply at his house. Knowing what I know now, I never realised at the time just how dangerous this was to do, but we got away with it.
Often the plastic would not run properly into the mould, and there would be a load of Mini or Ford Escort bodies with only part of the roof. We turned them into convertibles.
We had so much stuff we could get a bit carried away, for example, if you run the track up the stairs, and put a skid chicane part the way up, covered in vasaline, the car tyres would actually start smoking as you tried to get across it. We used to build hill racing cars to try and negotiate all the obstacles we would put on the track. We even had a 4 wheel drive stretch Escort....