Engineering Tools
Work the numbers before you send the drawing.
These are the checks an engineer does when a drawing lands. Running them first is the difference between a quote and a question, and between comparing two offers on unit price and comparing them on what actually lands.
Every tool is rule-based: it works from the numbers you enter and the capability data on this site. None of them pretend to be CAD analysis, none of them quote a price, and each one says so on the page.
Enquiry
RFQ Readiness Checker
Check an enquiry before you send it, and see which missing detail would have come back as a question instead of a price.
Outputs
- READY / PARTIALLY READY / MISSING INFORMATION
- The exact missing fields
- Engineering cross-checks
Supplier Fit Score
Score an enquiry against what this shop actually does, across capability, material, tolerance, quality, production and certification.
Outputs
- A 0-100 overall fit
- Seven scored dimensions with a reason each
- Combination warnings
Engineering
DFM Precheck
Run a rule-based manufacturability check on a feature list and see which of eleven common problems your design is exposed to, with the standard fix for each.
Outputs
- Per-rule risk assessment
- The fix a machinist would apply
- What to change before quoting
Unit & Metric/Imperial Converter
Convert length, cutting speed, feed, mass, force, pressure, temperature and roughness units between metric and imperial, on exact definitions rather than rounded tables.
Outputs
- The converted value
- The same value in every unit of the group
- What not to convert
Tolerance Calculator & Converter
Read a tolerance written as a ±, a limit pair or a unilateral allowance, turn it into a band in mm, µm, inches and thou, and see when it crosses into grinding.
Outputs
- Min/max material condition
- Band in mm, µm, inch and thou
- The equivalent ±
- A cross-check against the published machining limit
Surface Finish Converter & Selector
Convert a surface roughness between µm and µin, see which operations actually reach it, and get a target when you are starting from what the surface has to do.
Outputs
- The value in both units
- Operations whose typical band reaches it
- A target for the requirement
- Where the value crosses into polishing or lapping
Thread & Fastener Calculator
Turn a thread designation into its pitch, tap drill and clearance hole, and find the nearest equivalent in the other thread system.
Outputs
- Pitch and threads per inch
- Tap drill in both systems
- Clearance hole
- Nearest metric and inch equivalents
Hole & Shaft Fit Calculator
Enter the four limits from the drawing and find out whether the parts assemble by hand, need a press, or lock - and which side of the tolerance to tighten.
Outputs
- Clearance or interference at both extremes
- Clearance, transition or interference fit
- Which side carries the tolerance
- What the assembly will need
Machining Time Estimator
Turn feed, speed and setup into a cycle time and a batch time, and show how much of the batch is the setup rather than the cutting.
Outputs
- Feed rate
- Cycle time per part
- Batch time including setup
- The setup share of the batch
CNC Process Selector
Describe the part - shape, size, quantity, tolerance, material and features - and see which process would make it, with the rule that decided it and the operations it will also need.
Outputs
- The primary process, with the reason
- The operations the part also needs
- Where the part is likely to cost more than it looks
GD&T Reference
Look up what each geometric control actually controls, whether it needs a datum, and what it does not say - which is where drawings usually go wrong.
Outputs
- What the control controls
- Whether a datum is required
- The misunderstanding that costs money
- What the modifiers change
CNC Design Rule Checker
The rules a cutter actually obeys - corners, pockets, threads, datums, burrs - each with why it exists and what to do instead, plus what we publish about our own capabilities.
Outputs
- The design rules, with the reason for each
- What to change instead
- Our published capabilities, each classified
- The modifiers that matter
Materials
Material Selector
Describe the service conditions and get a shortlist from the 100 grades the shop actually publishes, each with the reason it is on the list.
Outputs
- Top three grades with reasons
- Alternatives from the same dataset
- What to confirm before specifying
Part & Material Weight Calculator
Work out the weight of the stock from its shape and the density published for the grade, for one piece or a batch, with the material cost if you have a price.
Outputs
- Weight per piece
- Batch weight
- The density used, and where it comes from
- Material cost from your own price
Material Comparison
Put two published grades side by side - density, tensile, hardness, machinability on the shop scale, cutting data and lead time - and see what the difference means.
Outputs
- Property-by-property comparison
- Computed density and tensile differences
- What the gap means for cycle time and weight
- Where the families differ beyond the table
Heat Treatment Selector
See what condition and treatment we publish for a grade, and what each common treatment actually does - without inventing a temperature or a soak time.
Outputs
- The published condition and heat treatment for that grade
- Treatments normally applied to the family
- What each one does, and how it goes wrong
Commercial
Total Landed Cost
Turn a unit price into the number that actually lands: tooling, inspection, packaging, freight, insurance and duty, plus the per-unit share of each.
Outputs
- Line-by-line landed cost
- Per-unit landed cost
- The share of the total that is not the part price
Lead Time Estimator
Read the lead time we publish for a product family or a material grade, add your own finishing, inspection and transit, and see the total in working days.
Outputs
- The published range, and where it comes from
- The range in working days
- Your adders and the total
- The published MOQ for the family
CNC Cost Driver Calculator
Rank what is actually driving the cost of a part - material, tolerance, batch size, features, finishing, inspection - and see which one to change.
Outputs
- The drivers, ordered by influence
- Why each one costs what it costs
- What to change to move it
- Where the price is concentrated
BOM Cost Estimator
Roll several parts - each with its own price, quantity and one-off tooling - into one total, and see which line owns the money.
Outputs
- Line cost, line share and tooling share
- Parts and tooling subtotals
- Grand total with freight and duty
- Where the spend is concentrated
Incoterms Cost Calculator
Compare two Incoterms 2020 rules segment by segment - who pays export clearance, freight, insurance, duty - and see where risk turns over against the cost.
Outputs
- Which party pays each of seven cost segments
- Where the two rules differ
- Where risk passes, and where cost does
- What each rule is commonly misused for
MOQ & Quantity Economics
See the published MOQ for a family against the quantity you want, and what the extra parts in a price break actually cost - which is not the same as the unit price.
Outputs
- Whether you clear the published MOQ
- The unit price fall
- The cost of the NEXT part
- Whether the break is real or arithmetic
This is the first set. The Tool Center is being extended with tolerance and unit converters, thread and fit calculators, a machining time estimator, a surface-roughness converter and an Incoterms calculator, each one built and published the same way: rules stated, limits stated, no invented numbers. Tools that are not listed here do not exist yet.

