The crowning glory of an Andalusian reja is its decorative cresting (copete) and side consoles. Crafted using repoussé sheet hammering and scroll-horn forging, artisans create three-dimensional acanthus leaves, floral rosettes, and parabolic spiral volutes that soften the architectural severity of the iron security bars.
At a Glance: Key Takeaways
- Repoussé Sheet Chasing: Hammering 1.5mm to 2.5mm iron sheet over pitch bowls to create deep 3D sculptural relief.
- Horn Anvil Scroll Forging: Forming logarithmic spiral volutes (volutas) over the rounded bick of the blacksmith anvil.
- Collar Clip Joinery (Abrazaderas): Forged wrap-around iron bands binding adjacent scroll volutes together without welding.
- Split-Scroll Terminals (Colas de pez): Fishtail scroll ends forged with beveled chisel indentations.
- Baroque S-Curve Brackets: S-shaped cantilevered consoles supporting the lower shelf of the window cage.
1. Repoussé & Chasing: Sculpting Iron Sheet in Relief
The upper frieze (copete) of an Andalusian reja is adorned with flowing classical acanthus foliage. This ornament is not cast; it is hand-hammered from 1.5mm to 2.5mm wrought iron or low-carbon steel sheet using the ancient techniques of repoussé (hammering from the reverse to create volume) and chasing (chiseling from the front to define fine surface veining).
The artisan supports the heated sheet over an anvil or a leather pitch-bowl filled with a malleable blend of pine rosin, tallow, and brick dust. Using curved ball-punches and repoussé hammers, the smith raises bold lobes and undulating leaf borders. The fine leaf veins and serrated margins are then cut from the face using curved chasing chisels (cinceles), giving the heavy metal the organic, weightless vitality of living foliage.
2. Forging the Perfect Spiral Volute (La Voluta)
The side consoles, crest flanks, and lower shelf corbels are composed of sweeping spiral volutes. A poorly forged scroll looks stiff and mechanical; a master-forged volute follows the logarithmic curvature of the Golden Ratio ($$\Phi \approx 1.618$$).
The blacksmith begins by tapering the end of a square bar, flattening it into a beveled fishtail (cola de pez). The initial scroll button is turned over the anvil edge with quick hammer blows. The expanding spiral curve is then rolled progressively over the rounded bick (horn) of the anvil or around a specialized bending scroll jig (grifa), ensuring that the gap between adjacent coils widens in continuous, fluid proportion.
3. Collar Clip Joinery (Abrazaderas)
Where multiple forged scrolls meet back-to-back, master smiths join them using abrazaderas (collar clips). An abrazadera is a narrow band of ductile flat iron (typically 20mm × 4mm) that wraps completely around the touching scrolls.
The collar is heated bright red in the forge, clamped across the scroll junction with specialized tongs, and hammered tightly around all four faces. As the collar cools, it contracts forcefully, locking the scrolls into a rigid, self-supporting ornamental truss that withstands centuries of storm winds without loosening.
Ornamental Forging Techniques for Reja Crestings
Use this reference table to calculate exact physical dimensions, ratios, and specifications before purchasing:
| Ornamental Element | Forging Technique | Material Stock | Architectural Role |
|---|---|---|---|
| Acanthus Leaf Foliage | Hot repoussé and chasing over pitch | 1.8mm sheet iron plate | Upper copete cresting, central heraldic shields |
| Logarithmic Volute | Scroll horn bending over anvil bick | 16mm × 8mm flat bar or 16mm square | Side consoles, pediment brackets, apron corbels |
| Fishtail Terminal (Cola de Pez) | Bevel tapering and flat spreading | Solid bar end | Decorative terminal button of all spiral scrolls |
| Collar Clip (Abrazadera) | Hot wrapping and swaging | 20mm × 4mm flat bar | Binds adjacent scrolls together without welds |
Aesthetic & Structural Constraints
Every successful decoration project must account for physical and environmental constraints:
Proportional Balance
The upper cresting must not exceed 25% to 30% of the total reja height, or the window appears top-heavy.
Weight Cantilever
Heavy repoussé crests shift the center of gravity outward; upper wall mounting brackets must be deepened accordingly.
Protocol for Forging a Traditional Scroll Volute with Collar
Execute this professional sequence to achieve flawless results without backtracking:
Bar Tapering & Fishtail Forging
Heat bar end to 1,000°C; forge a smooth taper, spreading the tip into a flared fishtail with a cross-peen hammer.
Scroll Button Turning
Hook the fishtail tip over the far edge of the anvil; tap with light hammer blows to initiate the tight inner scroll button.
Anvil Bick Rolling
Heat the forward third of the bar; roll the curve progressively across the tapered anvil horn to expand the spiral.
Scroll Jig Tuning
Check curvature against full-scale chalk drawings; adjust tight curves using handheld bending forks (grifas).
Hot Collar Fabrication (Abrazadera)
Forge a U-shaped iron collar; heat to bright red and slip over the touching scroll bars on the assembly bench.
Collar Swaging & Shrink Fit
Hammer the collar ends closed around the scrolls with a swage tool; allow thermal cooling shrinkage to clamp the joint solid.
Common Mistakes & Countermeasures
Avoid these costly errors that compromise aesthetics, ergonomics, and budget:
Using flat cold-rolled sheet steel cut with a plasma cutter for acanthus leaves
Tack-welding scroll intersections on the rear face instead of using collars
Project Execution Checklist
Track your physical progress. Checkboxes persist automatically on this device:
Frequently Asked Questions
How did blacksmiths create identical left and right scroll volutes for symmetrical crests?
Smiths forged a single master scroll, hardened it in water, and used it as a bending template (schablone). Hot bars were clamped to the master template and bent around it, ensuring left and right scrolls matched to within 1mm.
What tools are used for chasing iron sheet?
Blacksmiths use chasing hammers (with broad, slightly convex faces) and dozens of specialized steel chisels (cinceles): linear liners for veins, curved punches for contours, and textured matting tools to create matte background shading.
