Sovereignty Module: Fuse the Steel
Complete Welding, Brazing, Soldering, and Metal Joining Guide
Joining metal to metal is the foundation of all machinery, vehicles, structures, and tools beyond the simplest forgework. This campaign covers every method from forge welding (requiring only fire and hammer) through electric arc welding, plus brazing, soldering, and riveting.
Chapter 1: Joining Methods Overview
| Method | Temperature | Filler Metal | Strength | Equipment Needed |
|---|---|---|---|---|
| Forge welding | 2,000-2,500F | None (base metal fuses) | Excellent | Forge, anvil, hammer |
| Arc welding (stick/SMAW) | 6,000-10,000F | Electrode rod | Excellent | Welder (DC generator or transformer), electrodes |
| Oxy-acetylene welding | 5,700F | Filler rod (same as base) | Excellent | Oxygen + acetylene tanks, torch |
| MIG welding | 6,000F+ | Wire feed | Excellent | MIG welder, shielding gas, wire |
| Brazing | 1,100-1,500F | Brass/bronze/silver alloy | Good | Torch or furnace, flux, filler |
| Soldering | 350-750F | Tin-lead or tin-silver | Low-moderate | Soldering iron or torch, flux |
| Riveting | Ambient (cold) or heated | Rivet (same or compatible metal) | Good | Hammer, bucking bar, drill |
| Bolting | Ambient | Bolt + nut | Good (removable) | Wrench, drill |
Chapter 2: Forge Welding
The oldest joining method. Two pieces of iron/steel heated to white heat (2,300-2,500F) and hammered together until they fuse into one piece.
| Step | Action | Critical Detail |
|---|---|---|
| 1 | Heat both pieces to bright yellow-white | Must be same temperature; too cool = no bond |
| 2 | Sprinkle flux (borax) on joint faces | Prevents oxide formation that blocks bonding |
| 3 | Place pieces together on anvil | Align quickly before cooling |
| 4 | Strike center first, work outward | Squeezes flux and oxide out of joint |
| 5 | Return to fire, reheat, hammer again | Multiple heats for full penetration |
| 6 | Inspect: joint should be invisible | Good weld shows no seam line |
Flux options: Borax (best), sand (adequate), iron filings + borax (for difficult steels).
Chapter 3: Arc Welding (SMAW/Stick)
| Parameter | Setting | Notes |
|---|---|---|
| Electrode diameter | 1/8" (3.2mm) general purpose | Larger for thicker metal |
| Current (amperage) | 80-130A for 1/8" rod | Higher = deeper penetration |
| Polarity | DCEP (electrode positive) for most rods | Some rods run AC |
| Arc length | Equal to electrode diameter | Too long = spatter; too short = sticking |
| Travel speed | Steady, consistent | Too fast = narrow/weak; too slow = excessive buildup |
| Electrode angle | 10-15 degrees tilt in travel direction | Drag technique |
Common electrodes: E6011 (all-position, AC/DC, dirty metal), E6013 (easy arc, thin metal), E7018 (strongest, low hydrogen, structural).
Chapter 4: Oxy-Acetylene Welding and Cutting
| Function | Flame Setting | Technique |
|---|---|---|
| Welding steel | Neutral (equal O2 and C2H2) | Heat base metal to puddle, add filler rod |
| Welding cast iron | Slightly carburizing (excess acetylene) | Preheat entire piece, slow cool |
| Brazing | Slightly oxidizing | Heat base metal, apply brass filler |
| Cutting steel | Neutral preheat, then oxygen blast | Preheat to cherry red, trigger cutting oxygen lever |
| Heating/bending | Large rosebud tip, neutral | Even heat distribution |
Flame types: Carburizing (feathery inner cone, excess fuel), Neutral (sharp inner cone, balanced), Oxidizing (small pointed cone, excess oxygen).
Chapter 5: Joint Types and Positions
| Joint Type | Description | Strength | Common Use |
|---|---|---|---|
| Butt joint | Two pieces edge-to-edge | High (if full penetration) | Plates, pipes |
| Lap joint | One piece overlaps another | Good | Sheet metal, patches |
| T-joint (fillet) | One piece perpendicular to another | Good | Structural connections |
| Corner joint | Two pieces meet at corner | Moderate-good | Boxes, frames |
| Edge joint | Two pieces parallel, welded at edges | Low | Sheet metal, thin material |
Welding positions: Flat (easiest), Horizontal, Vertical (up or down), Overhead (hardest). Practice flat first, master each position before moving to the next.
Chapter 6: Brazing and Soldering
| Parameter | Brazing | Soldering |
|---|---|---|
| Temperature | 1,100-1,500F | 350-750F |
| Filler metals | Brass, bronze, silver alloy | Tin-lead (60/40), tin-silver, tin-copper |
| Flux | Borax-based paste | Rosin (electronics), acid (plumbing) |
| Joint strength | 40,000-70,000 PSI | 5,000-10,000 PSI |
| Gap (ideal) | 0.001-0.005 inches | 0.001-0.005 inches |
| Best for | Dissimilar metals, thin sections, copper/brass | Electronics, copper plumbing, tin work |
Capillary action: Both brazing and soldering work by capillary action. The filler metal is drawn into a tight-fitting joint by surface tension. Proper fit-up (tight gap) is more important than adding more filler.
Chapter 7: Riveting
| Rivet Type | Material | Application | Installation |
|---|---|---|---|
| Solid (round head) | Steel, copper, aluminum | Structural, boilers, bridges | Heat, insert, buck (hammer head) |
| Countersunk | Steel, aluminum | Flush surfaces (aircraft, ships) | Same, but countersunk hole |
| Pop rivet (blind) | Aluminum, steel | Sheet metal, light duty | Rivet gun (one-side access) |
| Tubular | Brass, copper | Leather, fabric, light metal | Setter and anvil |
Riveting was the primary structural joining method before welding. The Eiffel Tower, Titanic, and Golden Gate Bridge were all riveted. Still preferred where vibration would crack welds.
Chapter 8: Weld Defects and Inspection
| Defect | Cause | Prevention |
|---|---|---|
| Porosity (gas holes) | Moisture, contamination, wind | Clean metal, dry electrodes, shield from wind |
| Undercut (groove at toe) | Too much heat, wrong angle | Reduce amperage, correct angle |
| Lack of fusion | Too little heat, wrong technique | Increase amperage, proper manipulation |
| Cracking | Rapid cooling, hydrogen, high carbon steel | Preheat, use low-hydrogen rods, slow cool |
| Spatter | Arc too long, wrong polarity | Shorten arc, check settings |
| Distortion (warping) | Uneven heating/cooling | Tack weld first, alternate sides, clamp |
Reference Card
- Forge welding: white heat + borax flux + hammer center first, work outward
- Arc welding: match electrode to metal type; arc length = electrode diameter
- E6011 for dirty/rusty metal; E7018 for strongest structural welds
- Oxy-acetylene: neutral flame for steel welding; preheat + oxygen blast for cutting
- Brazing and soldering work by capillary action: tight fit is critical
- Always clean the joint (grind, wire brush, degrease) before any welding method
- Preheat high-carbon steel and cast iron to prevent cracking
- Inspect every weld: look for undercut, porosity, cracks, and lack of fusion