Know what to do next with your product idea.
You’ve got an idea you believe in. The Free Sprint turns it into two things you can use straight away: a Specification you can hand to any engineer, and a Viability Report covering market potential, opportunities, challenges, timeline and cost. 60 to 120 minutes. You decide what to do next.
Built for people with an idea they believe in.
FIT · WHO THIS IS FORMost product ideas stall in the gap between “I have an idea” and “I know what to build”. Weeks of research, conflicting advice, and expensive early decisions that turn out wrong. The Free Sprint compresses that into 60 to 120 minutes.
It uses the same structure a working engineer would apply in a paid consultation, scripted and reviewed against real manufacturing constraints. The output is yours, and it’s portable – take it to us, to an independent engineering or design practice, or sit with it.
One continuous path. Two phases.
FRAMEWORK · WHERE WE WORK
The Free Sprint is the first pass through the early stages (sub-activity 01.04) and produces the Specification and Viability Report. The full 10-stage framework, what happens at each stage, and where AI stops and people start is on the How It Works page.
Four packages. Start free. Go deeper only when it earns its keep.
PACKAGES · FIXED FEEFree Sprint
An AI-guided interview through stages 01–05. Two outputs: a portable Specification and a Viability Report. Full mechanism on the Viability Sprint page.
Start the free sprint →Engineer-Verified Review
A working engineer reviews your sprint output, sharpens the numbers, flags what AI missed, and gives you a clear viability assessment.
- Everything in Free Sprint, plus
- 30-minute engineer video review
- Refined cost estimates (supplier-informed)
- Risk flags AI may have missed
- Manufacturing method recommendation
- Written summary within 48 hours
Expanded Specification
Your sprint and review output transformed into a professional, branded specification document – ready for investors, manufacturers, or engineering teams.
- Everything in Engineer Review, plus
- Branded Product Specification (.docx)
- Prioritised requirements summary
- Design Brief document
- Investor / funder-ready formatting
- Engineer-ready formatting
Handover-Ready Package
A dedicated handover session with a custom development roadmap, manufacturing strategy, and direct introduction to the engineering team.
- Everything in Expanded Spec, plus
- 1-hour specialist consultation (video)
- Custom development roadmap
- Manufacturing strategy & method selection
- Supply chain considerations
- Direct Cast Iron CAD team introduction
- Priority engineering quotation
ALL PAID PRICES INC. VAT · FIXED FEE · NO SCOPE SURPRISES
What you walk away with.
OUTCOME · WHAT YOU KEEPThe source of truth for the idea.
- Product concept statement
- Prioritised requirements (must / should / could)
- Structured product specification
- Portable – hand it to any engineer or practice
Direction, not a verdict.
- Brief summary and spec summary
- Market potential read
- Opportunities and challenges
- Timeline estimate and potential cost bands
Engineered by the team behind 280+ products.
AUTHORITY · 280+ PRODUCTS · 15 YEARS
Cast Iron CAD has engineered over 280 products across 15 years. Consumer goods, industrial plant, bespoke builds – products in people’s homes and on factory floors today.
Innovate Engineer distils that methodology into structured tools, so the same discipline is available without a paid consultation. The sprint is the same conversation we would run, scripted by experienced engineers and reviewed against real manufacturing constraints.
Questions people ask before starting.
FAQ · BEFORE YOU STARTIs it really free?
Yes. No payment, no sign-up, no lead-nurture sequence. If you want a human to review the output with you, that is the £129 Engineer-Verified Review – separately, only if you want it.
How long?
A full, considered run takes 60 to 120 minutes depending on how much you bring and how deep you want to go. The first structured summary inside the GPT appears in around 15 minutes – that is a checkpoint, not the finished output.
Who is it for?
Founders, inventors, and pre-launch creators with an early-stage physical product idea. Not apps. Not services. Things that get made, packed, and shipped.
Who sees my idea?
Your session runs inside a custom GPT on your own ChatGPT account. We don’t see or review individual sessions. If you book the Engineer-Verified Review, you choose what to share and when.
How accurate?
The sprint returns confidence-rated ranges, not single figures. Directionally useful for shaping the next decision. The paid Engineer-Verified Review narrows them using real manufacturing data.
What if it fails?
That is the point. Finding out early, before you spend on CAD or tooling, is the win. You keep the Specification and Viability Report either way and can come back when the idea matures.
If it’s not for you, close the tab.
No payment. No sign-up. No sales call. Keep whatever’s useful, come back when the idea matures. Nothing to cancel, nothing to undo.