PC Mining underground question.

[Fenris]

Usually when I mine it's because I found a node and just mine a pit in that area for easy escape and so I don't have to worry about a collapse.

This time around I want to mine a quarry under my base. I have a 7x7 starter tower base until I'm ready to build a better one. And want to mine straight down from the  center of the tower so I have something to do during the night. If I mine straight down creating a shaft just big enough for a ladder, say 20 or 30 blocks and then start a tunnel off in one direction, do I need to add supports as I go along the tunnel? If I need supports, how often? Do I need to make a ceiling the whole way or can I just make arches every couple of blocks? Or am I far enough down that I don't have to worry about supports?

Thanks,

 

[wizard puke]

I do almost the same exact thing and I just go in a straight line away from the base that goes far enough away to be out of the chunk once I'm far enough underground. I put a hatch at the top of the ladder and when I'm done mining for the night I climb back up and then destroy the top two ladders and replace them with destroyed stone and close the hatch. I usually throw a few airlock doors in the corridor leading away within the reach of the lcb but it's probably not really necessary.

If you mine in a cross hatch pattern nothing really collapses.

 

[FileMachete]

1, 2 or even 3 block wide tunnels don't require supports. Exception being in desert if shallow enough to still be in the sand layer.

Also no issues with a 1 or 2 block vertical shaft down. Just don't interupt vertical bearing for your bases major support pillars.

(might want to go 2 blocks wide as the ladders basically disappear into the side of 1-block shafts. They still work, just looks/seems odd)

I regularly have a large mine underneath my bases. Being extra cautious I mostly build out a 5x5 grid of supporting pylons down a few bolcks below where the ore peters out. Later I'll take those pylons all the way to beckrock, mostly since vertical mining is so mindless and I just nerdpole back up placing flagstone blocks as I go. (5x5 grid is 3 blocks in between pylons. lots of folks use a 6x6 or 7x7 without issue as well)