Fix issue restricting the maximum size of contraptions.

src/main/java/com/simibubi/create/content/contraptions/components/structureMovement/Contraption.java

@@ -21,6 +21,7 @@ import java.util.stream.Collectors;
 
 import javax.annotation.Nullable;
 
+import com.simibubi.create.foundation.utility.*;
 import org.apache.commons.lang3.tuple.MutablePair;
 import org.apache.commons.lang3.tuple.Pair;
 
@@ -53,11 +54,6 @@ import com.simibubi.create.content.logistics.block.redstone.RedstoneContactBlock
 import com.simibubi.create.foundation.config.AllConfigs;
 import com.simibubi.create.foundation.fluid.CombinedTankWrapper;
 import com.simibubi.create.foundation.render.backend.light.EmptyLighter;
-import com.simibubi.create.foundation.utility.BlockFace;
-import com.simibubi.create.foundation.utility.Iterate;
-import com.simibubi.create.foundation.utility.NBTHelper;
-import com.simibubi.create.foundation.utility.NBTProcessors;
-import com.simibubi.create.foundation.utility.VecHelper;
 import com.simibubi.create.foundation.utility.worldWrappers.WrappedWorld;
 
 import net.minecraft.block.AbstractButtonBlock;
@@ -178,7 +174,7 @@ public abstract class Contraption {
 
 	public boolean searchMovedStructure(World world, BlockPos pos, @Nullable Direction forcedDirection) throws AssemblyException {
 		initialPassengers.clear();
-		Queue<BlockPos> frontier = new LinkedList<>();
+		Queue<BlockPos> frontier = new UniqueLinkedList<>();
 		Set<BlockPos> visited = new HashSet<>();
 		anchor = pos;
 

src/main/java/com/simibubi/create/foundation/utility/UniqueLinkedList.java

@@ -0,0 +1,89 @@
+package com.simibubi.create.foundation.utility;
+
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.stream.Collectors;
+
+public class UniqueLinkedList<E> extends LinkedList<E> {
+    private final HashSet<E> contained = new HashSet<>();
+
+    @Override
+    public boolean contains(Object o) {
+        return contained.contains(o);
+    }
+
+    @Override
+    public E poll() {
+        E e = super.poll();
+        contained.remove(e);
+        return e;
+    }
+
+    @Override
+    public boolean add(E e) {
+        if (contained.add(e)) return super.add(e);
+        else return false;
+    }
+
+    @Override
+    public void add(int index, E element) {
+        if (contained.add(element)) super.add(index, element);
+    }
+
+    @Override
+    public void addFirst(E e) {
+        if (contained.add(e)) super.addFirst(e);
+    }
+
+    @Override
+    public void addLast(E e) {
+        if (contained.add(e)) super.addLast(e);
+    }
+
+    @Override
+    public boolean addAll(Collection<? extends E> c) {
+        List<? extends E> filtered = c.stream().filter(it -> !contained.contains(it)).collect(Collectors.toList());
+        return super.addAll(filtered);
+    }
+
+    @Override
+    public boolean addAll(int index, Collection<? extends E> c) {
+        List<? extends E> filtered = c.stream().filter(it -> !contained.contains(it)).collect(Collectors.toList());
+        return super.addAll(index, filtered);
+    }
+
+    @Override
+    public boolean remove(Object o) {
+        contained.remove(o);
+        return super.remove(o);
+    }
+
+    @Override
+    public E remove(int index) {
+        E e = super.remove(index);
+        contained.remove(e);
+        return e;
+    }
+
+    @Override
+    public E removeFirst() {
+        E e = super.removeFirst();
+        contained.remove(e);
+        return e;
+    }
+
+    @Override
+    public E removeLast() {
+        E e = super.removeLast();
+        contained.remove(e);
+        return e;
+    }
+
+    @Override
+    public void clear() {
+        super.clear();
+        contained.clear();
+    }
+}