Inputs in · verified reports out
Engineering calculations that outlive
the engineer who built the spreadsheet.
Somewhere on your server sits Design_Calc_FINAL_v7.xlsx. It sizes everything you ship, one engineer understands it, and nobody else is allowed to touch it. We pull that logic out and rebuild it as a validated system — inputs checked before they run, results flowing straight into CAD, and an audit-ready report printed on every run.
Design inputs → Validated calculation engine → CAD parameters + audit-ready report
The problem
The spreadsheet nobody is allowed to touch
It started as a quick calc. Fifteen years later it's forty linked sheets, three retired authors, and a warning in cell A1. Your production output depends on it every single day — and that's not a tooling preference, it's a standing risk.
One wrong cell away
The failure modes are quiet, and they compound:
- ×Fragile by design. Edit the wrong cell and a dependency three sheets away silently changes.
- ×Garbage in, report out. Nothing stops an out-of-range input from flowing straight into a final result.
- ×No memory. Six months on, nobody can say who ran the calc or which version of the rules it used.
- ×Retyped into CAD. Results travel to the model by copy-paste, and every retype is a chance to get it wrong.
Logic that behaves like software
- ✓Every input interrogated. Ranges, units, and combinations are checked before a single formula runs — including the branching cases Excel handles badly.
- ✓Results flow into CAD. Calculated values set model parameters directly. The number in the report is the number in the drawing.
- ✓Reports write themselves. Each run produces a PDF or Excel report with the full derivation and pass/fail status attached.
CHECKED INPUTS · TRACEABLE RESULTS · ONE SOURCE OF TRUTH
Results
From fragile formulas to audit-ready calculation reports
Inputs that can't lie
Range and unit checks stop bad data before it ever becomes a bad result.
Reports on demand
A submittal-ready document falls out of every run — derivation and pass/fail included.
CAD that follows the math
Calculated values drive geometry directly. No retyping, no drift between report and model.
A full audit trail
Every input, rule version, and output is recorded — compliance answers in minutes, not archaeology.
Process
From workbook to working system
Your spreadsheet isn't the enemy — it's the spec. We extract the engineering from it, then retire it with honors.
Untangle the logic
We map what the workbook actually does — every formula, branch, and hidden dependency — into a documented calculation model your engineers sign off on.
Rebuild it as an engine
The model becomes versioned, input-validated code. Same inputs, same answer — on every machine, for every user, with no quiet overrides.
Wire in the reporting
Your report format becomes a template the engine fills on every run: inputs, derivations, code references, results.
Connect it to CAD
Validated outputs set model parameters automatically. Change a design input and the model and report both update.
The honest answer
Couldn't we just clean up the Excel?
For one small, isolated calc — yes, and you should. The trouble starts when the calc feeds manufacturing: more sheets, more authors, more silent coupling. At that point "cleanup" means rewriting your engineering in a medium with no version control and no tests.
- ×Auditing a formula means clicking through cell references by hand
- ×One accidental edit ships wrong numbers without any alarm going off
- ×Nothing forces a check before the sheet is copied for the next job
- ×"How did we get this number in March?" has no answer
- ✓Rules live in versioned code, reviewed like any engineering document
- ✓A failing input stops the calculation — loudly, before output
- ✓Reports, drawings, and revisions all read from the same result
- ✓Any past result can be reproduced from its recorded inputs
"If a number can stop a shipment, the process that produced it should be testable."
Capabilities
The calculations we automate most often
If it has inputs, rules, and a report at the end, it's a candidate. These are the ones that come up again and again — because they touch safety, cost, and what can actually be built.
Mechanical
Load cases, member sizing, connection checks
Thermal & Fluid
Heat transfer, insulation sizing, HVAC loads
Electrical
Cable sizing, voltage drop, protection coordination
Mfg & Costing
Takeoffs, weight estimates, cost roll-ups
Compare
One calculation, two ways: Excel vs. an automated system
Take a calc your team ran this week and read it down both columns.
| Aspect | Excel Spreadsheets | Automated System (FDES) |
|---|---|---|
| Error Rate | Research puts errors in ~88% of spreadsheets — and Excel fails silently, not loudly. | Logic is locked, validated, and version-controlled. A formula can't be edited by accident, so it can't silently break. |
| Calculation Speed | Each manual cycle eats 30–60 minutes of an engineer's attention | Under 5 minutes, with inputs validated on the way in |
| Audit Trail | The file has no memory of who changed what, or when | Inputs, formulas, outputs, and timestamps — recorded on every run |
| Report Generation | Copy the numbers into a Word template, format, hope nothing moved | A branded, submittal-ready report generated automatically |
| CAD Integration | Values walk from Excel to CAD by hand, one retype at a time | Calculation outputs set CAD model parameters directly |
| Knowledge Retention | Lives in one person's head and one file on their desktop | Captured as documented, maintainable logic the whole team owns |
| Scalability | Interlinked workbooks collapse under their own complexity | Thousands of variants, one engine, identical behavior every time |
Who it's for
Do you recognize your team here?
If a spreadsheet failure would cost you a redesign, a recall, or a customer — this page was written for you.
Structural & Mechanical Engineers
You run the same design calcs in Excel every week — and at least once, a wrong-cell edit has made it all the way to a drawing.
Compliance-Driven Industries
An auditor will eventually ask how a number was produced. You'd rather answer in minutes than reconstruct it over days.
Teams with Knowledge Silos
The calc sheet only one or two senior engineers understand. When they're on leave, quotes and projects wait.
CAD-Integrated Workflows
You're done retyping Excel results into model parameters and hoping the two still match at release time.
FAQ
The questions engineering managers ask first
Can you automate calculations from our existing Excel spreadsheets?
Yes — the spreadsheet is usually where we start. We audit it, extract the engineering logic it encodes, and rebuild that logic as a version-controlled system. Your engineers verify the new engine against the old sheet's results before anything goes live.
Do generated reports comply with engineering standards?
Yes. Reports follow your templates and formatting, and each check can cite the applicable codes — IS, AISC, Eurocode, and others — so the output is ready for submittal or audit without rework.
Can calculations update automatically when CAD models change?
Yes, and this is where much of the value sits. When a model parameter changes, the linked calculations re-run and the report regenerates — documentation never lags behind the design, and nothing is re-entered by hand.
What output formats are supported?
PDF, Excel, Word, and HTML. Per project we configure branding, revision tracking, and, where required, digital signatures.
Client results
Measured on live deployments, not demos
"We had decades of engineering knowledge trapped in fragile spreadsheets. FDES extracted the logic, validated it, and now our calculations run in seconds with full traceability. Our audit submissions went from days to hours."
Industries
Where these calculation systems run today
Free · no obligation
Pick your most fragile spreadsheet. We'll show you what it becomes.
Send us one real Excel calculation your team depends on. The free audit shows exactly how it turns into a validated, CAD-connected system — before you commit to anything.
- One production Excel calculation examined line by line
- Its fragile spots and missing checks called out
- A concrete plan from workbook to validated engine
- Costs and effort estimated up front — then it's your call
Related insights
Not convinced yet? Fair. Read these
Why Excel Spreadsheets Are Costing Your Engineering Team More Than You Think
The research says 88% of spreadsheets contain errors. Yours are sizing structures.
Read article → BUSINESS CASEHow to Calculate ROI on Engineering Design Automation
Put a number on the business case before you pitch it internally.
Read article → AUTOMATION STRATEGY5 Signs Your Engineering Team Is Ready for CAD Automation
Five signals that your team has quietly outgrown its manual workflow.
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