Welding Fails When Player or Grid Inventory Is Full (Invisible Staging Buffer Issue)

ame: Space Engineers 2

Mode: Survival

Reproducible: Yes (intermittent but consistent under certain conditions)

Summary:

Welding stops functioning when either the player inventory or the grid inventory is full. The welder produces sparks but does not apply components or progress the block. Dropping ore or freeing inventory space immediately restores welding functionality. This behavior is not documented and did not occur in earlier builds.

Steps to Reproduce:

Fill the player’s backpack to maximum capacity (especially with silicon or mixed ores).

Fill the grid’s cargo containers or approach near‑full capacity.

Attempt to weld any block using the hand welder or area welder.

Observe that sparks appear, but no welding progress occurs.

Drop any ore (iron works reliably) to free one inventory slot.

Attempt welding again — welding now works normally.

Expected Behavior:

Welding should apply components directly to the block even when inventory is full, or the game should provide a warning message explaining that welding requires free inventory space.

Actual Behavior:

Welding silently fails with no error message. Sparks appear, but no components are applied and no progress is made. Freeing inventory space immediately resolves the issue.

Additional Notes:

Issue appears related to the welder’s internal “staging buffer” failing when inventory is full.

Silicon ore seems more likely to trigger the issue, possibly due to stacking behavior.

The issue can also occur after switching welders or carrying both welders, but inventory fullness appears to be the root cause.

Reloading the save also resolves the issue temporarily.

System:

Survival, single‑player, standard settings.