Ashlands Geothermal Foundry — 0.2.8 prototype

Build an industrial foundry powered by natural Ashlands lava. Submerge a metal probe, snap conduits together, and smelt ore without coal.

0.2.8: Updates the release version and the package's short Thunderstore description. Gameplay, geometry, pipe alignment, storage and save data are unchanged from 0.2.7.

0.2.7: Corrects the pillar's sideways offset relative to the four lava connectors and extends their inner ends into the masonry. Snap endpoints remain unchanged. Restart Valheim after replacing the previous mod version. The geometry correction is awaiting an in-game visual retest.

Status: lava-powered smelting was confirmed in the 0.1.2 user playtest. This update adds revised materials, a stone/metal body, and separate storage; those changes still require an in-game playtest. This is a local development build, not a published Thunderstore release.

0.2.1 visual correction

Corrects the 100x scale regression introduced by the 0.2.0 static mesh conversion. Removes the additive glow submesh and the old furnace fire-effects hierarchy. All six pieces now receive icons rendered from their custom geometry. A dimension check rejects an incorrectly scaled furnace before its collider is created.

Restart with 0.2.1 and existing foundries should pick up the corrected geometry; dismantling is not required. The two-bin save format is unchanged. This correction compiles and passes managed checks, but its Unity rendering still needs an in-game retest.

0.2.2 front bins and pipe finishing

The front bins now meet at a narrow divider, with a shared plinth and backplate joining them to the furnace. Decorative marker colliders are removed, so both output markers target the OUTPUT bin beneath them. The furnace body no longer opens INPUT when clicked; storage access is through the two front bins.

The original blast-furnace pipes are retained. Eight exposed pipe rims receive fitted dark-metal end caps/collars. Obsolete loading-port mesh islands are removed and a solid rear fascia covers the former loading area. Heat-network sockets remain in their existing positions. Prefab IDs and storage data are unchanged.

0.2.3 connected original pipes

The original pipes now continue from their baked end-ring centres into the input/output housing, with aligned unions and elbow joints. A recessed solid metal backing closes the old loading openings and lower arch; square wall details and round heat sockets are retained. The bin plinth and backplate no longer share exposed coplanar faces with the bins. Pipe emission is reduced by 25%, both initially and during heat updates; global bloom settings are unchanged.

Restart to refresh existing pieces. Storage data and snap positions remain unchanged. Visual alignment and opening closure still require an in-game retest.

0.2.4 masonry and centered sockets

Removes the large internal metal block. The openings are rebuilt as stone faces in the pillar mesh, fitted to adjacent masonry at both heights to follow its taper. There are no separate cover blocks. Original pipes remain, with short individual connections into the bin backs instead of external crossing loops. The lava sockets and their snap points now use the measured stone pillar centre.

Existing pipe networks need to be re-snapped to the repositioned foundry sockets. Restart to update existing models. Both inventories retain the same save format. The 25% reduction in pipe emission remains.

0.2.5 bent ground returns

Reverts the stone repairs. The original loading openings receive fitted pipe adapters and smooth bent pipes descending below the base. The lower return is staggered outward and centred between the upper pair to avoid intersections. They glow red only when the connected lava network supplies heat; these visual returns do not replace the submerged lava probe.

The complete model and its bin connections are centred together on the construction grid. Connection ports use exact two-metre offsets and a common half-metre-aligned height so rotations remain consistent. Existing foundries update on restart, but connecting conduits need re-snapping to the revised sockets. Inventory data is unchanged.

0.2.7 rear adapters and connector clearance

The square opening receives a 1.04m by 1.05m solid adapter, and the round opening a 1.08m diameter solid flange. Both extend through the old rim depth, with the bent pipes starting inside the adapters. No stone patches or full-height cover block are added.

All four lava connectors and their snap points use exactly y=2.75m and two-metre cardinal offsets from the root. This clears the upper adapter by 23cm. An offline audit measured at least 30cm from connector cylinders (using a conservative collar radius) to sampled original pipe vertices. The three ground returns retain at least 6.6cm calculated clearance. These checks do not replace a native in-game visual inspection or check arbitrary neighboring builds.

Release build and 41 core/inventory checks pass. On restart, re-snap attached conduits to the final connector height. Verify the old port rims are fully obscured from front and side views, all connector endpoints share a plane, and the retained original pipes remain clear. Storage data and heat requirements are unchanged.

Included

• A custom geothermal foundry using modified vanilla blast-furnace geometry.
• A four-metre lava probe with four horizontal heat sockets.
• Two-metre straight and vertical conduits, a corner, and a six-way junction.
• Heat connections use coincident, opposing snap ports, with 12 cm tolerance. Nearby pieces without matching ports do not connect.
• One submerged probe powers four connected foundries at full speed. Eight foundries on one probe run at half speed. Additional probes restore capacity.
• Separate input and output inventories, each 80 slots by default, adjustable to 32–160 slots. Normal item stack sizes apply. The two front bins have distinct hover names: INPUT (one raised marker) and OUTPUT (two markers).
• A configurable 1,000-bar output limit. Smelting pauses when output is full, no inventory slot is available, either bin is open, or heat is lost.
• Ten seconds per bar at full heat by default. Ore is consumed one-for-one using the input/output mappings from the vanilla smelter and blast furnace.
• Ash/lava environmental damage immunity on these custom pieces. Normal structural support and combat damage remain.
• Native item serialization in a single versioned payload for both bins, saved recipe progress, and owner-only processing. A conversion is staged before either live inventory is changed.

Install the local build

1. Use a separate test profile and a disposable world for the first playtest.
2. Install BepInExPack Valheim and Jötunn. This build references Jötunn 2.30.0 and the Valheim assemblies installed on this machine on September 14, 2026.
3. In Thunderstore Mod Manager or r2modman, use Settings → Import local mod, select AshlandsGeothermalFoundry-0.2.8.zip, and enable it. If your manager does not offer local import, extract the ZIP and copy its plugins/AshlandsGeothermalFoundry directory into your selected profile's BepInEx/plugins directory.
4. Launch the modded game. All six build pieces should appear in the Hammer's native Crafting filter.

The package contains this mod only. It does not bundle game files, BepInEx, or Jötunn. Every multiplayer peer and the server need the same mod version and matching configuration; automatic configuration synchronization is not implemented in 0.2.0.

Updating from 0.1.x

Exit Valheim and replace the previous mod with 0.2.8 in the same test profile. Keep only one enabled copy of the DLL. Existing foundry IDs are unchanged. Their old shared hopper is read into INPUT, and finished bars are moved into OUTPUT on the owner's next processing tick. Any stack that cannot fit remains in INPUT.

The two-bin save format requires 0.2.0 or newer. Empty both inventories before reverting to an older version. After updating, check an existing foundry's item totals, then save/reload to verify both bins.

Build your first installation

1. Build a supported platform beside a natural Ashlands lava pool.
2. Place the probe so its four-metre shaft crosses the lava surface. The tip must reach the lava terrain surface and be no more than four metres below it. Dry ground and rods floating above lava do not supply heat. The hover text reports whether it is submerged.
3. Snap a straight conduit to a probe collar. Use corners and junctions to turn; a six-way junction joins horizontal and vertical runs.
4. Connect a foundry socket. Its four sockets are centred on the stone pillar, two metres out from its measured centre. Adjacent foundries can connect directly if their opposite sockets meet.
5. Open the front INPUT bin (one marker), insert ore, then close it. Production pauses while either bin is open.
6. Open the separate OUTPUT bin (two markers) to collect bars. Hover text reports network heat and processing speed.

Conduit ports sit one metre from each piece's centre, giving a two-metre repeating grid. A pair of opposing foundry sockets spaces foundry centres four metres apart. Actual model clearance still needs an in-game check.

Construction costs

Piece	Resources
Foundry	30 iron, 20 black metal, 40 stone, 10 surtling cores
Probe	10 iron, 5 black metal, 2 surtling cores
Each conduit	2 iron, 2 stone

All pieces require a workbench nearby to build. Recipes are prototype balance values.

Settings

After first launch: BepInEx/config/local.ashlands.geothermalfoundry.cfg.

Section / key	Default	Meaning
Foundry / HopperRows	10	Input rows, eight columns; restart after changing.
Foundry / OutputRows	10	Output rows, eight columns; restart after changing.
Foundry / OutputBarLimit	1000	Finished-bar count at which processing pauses.
Foundry / SecondsPerBar	10	Seconds per item with full heat.
Heat / FoundriesPerProbe	4	Full-speed capacity per submerged probe.

Prototype boundaries

• Heat chaining is implemented; automatic ore transfer between foundries is not.
• Both bins accept manual item storage; only ore in INPUT is processed. Bars are produced exclusively in OUTPUT. Other items placed in either bin occupy space normally.
• Production requires the network pieces to be loaded. There is no offline catch-up or processing in unloaded world areas.
• All connected foundries share heat, including idle ones.
• Ambient biome heat alone does not power the foundry. The optional ambient-heat bonus is not implemented.
• The foundry retains vanilla stone and metal, with wood and leather bellows removed. Procedural conduits use a darker crop of the vanilla furnace pipe material, with snow and vertex displacement disabled. Build-menu icons are rendered from each finished custom model.
• Other mods that replace container behavior, alter stack limits, or rewrite vanilla furnace recipes may need compatibility work.
• Empty and dismantle custom pieces before removing the mod from a world you intend to keep.

Build from source

Requires a .NET SDK with the .NET Standard 2.1 reference pack. The test runner targets .NET 10. No NuGet downloads are required.

Copy Environment.props.example to Environment.props, set the three local paths, then run:

./build.ps1

The script builds the DLL, runs the core tests, and creates the local-import ZIP in dist. It does not install into your game or modify saves. SDK scratch files remain in .build.

See TESTING.md for the verification record and the remaining playtest steps.

The implementation follows Jötunn's custom piece registration API, with game API signatures checked against the locally installed assemblies.