Looking for clarification on Mob spawner

[KoncreteLiquids]

Been watching videos and getting different "opinions" but I can't get a solid answer... I found my first skeleton spawner and I am trying to find out exactly how far away I need to be standing to spawn them quickest. 16tiles? 19? Both of those seem to be popular....

I dug out 17x9x5 rooms so I could do the 8blocks water on both sides push to middle then 2 deep under the to push them to a water-vater... but I need to knows where to make my elevator so I can drop them (21 blocks) at the right spot so I can grind for enchants

 

[Ashzification]

It sounds like you have all of the maths done already

 

[nicktonton]

Are you using Buildcraft or a mod with similar items to Bc obsidian and regular transport pipes?

 

[KoncreteLiquids]

im using the basic FTB pack with compactsolars

 

[nicktonton]

I made an imgur album demonstrating an easy way to farm drops from a spawner block. It uses Buildcraft pipes, but it can be arranged to work in vanilla, it just gets a little more complicated in that way.
http://imgur.com/a/S3SAE

Now that I'm re-reading the original post I'm seeing that you want to farm exp, this method only gets the drops. Still, it can be modified with a water-vater and some thinking to where the spawning area takes up much less space than a 17x9x5 room.

As far as spawner mechanics go, you must be within 16 blocks of the spawner for it to be active. It will spawn mobs in an 8x8 square around itself. Obviously the spawner block cannot be centered in an 8x8 space, the first step of my album demonstrates how to find the 8x8 spawning area.

 

[KoncreteLiquids]

This is what I modeled up... The white square on the right is exactly 16 blocks from the "spawner" and you stand on a wood block in from of it so you are eye level with the spawner and 15 blocks away.
http://imgur.com/xMa7i

The drop is exactly 20.5 blocks, I have a halfslab for them to land on so they land 1.5 blocks higher then my feet pos. From what I have read the halfslab there ill prevent the archers from ever firing at you a single time.
http://imgur.com/cOZr4

The "inside" of the pool area will be 9x9x5 with the ceiling in place.
http://imgur.com/QHZkb

This looks to be the "standard" xp farm as far as I can tell and from everyone's numbers. and I hope it doesn't look too bad

 

[Gewitters]

I made an imgur album demonstrating an easy way to farm drops from a spawner block. It uses Buildcraft pipes, but it can be arranged to work in vanilla, it just gets a little more complicated in that way.
http://imgur.com/a/S3SAE

Now that I'm re-reading the original post I'm seeing that you want to farm exp, this method only gets the drops. Still, it can be modified with a water-vater and some thinking to where the spawning area takes up much less space than a 17x9x5 room.

As far as spawner mechanics go, you must be within 16 blocks of the spawner for it to be active. It will spawn mobs in an 8x8 square around itself. Obviously the spawner block cannot be centered in an 8x8 space, the first step of my album demonstrates how to find the 8x8 spawning area.

Very nice tutorial. Simple and to the point.

 

[nicktonton]

This is what I modeled up... The white square on the right is exactly 16 blocks from the "spawner" and you stand on a wood block in from of it so you are eye level with the spawner and 15 blocks away.
http://imgur.com/xMa7i

I would recommend moving the white square closer to the spawner, but still outside of the spawn radius. It looks to me like you could easily compress the design of the water-vater so that the white wool block is only 14 to 12 blocks from the spawner. I would keep the standing area outside of the spawn radius for obvious reasons, but within 16 blocks so you have a little extra area of space you can stand and still have the spawner spawn mobs, in case you don't place Steve in the exact square before going afk.

The drop is exactly 20.5 blocks, I have a halfslab for them to land on so they land 1.5 blocks higher then my feet pos. From what I have read the halfslab there ill prevent the archers from ever firing at you a single time.
http://imgur.com/cOZr4

I found the 1.5 block height above your feet to be the best easy way to prevent taking an arrow to the knee. However, I found when the drop was 20.5 blocks that the skeletons took two punches to kill, at a drop of 21.5 blocks the skeletons only take one punch. I'm thinking the best drop height for this design would be a 21.5 block fall.

The "inside" of the pool area will be 9x9x5 with the ceiling in place.
http://imgur.com/QHZkb

The design of the spawning room looks like it will work just fine to me.

This looks to be the "standard" xp farm as far as I can tell and from everyone's numbers. and I hope it doesn't look too bad

If you meant bad as in pretty, you shouldn't care. It's more than likely going to be hidden in a cave. In my opinion technical designs just need to be tidy and organized, which your design is very.

 

[KoncreteLiquids]

Moved the landing area 3 blocks closer so the white wool is at 13 blocks and you can stand at 12 or 13 blocks and hit the skeletons, also lowered it 1 block so the mobs fall 21.5. Now to kill some cows and research enchantment room layouts

Thank you very much Nicktonton, your the first person that helped with exact numbers... I like exact numbers on things like this

 

[KoncreteLiquids]

Do you happen to know the full "check to spawn" area? I read 17x17x9?

 

[nicktonton]

A mob spawner will spawn mobs in an 8x3x8 area around the spawner.

• Mobs will spawn on the same level (y dimenion) as the one the spawner block is on and on the level one space above and one space below the spawner block.
• They will spawn also within an 8x8 square around the spawner block. This 8x8 square is centered on the corner with the lower x and z coordinates.
  • An easy way to find the 8x8 is to use the debug menu to see co-ordinates and to move diagonally away from the spawner block in the direction where both the x and z numbers are getting lower, placing torches on the first four blocks in that direction. Place 3 torches in the opposite direction from the spawner and you will have marked off a diagonal for the 8x8 spawning area around the spawner.

If you go to the Imgur album I shared a few posts back, step one illustrates how to find the 8x8 square around the spawner block. Just ignore the last part of the step about digging the square block down two levels.

If this doesn't explain it for you, feel free to say so. I can't make videos, but I am willing to reword this info as much as needed.

Source: http://www.minecraftwiki.net/wiki/Monster_Spawner#Spawning_behavior and a video by Etho from Ethoslab. I will link the video in a bit, I just need to find it first. When I post the video you can watch it and see everything I've just said in video form.

 

[nicktonton]

This is a video that explains how to find a mob spawner's spawning area much better than what I said. You only need to watch the first minute and a half of it or so.

I couldn't find the link to the Ethoslab video I was talking about, I apologize, Etho was just who I learned it from.

 

[KoncreteLiquids]

I got the inside radius. From reading the wiki it seems that the monster spawner also checks a larger area for other "spawns" and not just players... The wiki mentions 17x17x9 but the date is a few years old...

I am asking so I know how far around my spawner I need to search for caves and spawns and light everything up so the spawner is the ONLY place.

When I made it, it is close to bedrock (y=18 I believe) so I dug every last piece of material out from under it all the way to bedrock, then built it back up to the spawner so I know there are no caves (or diamonds) below it... Now I want to clear around it so I can be assured that the only possible spawning place is inside the spawner.

Sorry if I didn't make that clear, I am still rather new so I may not be using the appropriate vernacular...


***Edit*** Hmm it seems like it read as being a much larger area then he explains... if what he says is how it is then I am more then good(by luck) when I built mine I cleared 4 extra blocks on all sides and the top and 17 blocks under it...

***Edit*** Went back and checked and I cleared a 25L x 17W x29D rectangle to make sure nothing was below the spawner, something like 12,000 to make sure I didn't leave and minerals or diamonds under it lol... So it appears I have plenty of clearance from the spawner

 

[nicktonton]

Mobs can spawn within 15x15 or 17x17 chunks around the player (I couldn't tell), however mobs outside of 128 blocks from the player will immediately despawn so you really only need to light up an area of 128 blocks in each direction around where you will stand while waiting for the mobs to spawn.

 

[KoncreteLiquids]

Yeah... not clearing 257x257... That is a little more then I am up for lol...

 

[nicktonton]

If you're going to go afk while the mobs are being spawned, it doesn't really matter, just come back on and kill the skeletons every 10 to 15 minutes.

 

[KoncreteLiquids]

Thank you again for your help... I feel like I can say now that I understand mob spawner's

 

[ScottWears]

Well .. this is a slice of awesome I think I will sticky it so others can see

 

[sciguyryan]

Mobs can spawn within 15x15 or 17x17 chunks around the player (I couldn't tell), however mobs outside of 128 blocks from the player will immediately despawn so you really only need to light up an area of 128 blocks in each direction around where you will stand while waiting for the mobs to spawn.

That is not completely accurate. Any mobs that have picked up an item will not despawn, ever. Its a new thing in 1.4.

Also. Slimes are a real issue for mob traps and lighting up caves will not fix it. If any of your caves intersect a slime chunk you will need to fill or slab those areas in order to make them spawn unfriendly.

The lighting up thing is only relevant for a dark room type spawner and not the type that involves a spawner cage. The lighting up surrounding areas and caves has no impact on them whatsoever.

 

[KoncreteLiquids]

The lighting up thing is only relevant for a dark room type spawner and not the type that involves a spawner cage. The lighting up surrounding areas and caves has no impact on them whatsoever.

This is not completely accurate, the spawner checks the local area for spawns of the same type... In this case I was dealing with a archer spawner and if a random archer walks inside of the radius that is one less the spawner can spawn...

Reminds me of the woodchuck nursery ryhme...

"How much spawn can a spawner spawn if a spawner could spawn spawn?"

ScottWears Thank you for making this a sticky, I literally spent hours on google trying to find some basic info the Nicktonton was able to hook me up with. If needed I can post other "basic's" threads like this as I learn my way through minecraft. for instance, I just (last night) went into the nether for the first time long enough to get everything needed for a blast furnace... That was some scary stuff, took me 3 trips...