package net.mcft.copy.betterstorage.item.cardboard;

import net.mcft.copy.betterstorage.content.Items;
import net.mcft.copy.betterstorage.item.ItemBetterStorage;
import net.minecraft.item.EnumArmorMaterial;
import net.minecraft.item.EnumToolMaterial;
import net.minecraftforge.common.EnumHelper;

public class ItemCardboardSheet extends ItemBetterStorage {

	public static final EnumToolMaterial toolMaterial =
			EnumHelper.addToolMaterial("cardboard", 0, 48, 2.5F, 0.0F, 18);
	public static final EnumArmorMaterial armorMaterial =
			EnumHelper.addArmorMaterial("cardboard", 3, new int[]{ 1, 2, 2, 1 }, 20);
	
	public ItemCardboardSheet(int id) {
		super(id);
		setMaxStackSize(8);
		
		toolMaterial.customCraftingMaterial = this;
		armorMaterial.customCraftingMaterial = this;
	}
	
}

package net.mcft.copy.betterstorage.item.cardboard;

import net.mcft.copy.betterstorage.content.Items;
import net.mcft.copy.betterstorage.item.ItemBetterStorage;
import net.minecraft.item.EnumArmorMaterial;
import net.minecraft.item.EnumToolMaterial;
import net.minecraftforge.common.EnumHelper;

public class ItemCardboardSheet extends ItemBetterStorage {

	public static final EnumToolMaterial toolMaterial =
			EnumHelper.addToolMaterial("cardboard", 0, 48, 2.5F, 0.0F, 18);
	public static final EnumArmorMaterial armorMaterial =
			EnumHelper.addArmorMaterial("cardboard", 3, new int[]{ 1, 2, 2, 1 }, 20);
	
	static {
		toolMaterial.customCraftingMaterial = Items.cardboardSheet;
		armorMaterial.customCraftingMaterial = Items.cardboardSheet;
	}
	
	public ItemCardboardSheet(int id) {
		super(id);
		setMaxStackSize(8);
	}
	
}

--- 
+++ 
@@ -13,14 +13,12 @@
 	public static final EnumArmorMaterial armorMaterial =
 			EnumHelper.addArmorMaterial("cardboard", 3, new int[]{ 1, 2, 2, 1 }, 20);
 	
-	static {
-		toolMaterial.customCraftingMaterial = Items.cardboardSheet;
-		armorMaterial.customCraftingMaterial = Items.cardboardSheet;
-	}
-	
 	public ItemCardboardSheet(int id) {
 		super(id);
 		setMaxStackSize(8);
+		
+		toolMaterial.customCraftingMaterial = this;
+		armorMaterial.customCraftingMaterial = this;
 	}
 	
 }
Fix cardboard items being unrepairable
