Promethium Line · Refinery Tower with Swappable Flak / Autocannon / Mortar · 28–32 mm Grimdark Wargaming Terrain

### The Lookout

E-05 "The Lookout" is the intact refinery tower of the Promethium Line and one of the set's three large objectives. An octagonal refinery core with twin vents carries a wide observation gallery at 6″ and a platform at 3″, reached by two ladder runs. On the crown, a turret ring turns on a pivot pin and holds one of three swappable weapon heads on a keyed magnetic socket: a quad flak gun, a heavy twin autocannon or a siege mortar. You roll for the head before each game.

### Features

- Square base 292.1 × 292.1 mm (11.5″), terrain area 853.22 cm². All upper levels belong to it.
- Gallery 280 × 280 mm at 152.4 mm = 6″: 10 × 40 mm bases fit at the same time without overhang (561.94 cm² usable after core, ladder opening and cross path)
- Platform at 76.2 mm = 3″, 56 mm clear. Ladders 51.2 mm clear, 8 mm rung pitch.
- 24 mm armoured parapets with vision slits at all four gallery corners, mid-side left and right, and on both 3″ platform rails
- Three weapon heads on one socket, held by magnets and keyed by an arrow so they only seat one way. Traverse: flak 360°, autocannon 260°, mortar 360°.
- Top of the flak barrels 269.0 mm above the table
- A 262 × 50 mm cross path stays free on the gallery, and a 50 × 50 mm passage runs in front of the core at ground level
- Red shut-off valve with handwheel on the inlet, two promethium drums at an oil pool, OBJECTIVE plate on the crown
- System flange Ø 44 mm at 89.2 mm, flush with the plate edge
- Permanently glued build. The turret ring and the heads lift off for transport.

### Game use

Rules for Warhammer 40,000, 11th edition. Unofficial fan-made terrain. Not affiliated with or endorsed by Games Workshop. Warhammer 40,000 is a trademark of Games Workshop Ltd.

- Category: Dense (suggested, agree before the game), because of the closed refinery core.
- Levels: 3″ platform, 6″ gallery.
- Objective piece: yes. On a mission objective point, the whole area including both levels is the terrain objective.
- Weapon head: before deployment, after the terrain is set up, roll one D6 for each tower in view of both players. 1–2 Flak (special target: units that can FLY), 3–4 Autocannon (special target: VEHICLE or MONSTER units), 5–6 Mortar (special target: units of 6 or more models). The head stays all game. If nobody rolls, fit the flak.
- Terrain actions: at the start of your Shooting phase, one unit with a model on the 6″ gallery can give up its shooting and charge for the turn to pick one (measure from that model):
- FIRE CONTROL: pick one other friendly unit within 6″. Until the end of the phase, it re-rolls hit rolls of 1 for its ranged attacks.
- TOWER GUN: pick one enemy unit within 24″ that is visible to that model. Roll 1 D6, or 2 D6 if it is the head's special target. Each 4+ is 1 mortal wound. That averages 0.5 mortal wounds, or 1.0 against the special target. The mortar needs line of sight too.
- Set-wide frame: terrain actions are optional. Each player can start 1 terrain action per battle round, across all modules and copies. Effects do not stack.

### Print settings

- PETG, 0.4 mm nozzle, 0.2 mm layers
- 3 perimeters, 4 bottom / 5 top layers, 15 % gyroid, 240 °C nozzle / 80 °C bed
- No supports, no brim. Every part fits a 220 × 220 mm bed and is already in print orientation.
- The flak and autocannon barrels stand as slim columns up to 55 and 77 mm tall. Print them slowly (minimum layer time) and keep the fan on.
- 67 printed parts on 9 plates (01–09), plus the flange coupon (plate T)

Print time and filament (PrusaSlicer 2.9.6 estimate, heat-up not included):

- T · Flange coupon, print first: 0 h 28 min · 4 g
- 01 · Base quarter, railing, inlet, turret ring, all three weapon mounts, twin autocannon: 12 h 41 min · 147 g
- 02 · Base quarter, railings, core sleeves, name plate, console: 8 h 38 min · 111 g
- 03 · Base quarter, railing, valve handwheel: 6 h 27 min · 84 g
- 04 · Base quarter, railings: 6 h 09 min · 82 g
- 05 · Gallery quarter, upper ladder, platform railing: 5 h 56 min · 70 g
- 06 · Gallery quarter, lower ladder, platform railing: 5 h 53 min · 69 g
- 07 · Gallery quarter, pipe trestle, gallery beam, objective plate: 6 h 36 min · 78 g
- 08 · Gallery quarter, gallery beams, platform bracket: 6 h 59 min · 84 g
- 09 · Core, crown, 4 columns, platform, flak guns, mortar tube, chimneys, drums: 34 h 31 min · 401 g
- Total terrain: 93 h 51 min · 1,126 g (with coupon: 94 h 18 min · 1,130 g)

### What else you need

- 10 magnets, 5 × 2 mm discs: 2 for the pipe flange, 2 for the turret ring, 2 for each of the three heads (plus 4 if you fit them in the coupon)
- PETG-compatible glue. No ballast needed.

### Assembly highlights

- Print the coupon first and check the system pin and magnet fit on your own PETG.
- The base and the gallery each come in four quarters. Keys and beams underneath lock the seams. Glue them on a flat surface.
- The core stacks in three sections joined by sleeves. Four columns stand on printed pins and carry the gallery.
- Do not glue the turret ring. It turns on the pivot pin and lifts off for transport.
- Head magnets: ring seen from above with the arrow pointing away from you, left pocket north pole up, right pocket south pole up. The easy way: once the ring magnets have cured, let a loose magnet snap onto each ring magnet, put a drop of glue into the head's pocket and lower the head onto the ring. The head's magnets then end up the right way round.
- Flange magnet polarity, the same on every flange of the set: look at the flange face with the notch at the top. Left magnet north pole out, right magnet south pole out.
- Step-by-step instructions with all parts and positions are in BUILD_GUIDE_E.pdf.

### Works with the rest of the set

Promethium Line is a coherent terrain set in ten modules with one story. The mountain is the promethium source, drill station D taps it, and the pipeline H carries it past pipe bridge A and buffer tank B to the refinery with tower E and the bombed tower turned drill rig F. Loading yard G closes the chain. Craters K, the tanker wreck C and field defences J show the fight for it.

Every pipe flange in the set fits every other flange: Ø 44 mm, a square system pin and two 5 × 2 mm magnets. E sits on the 89.2 mm high line with A, B, D and F, and the riser H12 links it to the pipeline. Drill rig F is its bombed twin on the same footprint. E, drill station D and the vehicle crossing H14 make the three-central-objectives set-up described in the collection. See the Promethium Line collection for all modules.

### Files

- Model files: all single STLs in print orientation, plus one PrusaSlicer 3MF project per print plate, named job_<plate>_….3mf (T, 01–09). There is no G-code. Slice the 3MF projects with your own printer profile.
- Other files:
- rules_card_E.pdf: the module's rules card, 85 × 54 mm, a loose card
- E_WEAPONS_card.pdf: the weapon-head roll and the TOWER GUN action on one card
- TABLE_RULES_card.pdf: one card for the whole table (Core Rules reminder, objectives, terrain actions), two sides
- BUILD_GUIDE_E.pdf: parts list, plates, magnet polarity for flange and heads, step-by-step assembly
- RULES.pdf: all set rules in full, with Core Rules references and the balance maths
- source_E.zip: the parametric source code, to change tolerances and rebuild every STL
- Print all cards at 100 % (no page scaling). The Table Rules card has two pages: cut them out and glue them back to back.

### How it was made

Designed with AI assistance as parametric Python CAD code (build123d / manifold3d) and checked by automated tests: watertight meshes, overhangs of at most 45°, bridge lengths, collision checks of the full assembly, a placement test with ten 40 mm bases on the gallery, head seat, key play and traverse, and a PrusaSlicer run for every plate. It has not been test-printed yet. The fits and the magnet hold are designed, not proven on a real printer, so print the flange coupon first. Makes and feedback are very welcome.