Factorio Golem achievement

So I sort of replayed the time I would spend playing world of tanks with playing factorio and as such have been smashing out the achievements and was down to the last three.

Lazy bastard that I find odd as it will take more time and effort to do, Mass production 3 where I need to produce 20M electronic circuits that will take a bit of time and of cause course Golem where you need to survive a 500+ damage but I was stumped.

I tried the running in a biters base with mk2 armour and mk2 shields to no avail but it was fun. I then did a quick search and people were saying maybe get hit by a train so gave that a try and failed. I then put 15 mk2 shields on my mk2 amour and bingo that worked so well it stops the train but did I need 15 mk2 shields? no it is more like 7ish but I guess it comes down to how fast the train is going so save before impact just in case lol