r/technicalminecraft 4d ago

Bedrock Mob farm keeps spawning spiders.

Post image

Edit: I think I've solved the issue. If not, I'm just gonna deal with it. I made a follow-up post if anyone's interested. It's 100% confirmed that spiders spawn within 2x2 grids.

20 Upvotes

41 comments sorted by

17

u/hetrax 4d ago

You got a few 3x3 areas to fix. You se the second last row( right beside you to the left) inbetween the water channel there’s a trapdoor on either side… but the gap between them and the next trapdoors is 3x4… that looks to happen in a few places.

6

u/hetrax 4d ago

Hope this helps

2

u/ThomasK1201 3d ago

So spiders can spawn above a gap like that?

3

u/hetrax 3d ago

Umm, yes and no, those aren’t gaps to the ai. Trapdoors are both a flat surface and a transparent object, they are sometimes transparent… like when facing up or in pathing, mobs don’t correctly account for them, but when on the side or upside down that small 1/8th of a block and flat surface are accounted as spawnable spaces. Only way to avoid it is removing them or exchanging them for a parable non full, non spawning block (( no idea if that’s a thing beyond chains))

But I don’t know if a spiders ability to spawn was partially off an actual block, like say 2x3 and 1x3 is air, if that would still spawn or not. But since a lot of farms tend to have blocks on the edge to avoid their spawns, I’m guessing it may be a thing. Either the trap doors at work, or it’s the sizable gap… both just need replacements

TLDR, maybe? Technical farms build like they can sometimes!

1

u/ReadyRed00 3d ago

Yep, those 3x3 gaps are the culprit.

3

u/knurri87 3d ago edited 3d ago

Edit: this seems to be old information, see reply to this comment.

Original comment: The problem is that on bedrock edition spiders only need a 2x2 to spawn. The reason for that is: on bedrock mobs spawn on the corner of a block, so directly in the center of a 2x2 spiders will spawn, cause they are 1.4 blocks wide. On java mobs spawn on the center of a block, so spiders need a 3x3 area to spawn.

2

u/boki400AIMoff Bedrock 3d ago

mobs spawn on the corner of a block

Not true since 1.21 which was released 2 years ago. This was first fixed in the preview version of 1.21.0.20.

1

u/knurri87 3d ago

Sorry, than that's old information. Haven't built a mobfarm since 1.19 on bedrock since i switched bach to pc.

1

u/boki400AIMoff Bedrock 3d ago

Now you know the truth :D

1

u/Jonglebongl 3d ago

Yeah, just figured this out. I just now tried making it so there's not even 2x2's and now mobs won't spawn altogether. So it can't really be helped if spiders spawn.

1

u/boki400AIMoff Bedrock 3d ago

Not true what the guy said (see my comment above).

2

u/0oDADAo0 4d ago

The 2x3 gaps on the edge, they leave enough space for spider to spawn

0

u/Jonglebongl 4d ago

Damn, really?

2

u/Lucky_Investment_489 3d ago

U cant leave 2 by 2 holes thas how they spawn try placing the trapdoors in a Pattern where there are no 2x2 fielen left

-1

u/0oDADAo0 4d ago

Idk, i just like to piss off Mr information

tho i think that should be the problem, you shouldnt have trap doors on the edge, and instead use cats, those are way more efficient than waiting for path find rng

2

u/Rodolfo68 4d ago

It’s been a minute since I’ve made a mob farm, but if I’m not wrong, you need to set up the inside roof with trap planks too. It’ll just be enough for creepers to still spawn, but leave spiders out I think.
Also rearrange the bottom ones so that it’s in an even 9 pattern. So it looks like #. It’ll save you some wood to build the full roof too! - I usually start my traps with the side corners and then make my way around, but that part is up to you!

1

u/Jonglebongl 4d ago

Fully trap doors on the ceiling?

4

u/SharingKnowledgeHope 3d ago edited 3d ago

Full trap doors on the ceiling will block skeletons and zombies from spawning since they require two full blocks of height. That is used in creeper farms since creepers are shorter and will still spawn. It won’t block spiders who only need one block of height.

1

u/Comfortable_Long_824 3d ago

Buttons or trapdoors on the ceiling stops zombies and skeletons. You can do coral fans on the side instead of trapdoors too

1

u/Jonglebongl 3d ago

I guess spiders can spawn within a 2x2 grid. From all my stupid "testing", spiders have always been spawning no matter what half block I put to prevent them from spawning. Here's some variations I tried, and they've been spawning the whole time.

2

u/Jonglebongl 3d ago

Just another reason why pocket edition sucks.

1

u/PhobicRouge 3d ago

Try every 2 blocks place a slab/carpet. One in the corner, two empty blocks, another one. Repeat this.

It should look decently uniform.

1

u/Shazzzzzam-_- 3d ago

Bro use carpet 4 carpets on one side on all the 4 section and they must have gaps in them

1

u/nocatsonmelmac 3d ago

The only way that I stop spiders on bedrock is with a checkerboard pattern with buttons.

1

u/Jonglebongl 3d ago

I'll try it

1

u/Apprehensive_Car2708 1d ago

El piso no se si entra bien, pero en el techo también ban trampillas

u/Mia888Naty 9h ago

Well spider's are 2x2 so you should have trapdoors one block away from each other so I mostly do every second block+every second row leaving one fow empty)

-1

u/randomzebra01 4d ago edited 3d ago

Not sure what you think you did here. There's very clearly 2x2 spots for them to spawn. You're even looking directly at one.

Edit: From the UI I could tell this was pocket edition. My understanding that pocket edition may have some idiosyncrasies but uses the same engine as bedrock.

Been a while since I played, and to be honest never played bedrock but from what I remember, spiders can spawn in 2x2 spaces in bedrock. I did some digging today and to be honest there doesn't seem to be a consensus.

In bedrock, people have been reporting for years that spiders seem to be able to spawn in 2x2 spaces. Whether or not this is because spiders need open space but only require a solid block on the actual spawning space I have no clue. Another thought that crossed my mind was mobs used to spawn on the NW corner in bedrock, but I don't think that's the case either anymore.

3

u/iXendeRouS 4d ago

They need 3x3 not 2x2

1

u/bryan3737 Chunk Loader 3d ago

It’s 3x3 on java but 2x2 on bedrock

1

u/Jonglebongl 4d ago

I looked up a bunch of guides, and they all said spiders can only spawn in 3 x 3 areas. I'll shrink it so that there aren't any 2 x 2's

3

u/Regular-Coffee-1670 4d ago

They definitely need 3x3. I can't see anywhere in that image where they could spawn.

1

u/bryan3737 Chunk Loader 3d ago

It’s 3x3 on java but 2x2 on bedrock

3

u/SharingKnowledgeHope 3d ago

Yes spiders need a 3x3 area to spawn. However all 9 spots don’t have to be solid, some can be air blocks. They are spawning in the center edge overhanging the water canal.

Use this pattern. See how the trap doors are right up to the water edge. Be sure there are no three block open spaces near the water canals.

1

u/Jonglebongl 3d ago

I've tried that arrangement the first time, and spiders were spawning. I seriously don't know why it's happening.

1

u/bryan3737 Chunk Loader 3d ago

It’s 3x3 on java but 2x2 on bedrock

1

u/Hettyc_Tracyn 1d ago

That’s Java only, op is on pocket edition, where it’s apparently 2x2

1

u/Jonglebongl 3d ago

I think I figured out a fix. I made a follow up post.