Formulas to Track Welding Side Hustle Profit (Spreadsheet)

I remember the first time I realized my side business was actually costing me money. I had just finished a custom headache rack for a local landscaper. I spent three nights in the shop, burned through a fresh bottle of 75/25 gas, and used a significant amount of TIG rod. When I handed over the invoice for $450, I felt proud. Then, I sat down with a legal pad and did the math. After subtracting the cost of the steel, the gas refill, the electricity, and the sanding discs, I had earned about $5.50 per hour. I could have made more money flipping burgers with zero overhead and no risk of flash burn.

That moment changed how I viewed my workshop. I stopped treating it like a hobby and started treating it like a machine that requires fuel—financial fuel. If you are a fabricator looking to transition from a hobbyist to a professional, you need more than just a steady hand and a good bead. You need a way to track every penny that leaves your pocket. By using simple arithmetic within a basic digital ledger, you can transform your shop from a “money pit” into a legitimate source of income.

Establishing a Realistic Hourly Shop Rate

A shop rate is the total dollar amount you must charge for every hour of work to cover your expenses and pay yourself a fair wage. Many new fabricators pick a number out of thin air, like $50 an hour, because it sounds like a lot. However, without calculating your actual costs, that $50 might not even cover your shop’s lights and insurance.

To find your true rate, you must identify your fixed costs. These are the bills you pay whether you strike an arc or not. This includes shop rent (or a portion of your mortgage), business insurance, basic utilities, and any subscriptions for design software. You take the sum of these monthly costs and divide them by the number of hours you actually plan to work.

If your fixed costs are $400 a month and you work 40 hours a month on your side hustle, your “overhead burden” is $10 per hour. If you want to take home $40 an hour in profit, your baseline shop rate must be at least $50. But we aren’t done yet. You also have to account for the time you spend cleaning, quoting, and driving to the steel yard. This is “non-billable” time. If you spend 10 hours a month on these tasks, you only have 30 hours to actually make money. Now, that $400 overhead is divided by 30, making your burden $13.33 per hour.

Expense Category	Monthly Cost	Hourly Impact (40 hrs/mo)
Shop Space/Utilities	$250	$6.25
Insurance & Fees	$100	$2.50
Consumable Reserve	$100	$2.50
Total Fixed Burden	$450	$11.25

Why Non-Billable Time Kills Profitability

Non-billable time refers to any hour spent in the shop that a customer isn’t directly paying for, such as sweeping floors or maintenance. If you don’t account for this in your hourly rate, you are essentially working for free during those hours. Building a simple multiplier into your spreadsheet can help account for this. I usually suggest a 1.2x multiplier on your labor hours to cover the “hidden” work of running a shop.

Mapping Machinery Depreciation and Equipment ROI

Machinery depreciation is the process of spreading the cost of a tool over its useful life to ensure you have funds to replace it later. Every time you pull the trigger on your MIG gun, you are wearing out the machine. If you don’t charge for that wear and tear, you will be broke when the machine finally quits.

I like to use a “cost per hour” model for my major tools. Let’s say you buy a high-quality TIG welder for $3,000. You expect it to last for 2,000 hours of arc time. By dividing the price by the hours, you see that the machine costs you $1.50 for every hour it is running. In your spreadsheet, you should have a column for “Equipment Use” that adds this small fee to every job.

This isn’t just about saving for a rainy day; it’s about calculating your return on investment (ROI). If a $2,000 plasma cutter saves you three hours of manual grinding on every project, and your shop rate is $60, the tool pays for itself in about 11 projects. Knowing this number helps you decide if a new tool is a smart business move or just a shiny new toy.

• Step 1: List the tool and its purchase price.
• Step 2: Estimate how many years it will last.
• Step 3: Divide the price by the years, then by your annual billable hours.
• Step 4: Add this “hourly tool tax” to your shop rate.

Calculating the Consumable Burden in Small Batch Projects

The consumable burden is the total cost of items that are used up during a project, such as welding gas, wire, abrasives, and electricity. These are often the most underestimated costs in a small shop. A single 4.5-inch grinding disc might only cost $2, but if you use five of them on a project and don’t charge for them, you just lost $10 of profit.

In my experience, the most accurate way to track this without going crazy is to use a “Consumable Percentage.” For most general fabrication, consumables usually equal about 10% to 15% of the total material cost. However, if you are doing heavy TIG welding on stainless steel, your gas and rod costs will be much higher.

I recommend keeping a simple log of how long a bottle of gas lasts. If a $60 refill lasts you 10 hours of arc time, your gas cost is $6 per hour. You can create a cell in your spreadsheet that multiplies your estimated “arc time” by this hourly gas rate. This ensures that the customer, not you, is paying for the argon.

• Welding Wire: Track the weight. A 33lb spool divided by its cost gives you a per-pound price.
• Shielding Gas: Track the tank pressure or hours of use.
• Abrasives: Track how many discs you use per project type (e.g., 2 discs per 10 feet of weld).
• Electricity: For most small shops, this is a minor cost, but for heavy plasma cutting or large welders, it can add $1–$3 per hour to your overhead.

Building a Reliable Job Estimation Model

A job estimation model is a formulaic approach to predicting the cost of a project before you start, ensuring you include materials, labor, and profit. One of the biggest mistakes I see is “guesstimating.” You look at a project and think, “That looks like $300 worth of work.” This is a recipe for disaster.

Instead, your spreadsheet should follow a strict logic. Start with the raw material cost. Never charge the customer exactly what you paid. You spent time sourcing the metal, driving to the yard, and loading it. A standard markup is 20% to 50% depending on the volume. If the steel costs $100, you charge the customer $130.

Next, add your labor. Be honest about how long the project will take. If you think it will take 5 hours, it will probably take 7. Always add a “fudge factor” of 15% to your estimated hours. Multiply these hours by your calculated shop rate. Finally, add your consumable burden. The sum of these three parts—Materials + Labor + Consumables—is your base cost. Then, add your desired profit margin on top of that.

Item	Calculation	Subtotal
Raw Steel	$150 + 30% Markup	$195.00
Labor	6 Hours @ $75/hr	$450.00
Consumables	15% of Material Cost	$22.50
Total Quote		$667.50

Why Material Markup is Non-Negotiable

Building on this, the material markup covers more than just your time. It covers “drops” or wasted material. If you have to buy a 20-foot stick of tubing but the project only uses 12 feet, the customer should pay for the whole stick unless you are certain you can use the remaining 8 feet on another paid job soon. Otherwise, you are subsidizing their project with your inventory.

Analyzing Post-Project Profitability and Variance

Post-project profitability analysis is the act of comparing your original estimate to the actual time and money spent once the job is finished. This is where the real learning happens. If you quoted 10 hours but spent 15, your spreadsheet will show a negative variance. You need to know why. Did you hit a snag? Was the material dirtier than expected?

Interestingly, most fabricators find that they are consistent in their errors. You might notice that you always underestimate grinding time by 20%. By tracking this variance over five or ten jobs, you can adjust your future formulas. If your spreadsheet shows you are consistently over-budget on abrasives, you can raise your consumable percentage from 10% to 15%.

This practice also helps you identify which types of jobs are your “money makers” and which are “time sucks.” You might find that small repair jobs have a much higher hourly profit than large, complex builds. As a result, you can start steering your side hustle toward the work that actually builds your bank account.

• Actual Labor Hours: Record every minute spent on the job.
• Actual Material Used: Note if you had to buy extra or if there was high waste.
• Profit Variance: (Actual Income - Actual Expenses) / Actual Hours. Compare this to your target shop rate.

Managing Bulk Sourcing and Inventory Math

Sourcing materials in bulk can significantly lower your costs, but it requires careful tracking to ensure the savings reach your bottom line. When you buy a full lift of steel or a dozen cases of grinding discs, you are tying up cash. Your spreadsheet should track the “unit price” of these items so you can accurately charge for them as they are used.

For example, if you buy 50 flap discs for $100, your unit cost is $2. When you do a job that uses 4 discs, you charge $8 (plus markup). If you don’t track the unit cost, you might forget how much you paid six months ago and undercharge. This is especially important with steel prices, which can fluctuate wildly.

I suggest having a “Materials Library” tab in your workbook. List the date of purchase, the total quantity, and the price per foot or per piece. When you start a new quote, you can pull the most recent price from this list. This ensures your quotes reflect current market realities rather than what you paid three years ago.

1. Track by the foot: For tubing and angle iron, always break it down to a per-foot price.
2. Track by the pound: For plate or sheet metal, use a per-square-foot or per-pound price.
3. Update frequently: Check your local supplier’s pricing every month to adjust your baseline.

Calculating the Payback Period for New Technology

As your side hustle grows, you will be tempted to buy faster or more precise equipment. A CNC plasma table or a high-end pulse MIG welder can be game-changers, but only if they generate a positive return. To calculate this, you look at the “Payback Period,” which is the amount of time it takes for the tool to pay for itself through increased efficiency or new capabilities.

Let’s say a CNC plasma table costs $5,000. It allows you to cut parts in 10 minutes that used to take you 2 hours by hand. If your shop rate is $60, you are saving $110 in labor per project. To find the payback period, divide the tool cost by the savings per project. In this case, $5,000 / $110 = 45.4. You need about 46 projects to pay for that table.

If you only do two of those projects a month, it will take nearly two years to break even. However, if that table allows you to take on new types of work you couldn’t do before, you also have to factor in that “new” income. A simple ROI calculation in your ledger can prevent you from over-leveraging yourself on equipment that your current volume doesn’t justify.

The Hidden Costs of Shop Utilities and Power

Many side-hustlers ignore electricity and heating because the bills are often combined with their household expenses. However, a high-voltage welder or a large air compressor can noticeably spike a residential power bill. While it’s difficult to measure exactly how many cents of power a single weld uses, you can estimate the “Utility Load.”

Look at your power bill during a month when you aren’t working in the shop, then compare it to a month when you are busy. The difference is your shop’s energy cost. Divide that by your billable hours. Usually, it’s a small amount—maybe $1 to $2 per hour—but it’s a real expense. Adding a “Utility Surcharge” to your hourly rate ensures that you aren’t paying the power company out of your own pocket.

Building on this, don’t forget the cost of heating or cooling your space. If you have to run a propane heater for two hours to get the shop warm enough to weld, that propane is a job cost. If a tank of propane costs $20 and lasts 10 hours, you need to add $2 for every hour of shop time in the winter.

Strategic Markup Levels by Job Complexity

Not all jobs should be priced the same. A simple “weld this bracket back on” repair is different from “design and build a custom spiral staircase.” The more complex the job, the higher your markup should be. This is because complex jobs carry more risk. If you mess up a simple repair, it’s a $20 fix. If you mess up a staircase, it could cost you thousands.

I use a tiered markup system in my quoting logic: * Tier 1 (Simple Repair): Standard shop rate + 10% profit margin. Low risk, fast turnaround. * Tier 2 (Custom Fabrication): Standard shop rate + 20% profit margin. Requires design time and precise cuts. * Tier 3 (Structural/Complex): Standard shop rate + 35% profit margin. High liability, complex geometry, or expensive materials.

By adjusting the “Profit Margin” cell in your spreadsheet based on the tier, you ensure that you are being compensated for the extra stress and skill required for difficult projects.

Common Mistakes in Fabrication Cost Accounting

The most common mistake I see is “rounding down” to win a job. You see a competitor charging $400 for a bumper, so you charge $350 even though your math says you need $420 to be profitable. When you do this, you aren’t “winning” a job; you are volunteering to pay for the privilege of working.

Another mistake is failing to account for “Shop Consumables” that aren’t welding-specific. This includes things like: * Hand soap and shop towels. * Broom heads and floor dry. * Drill bits and bandsaw blades. * Marking pens and layout fluid.

These items seem cheap, but they add up to hundreds of dollars a year. A simple way to handle this is to add a flat “Shop Supply Fee” of $5 to $10 to every invoice. Most customers won’t blink at a small fee for shop supplies, and it ensures these small costs don’t erode your take-home pay.

Actionable Next Steps for Your Shop Ledger

To get started, you don’t need fancy software. A basic spreadsheet with a few columns is all it takes to gain clarity. Start by listing every expense you’ve had in the last three months. This is your baseline.

1. Calculate your fixed monthly overhead.
2. Determine your target take-home hourly wage.
3. Set your billable hour goal (how many hours can you realistically work?).
4. Create a “Quote Template” sheet that links to a “Material Price List.”
5. Log every hour you spend on your next project, including the time spent talking to the customer.

By the time you finish your next three projects, you will have enough data to see the “truth” of your business. You might find you need to raise your rates, or you might find you are more profitable than you thought. Either way, you will be making decisions based on data, not guesswork.

FAQ: Mastering Workshop Economics

How do I calculate my shop rate if I work out of my home garage? Even if you aren’t paying extra rent, the shop occupies space that has value. Calculate the square footage of your shop as a percentage of your home. Apply that same percentage to your mortgage/rent and utilities. This gives you a “fair share” cost that the business should pay back to the household.

What is a standard markup for steel and aluminum? For small shops, a 30% to 50% markup is standard. This covers the time spent sourcing, transporting, and storing the material. If you have to spend two hours driving to a specialty supplier, your markup should be higher to cover that time.

How do I factor in the cost of my welding gas? The easiest way is to track how many hours of “arc time” a bottle provides. Divide the refill cost by those hours. If a $70 bottle lasts 10 hours, add $7 per hour of welding to your quote.

Should I charge for the time I spend quoting a job? Yes, but usually indirectly. You shouldn’t list “Quoting Time” as a line item on an invoice, as it can frustrate customers. Instead, your hourly shop rate should be high enough to cover the non-billable hours spent on administration and sales.

What is the “Consumable Burden,” and why does it matter? It is the total cost of items that are destroyed or used up during fabrication, like discs, gas, and wire. It matters because these costs can easily eat 10–20% of your profit if they aren’t explicitly tracked and charged to the customer.

How do I know when it’s time to raise my rates? If you are consistently booked out more than a month in advance, or if your post-job analysis shows your “Actual Hourly Rate” is consistently lower than your target, it is time to increase your prices.

Is it better to charge by the hour or by the project? For custom work, “Value-Based Pricing” (per project) is usually better for the builder. If you are fast and efficient, an hourly rate punishes you for being good. A project price allows you to capture the value of your expertise. However, you must use your internal hourly rate to calculate that project price accurately.

How do I account for expensive specialty tools like a mag drill or cold saw? Use the depreciation formula. Divide the tool’s cost by its expected lifespan in hours. Add that small amount (e.g., $2/hour) to any job that requires that specific tool.

What do I do if a customer thinks my quote is too high? Show them the breakdown. Explain the cost of high-quality materials and the hours of labor involved. If they still refuse, they are likely not a profitable customer for you. It is better to have an empty shop than a shop full of work that loses money.

How often should I update my material pricing in my spreadsheet? In a volatile market, check your local steel yard’s prices monthly. Even a $0.10 per pound increase can significantly impact the profitability of a large project like a trailer or a fence.

What is “Variance,” and why is it important for my side-hustle? Variance is the difference between what you thought a job would cost and what it actually cost. Tracking this helps you find “leaks” in your business, such as slow welding speeds or high material waste, allowing you to fix them for the next job.

(This article was written by one of our staff writers, Michael Hargrove. Visit our Meet the Team page to learn more about the author and their expertise.)