The most important part of any plan is knowing when to throw out the plan.
The small and large mining drill that you unlock in the copper or iron tier respectively are intended to be a good source of resources throughout the early game. While they where never intended to completely replace hand mining at their point in the game they should make it start to feel like you need to do less and less of it. They were not really doing that for a couple of reasons. First they did not mine very many block 400 for the small or 1800 for the large and second they had to be moved way too often.
Woth the idea in mind that I wanted the player to get more resources from their machines I came up with a few options.
1. Make resource finding easier. While it would certainly help you gather more of a specific material if you knew for sure that there was a big copper deposit somewhere there would be nothing stopping you from just mining it by hand. There will certainly be more ways to find out what is below the surface in the future but it doesn't really solve this problem so it will be shelved for a little while.
2. Make resources only drills can mine. Because the Voxel world is of finite height and each block has a reasonable limit of how much resource it can contain and still be balanced it can be difficult to have enough resources to mine in any column of the world for the massive amount required for an automated factory. To that end I could add special objects in the world that could contain any amount of a type of ore. While this would certainly help that is what I tried to do with the latest update to the world generator just in Voxels and I want to keep as much in the voxel world as I can and not just spawn in game objects because it's easier.
3. Mine More Blocks. What is wrong with strip mining the entire planet? It's a video game. If you can mine more blocks easily with the automated mining systems available to you you get more stuff to work with. It adds no complicated extra game mechanics and you get to feel like you have a bigger impact on the world.
So the player needs to be able to mine more blocks and the old 2x2 and 3x3 mining drills were not going to do it. Quarrys are in for both copper tier and iron tier. The copper quarry can mine a 7x7 100 deep over 12 times the number of blocks as the small mining drill. The iron quarry can mine 11x11 200 blocks deep over 13 times as many blocks as the large mining drill. Both the copper and iron quarries have a rotation input for power and take a similar amount of power as their respective drills did. The steel quarry still exists in nearly the same form just with a rotational power input to match the other two. Quarries will be unlocked in exactly the same place as the old mining drills and have the same cost.
I hope this helps you harvest as much resources as you need and will be coming in the version hopefully next week.