Welcome to The Lego Car Blog’s latest comparison of old and new Technic models; this time, excavators. Some genres of Technic model age better than others – a 1977 tractor is every bit as good as a 2012 one, and better than those in between – whereas others, I guess, just need a bigger parts palette to look and work right.

There’s a reason why excavator models were very rare from Lego until very recently, but it can be done with the old stuff. The blue machine in the picture above is built from instructions in the (completely wonderful) 8888 ideas book, published in 1980, and using only parts from that era. It’s movements are cunningly controlled using only racks and gears (lots of gears..) and it works OK, if not brilliantly. Cute, though. If it was a set from 1980, it would merit at least a 6/10.

Lego didn’t attempt an actual excavator set until the advent of pneumatics in 1984, with the 8851.

It’s the red beast on the left, and it looks like a step up from the blue one.

It isn’t. The problem was the early single-outlet pneumatic pumps. These extended under pressure, but returned via vacuum, controlled by a block of one way valves plumbed in between pumps and switches. This tortuous system had to be crammed in to 8851’s compact body, and unless you were VERY careful, there would be kinks in the pipework. (TLCB Top Tip: instead of using 8cm and 6cm grey tubes between the 3rd switch and the valve block, use 6cm and 4cm. They’ll be crushed a bit less.) It also made it that rare thing; a Technic model that’s not fun to build. Continue reading →