Ok, so I take it you want to prevent pigmen/magma cubes/ghasts from spawning.
You'll need to do this in an area out to a radius of 128 blocks from where you plan to stand while AFKing at your wither farm to get the best results. It's actually a sphere, but most of the time it's easier to just pretend it's a cylinder (unless you like maths :-) ).
In the nether, half slabbing is probably the most obvious option, I suppose you could use lava, but that would likely lead to massive lag due to lots and lots of flowing lava (not sure though). Half slabbing is the most common method I see used though.
For finding caves ... once you've got the majority half slabbed out, you could wander around listening for pigmen sounds. They should spawn fairly quickly in caves once you start reducing the surface level area available. You probably don't need to get em all though. But if you miss some, you'll probably notice your wither farm slowing down over time.
Ok, so I take it you want to prevent pigmen/magma cubes/ghasts from spawning.
You'll need to do this in an area out to a radius of 128 blocks from where you plan to stand while AFKing at your wither farm to get the best results. It's actually a sphere, but most of the time it's easier to just pretend it's a cylinder (unless you like maths :-) ).
In the nether, half slabbing is probably the most obvious option, I suppose you could use lava, but that would likely lead to massive lag due to lots and lots of flowing lava (not sure though). Half slabbing is the most common method I see used though.
For finding caves ... once you've got the majority half slabbed out, you could wander around listening for pigmen sounds. They should spawn fairly quickly in caves once you start reducing the surface level area available. You probably don't need to get em all though. But if you miss some, you'll probably notice your wither farm slowing down over time.
I actually have to say in the nether a combination of TNT, withers (with beacons) and haste beacons for mining are the fastest. If you have a lot of ground area, I've found it's actually incredibly easy to just summon 1-3 withers, depending on how many you can handle, and just make sure they aggro on you, then run around with speed effects, ender pearls, and some splash heal potions (beacons recommended and strong armor is an unlisted given). The withers make quick work of the netherrack because of it's weak blast resistance, and if you're good at staying alive (punch II bow hint hint) you can actually get loads of exp from all the quartz. A haste beacon works as a great cleanup crew.
Finally, the caves. Caves in the nether take ages to find, which is actually one of the downfalls of building over a lava ocean; it sucks to find the caves under it. And yes, there are caves under lava oceans. It sucks. A lot. That's where we used TNT. I basically just put on some blast resist armor, filled my inventory with ender pearls, lava buckets, and a few stack of TNT, then went ham under the lava oceans. I'd recommend using lava to fill up the caves, it's faster than half slabbing, but make sure to be thorough, as the lava doesn't go everywhere you need it too without some coaxing.
Another advantage of blowing up everything is it looks super impressive, but that's not what I'm getting at. If I recall correctly you get better rates if the area is cleared out (might be changed), but that's how it seems to work for the farm on my SMP. We built the wither wiper, and it gives us about 1 skull a minute. Nowhere near as fast as the 4.5 skull per minute like the ZipKrowd version, but it's still awesome.
Took about 12 hours to do, would have taken eight if we knew what we were doing.
So, I'm working on building a wither farm in the nether and was wondering about spawn busting the surrounding area to improve efficiency.
Specificaly:
How many squares out do I need to spawn bust my mob farm?
Is there an easier way than slabs to spawn bust in the nether?
What's the best way to find and/or deal with potential caves/cavities?
Channel
https://www.youtube.com/user/Tyken132
My Blog/Forums
http://tyken132.com/
Ok, so I take it you want to prevent pigmen/magma cubes/ghasts from spawning.
You'll need to do this in an area out to a radius of 128 blocks from where you plan to stand while AFKing at your wither farm to get the best results. It's actually a sphere, but most of the time it's easier to just pretend it's a cylinder (unless you like maths :-) ).
In the nether, half slabbing is probably the most obvious option, I suppose you could use lava, but that would likely lead to massive lag due to lots and lots of flowing lava (not sure though). Half slabbing is the most common method I see used though.
For finding caves ... once you've got the majority half slabbed out, you could wander around listening for pigmen sounds. They should spawn fairly quickly in caves once you start reducing the surface level area available. You probably don't need to get em all though. But if you miss some, you'll probably notice your wither farm slowing down over time.
Thanks so much for your help. I found something on the wiki about mob spawning and such but it wasn't overly clear on the concept.
Also, great idea on finding those caves. Not sure it'll help for deeper once but I doubt those will be much of a problem.
Channel
https://www.youtube.com/user/Tyken132
My Blog/Forums
http://tyken132.com/
There is no fast way, tho if you build over a large lava lake you will have alot less work to do
I actually have to say in the nether a combination of TNT, withers (with beacons) and haste beacons for mining are the fastest. If you have a lot of ground area, I've found it's actually incredibly easy to just summon 1-3 withers, depending on how many you can handle, and just make sure they aggro on you, then run around with speed effects, ender pearls, and some splash heal potions (beacons recommended and strong armor is an unlisted given). The withers make quick work of the netherrack because of it's weak blast resistance, and if you're good at staying alive (punch II bow hint hint) you can actually get loads of exp from all the quartz. A haste beacon works as a great cleanup crew.
Finally, the caves. Caves in the nether take ages to find, which is actually one of the downfalls of building over a lava ocean; it sucks to find the caves under it. And yes, there are caves under lava oceans. It sucks. A lot. That's where we used TNT. I basically just put on some blast resist armor, filled my inventory with ender pearls, lava buckets, and a few stack of TNT, then went ham under the lava oceans. I'd recommend using lava to fill up the caves, it's faster than half slabbing, but make sure to be thorough, as the lava doesn't go everywhere you need it too without some coaxing.
Another advantage of blowing up everything is it looks super impressive, but that's not what I'm getting at. If I recall correctly you get better rates if the area is cleared out (might be changed), but that's how it seems to work for the farm on my SMP. We built the wither wiper, and it gives us about 1 skull a minute. Nowhere near as fast as the 4.5 skull per minute like the ZipKrowd version, but it's still awesome.
Took about 12 hours to do, would have taken eight if we knew what we were doing.
Helpful
Cheers, ~Fugu