Blast Furnace: money-making guide
The Blast Furnace makes bars with half the usual coal. Your profit comes from the gap between ore prices and the bars you sell, so a higher-level bar is not automatically the best choice. Check the margins before buying a stack.
Updated
Get to Keldagrim and fund the furnace
For your first visit, enter the cave east of Rellekka and take the dwarven boat to Keldagrim, starting The Giant Dwarf. You do not need to finish the quest. The Blast Furnace is in the eastern part of the city. Once you have visited, the Blast Furnace teleport in the Grouping menu is the convenient return; the Grand Exchange minecart is another route into Keldagrim.
Choose a Blast Furnace-themed world from the world list. Dwarven workers operate the machinery there for 72,000 coins per hour while you are using the service. Put coins in the coffer before starting. Below 60 Smithing, also pay the foreman 2,500 coins for each ten minutes of access. The calculator uses that standard fee; an activated ring of charos can reduce the foreman payment.
You can smelt iron at 15, steel at 30, mithril at 50, adamantite at 70 and runite at 85. Iron ore always becomes a bar here, which makes it worth checking even after you unlock steel. Gold is usually a training expense rather than a money maker; use the Smithing guide if fast XP is your priority.
Bring the equipment that keeps the loop moving
Wear ice gloves so you can take bars straight from the dispenser. Smiths gloves (i) work too. Without cooling gloves you need to cool the bars with water, adding another step; get the gloves before settling in for a long session.
For bars that need coal, bring a coal bag from the Motherlode Mine reward shop. Fill it from the bank, empty it beside the conveyor and send that coal into the furnace. It saves inventory trips but does not change the recipe. Wear weight-reducing equipment in the other slots and bring stamina potions.
Put ore, coal and stamina potions next to each other in a bank tab. Keep your coal bag in the same inventory slot so filling and emptying it becomes part of the rhythm. Set bank withdrawal to the ore quantity you use per trip.
Clicks and client settings
Make the furnace loop easier to read
These RuneLite plugins are included with the client. Find them in the plugin configuration sidebar, turn them on and open their settings.
Blast Furnace: keep the next lap ready
Enable Blast Furnace. Turn on Show conveyor belt clickbox and Show bar dispenser clickbox to make the two repeated clicks easier to place. Show coffer time remaining helps you top up before the workers stop. Check its stored-bar display when a batch seems stuck, then check the furnace’s ore and coal quantities before depositing more.
Build a coal buffer, then repeat the lap
Each steel bar needs one coal; mithril needs two, adamantite three and runite four. Iron needs none. Put coal into the furnace before sending the first ore batch. The interface shows your stored supplies: watch the coal count instead of assuming every full coal bag covers a full inventory of high-level ore.
- At the bank, fill the coal bag and withdraw ore. Run to the conveyor, deposit the ore, empty the bag and deposit its coal.
- Take the finished bars from the dispenser with cooling gloves equipped. Return to the chest and deposit the bars.
- Refill the bag and repeat. Add coal-only trips when your stored coal is running low, particularly for adamantite and runite. A batch that does not smelt usually means you have run out of coal or still need to clear the dispenser.
- Drink stamina as needed and keep enough coins in the coffer. Include coal-only trips, potion use and banking in your measured bars per hour.
Compare bars after the running costs
Select a bar below to compare the profit after supplies and fees. The starting pace assumes ice gloves and a coal bag for bars that need coal, with a 10% allowance below an efficient solo hour. While learning, time a session that includes coal runs and refuelling. Divide the bars banked by the minutes played and multiply by 60 to enter your bars per hour.
The result deducts ore, coal, workers, the standard foreman fee below 60, stamina and GE tax. Enter any other session costs separately. Buying a few ores and selling a few bars tests the margin before you commit your cash to thousands.
Compare other bars at current prices
Each bar uses its own starting pace and your level, stamina and other costs. Your custom pace applies only to the selected result above. Edited item prices are included.
Uses average instant-buy prices for supplies and instant-sell prices for loot, after GE tax. Edit a price to use your own offer.
When another bar is the better buy
Iron and steel can beat a high-level bar when their input margin is better or their faster banking loop makes up the difference. Runite ore also ties up much more cash. Compare a whole hour after expenses, then choose the recipe you can comfortably fund.
For an Iron, the Blast Furnace is a way to turn banked ore into useful bars while saving coal. Keep those bars for equipment, ammunition or Giants’ Foundry as needed. For faster Smithing levels on a main, compare gold smelting and Foundry before buying a large batch.