Weld Time Calculator

MIG vs. TIG vs. Stick: How Process Choice Affects Time and Cost

The welding process you choose determines the project timeline more than any other variable. A 48-inch fillet weld on 1/4-inch steel takes roughly 15 minutes of total time with MIG, 35 minutes with TIG, and 25 minutes with stick. That 2× difference between MIG and TIG compounds across a project with hundreds of inches of welding.

**MIG welding (GMAW — Gas Metal Arc Welding)** is the production workhorse. A continuous wire electrode feeds through the gun, so the welder does not stop to change electrodes. Travel speeds of 10–25 inches per minute are typical, and the operating factor (percentage of time the arc is actually running) is the highest of any manual process at 30–40%. MIG excels on mild steel and aluminium in shop environments. The limitation is portability: MIG requires a shielding gas cylinder and wire feeder that do not travel easily to field locations. For fabrication shop work — railings, structural connections, equipment frames — MIG is almost always the fastest and cheapest process.

**TIG welding (GTAW — Gas Tungsten Arc Welding)** produces the highest-quality welds but at the slowest speed. The welder holds a non-consumable tungsten electrode in one hand and feeds filler rod with the other, which requires more skill and coordination. Travel speeds of 4–10 inches per minute are typical, and the operating factor drops to 20–25% because of the manual filler feeding and frequent torch adjustments. TIG is the standard for stainless steel, thin aluminium, chromoly tubing, and any weld where appearance matters — visible architectural metalwork, food processing equipment, aerospace tubing, and motorcycle frames.

**Stick welding (SMAW — Shielded Metal Arc Welding)** is the most portable and forgiving process. It requires no gas cylinder and works outdoors in wind that would blow away MIG or TIG shielding gas. Travel speeds of 5–12 inches per minute are typical, but the operating factor is only 20–30% because the welder must stop to chip slag and change electrode stubs every few minutes. Stick dominates field welding: pipeline work, structural steel erection, farm equipment repair, and anything done outside a shop. If the project involves [structural steel beams](/calculators/structural/steel-beam-size-calculator), field connections are almost always stick-welded because the beams are too large to bring into a shop after erection.

Travel Speed and Deposition Rate Reference

These figures represent typical production rates for a qualified welder working on mild steel. Actual rates vary by welder skill, position (flat, horizontal, vertical, overhead), and joint fit-up quality.

| Parameter | MIG (GMAW) | TIG (GTAW) | Stick (SMAW) | |---|---|---|---| | Travel speed (thin, ≤1/8") | 15–25 ipm | 6–10 ipm | 8–12 ipm | | Travel speed (medium, 1/4") | 10–15 ipm | 4–6 ipm | 5–8 ipm | | Travel speed (thick, 1/2"+) | 6–10 ipm | 3–5 ipm | 3–5 ipm | | Deposition rate | 3–8 lbs/hr | 1–3 lbs/hr | 1–5 lbs/hr | | Deposition efficiency | 93–98% | 95–99% | 60–70% | | Operating factor | 30–40% | 20–25% | 20–30% | | Shielding gas flow rate | 25–35 CFH | 15–25 CFH | None (flux) | | Gas type | 75/25 Ar/CO₂ | 100% Argon | N/A | | Electrode/wire cost per lb | $1.50–$3.00 | $5–$20 | $1.50–$4.00 |

Deposition efficiency is the percentage of filler material that ends up in the weld. MIG and TIG waste very little — the wire or rod melts directly into the joint. Stick welding wastes 30–40% of the electrode as stub ends and slag coating, which inflates the filler material cost per pound of deposited metal. This is the hidden cost of stick welding that does not show up in the per-rod price.

Labour rates for certified welders range from $25–$50 per hour (welder pay) but the shop billable rate — including overhead, equipment, consumables, and supervision — runs $65–$100 per hour as of March 2026, US national averages.

Understanding Operating Factor and Why It Matters

Welding presents serious safety hazards including arc flash (UV radiation), toxic fumes, fire, and electric shock. Always wear proper PPE: auto-darkening helmet (shade 10+ for MIG/stick, shade 8+ for TIG), FR leather gloves, FR jacket or apron, steel-toed boots. Work in ventilated areas or use fume extraction. Keep a fire extinguisher within 10 feet.

Operating factor (also called arc-on time or duty cycle in estimating contexts) is the single most misunderstood variable in weld time estimation. It represents the percentage of total clock time that the welding arc is actually running. The rest of the time goes to fit-up, clamping, repositioning the workpiece, cleaning, electrode changes, inter-pass cooling, and reading the print.

A beginner estimator might calculate arc-on time for 100 inches of MIG welding at 15 ipm and get 6.7 minutes. The actual clock time will be closer to 19 minutes because the arc only runs about 35% of the total time. Forgetting the operating factor underestimates a weld job by 2–4× — which is how fabrication shops lose money on fixed-price contracts.

Position affects operating factor heavily. Flat-position welding (the most efficient) keeps the operating factor near the top of the range. Vertical and overhead welding drop it to the bottom because the welder must control a smaller puddle, make shorter passes, and deal with gravity pulling the molten metal away from the joint. A project with 50% overhead welding takes 30–50% longer than the same welds done flat.

Joint fit-up quality also matters. If the two pieces being joined have uneven gaps, poor alignment, or mill scale on the surfaces, the welder spends extra time grinding, adjusting clamps, and compensating for inconsistent gaps — all of which is non-arc time. Spending an extra hour on fit-up and surface prep can save two hours of welding time by reducing rework and improving first-pass quality.

For projects that combine welding with other trades — like a [pergola where welded steel brackets connect to wood posts](/calculators/materials/pergola-size-and-spacing-calculator) — coordinate the welding schedule with the assembly schedule. Pre-fabricating welded brackets in the shop (where flat-position welding is possible) is always faster and cheaper than field-welding connections overhead.

Joint Types and When to Use Each

The four standard joint types each serve specific structural and practical purposes. Choosing the wrong joint for the application either wastes material (over-engineering) or creates a weak connection (under-engineering).

**Butt joints** connect two pieces aligned end-to-end in the same plane. They are the default for plate and pipe connections where the joint must carry full tensile strength. On thin material (under 1/4 inch), a square butt joint with no preparation is sufficient. On thicker material, the edges must be bevelled to allow full penetration — an unbevelled butt joint on 1/2-inch plate will only fuse the top surface while the root stays unwelded, creating a joint that looks solid but fails under tension.

**Fillet joints** form a triangular weld at the intersection of two pieces meeting at an angle — usually 90 degrees (T-joints and corner joints). Fillet welds are the most common joint in structural fabrication because they require no edge preparation (no bevelling) and are fast to weld. The weld size (leg length) is specified by the engineer, typically ranging from 3/16 inch to 3/4 inch depending on the load. A fillet weld sized at the material thickness provides roughly the same strength as the base metal.

**Lap joints** overlap two pieces and weld along one or both edges. They are simple to fit up and weld, but the overlapping material creates a stress concentration at the weld toe that makes lap joints weaker in fatigue than butt joints. Lap joints are common in sheet metal work, ductwork, and non-structural connections where the priority is ease of assembly rather than maximum strength.

**Groove joints (V-groove, bevel, J-groove)** are butt joints with prepared edges — the edges are ground or flame-cut to create a groove that allows the weld to fill the full thickness of the joint. Groove welds provide complete joint penetration (CJP) and are required by structural codes for connections that must develop the full strength of the base metal. The trade-off is time and cost: a V-groove on 1/2-inch plate requires 3–5 passes to fill, compared to a single pass for a fillet on the same thickness.

How to Estimate a Welding Job

1. **List every weld on the project.** Go through the fabrication drawings and catalog each weld: its length, joint type, weld size (fillet leg or groove preparation), and welding position (flat, horizontal, vertical, overhead). Group similar welds together — 20 identical fillet welds on a railing can be estimated as a batch.

2. **Choose the welding process.** This is usually dictated by the material, location, and quality requirements. Shop work on carbon steel: MIG. Field work or thick structural connections: stick. Stainless steel, thin material, or exposed decorative welds: TIG. Some projects use multiple processes — MIG for production welds, TIG for finish welds in visible areas.

3. **Calculate arc-on time per weld group.** Divide the total weld length by the travel speed for the process and material thickness. Multiply by the pass multiplier for groove or multi-pass fillet welds. This gives you the pure welding time.

4. **Apply the operating factor.** Divide arc-on time by the operating factor to get total clock time. For shop work with good fit-up, use the upper end of the operating factor range. For field work with difficult positions, use the lower end.

5. **Price the consumables.** Calculate filler wire/rod weight from the weld cross-section and length. Add 5–10% for waste (stub ends for stick, wire trim for MIG). Calculate shielding gas volume from arc-on time and flow rate. Price gas per cubic foot (typically $0.03–$0.08/cu ft for argon or 75/25 mix, March 2026).

6. **Add labour cost.** Multiply total clock hours by the shop or field rate. Do not forget mobilisation time for field work — getting the welder, equipment, and gas to the site and set up adds 1–4 hours to even a small field job.

7. **Add a complexity buffer.** For complex assemblies, overhead welding, or tight-access joints, add 15–25% to the estimated time. Weld estimating is notoriously optimistic — most shops track actual vs. estimated hours and find their initial estimates run 10–20% low.

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