Tolerance Interpretation
The fine print,
read for you.
ISO 2768, decimal-place rules, fit classes, the title-block notes nobody wants to chase. Mavlon finds the governing rule, applies the clear ones, and asks you about the rest - in plain English.
First drawing free · every tolerance traceable to its source.
Mavlon proposes the rule. You approve it, correct it, or keep it as a note.
The tolerance no one printed
Half the dimensions on the page
have no tolerance at all.
And every one of them still has to be inspected. So somebody - usually you, usually late - goes hunting through the general notes, the title block, a standard nobody keeps on the shelf, to find the rule that governs them. Read it wrong and the part is wrong, and no one finds out for six weeks.
Mavlon reads that rulebook for you. It finds the governing tolerance, applies the rules that are unambiguous, and brings you the judgment calls - the standards, the scope questions - one at a time, in plain words. It never invents a number to look certain.
It decides like a good apprentice.
It asks when it should.
The clear rules, it just handles. The ones that need judgment, it never guesses - it brings them to you.
One read. Every kind of tolerance.
Not one trick on one drawing. The whole vocabulary of the fine print - read, applied where it is clear, flagged where it is not.
Correct it in your own words
Tell it like you'd tell the new hire.
You don't fill in fields. You say what you mean - and Mavlon turns your sentence into the rule, shows you exactly what it understood, and applies it. Except it never forgets, and never argues.
“This only applies to welded parts.”
ISO 2768-m, scope limited to weld features only. Affects 12 dimensions - ready to apply.
The long version
Where a drawing's tolerances actually hide.
Look at almost any production drawing and count the dimensions with their own ± value. It will be fewer than half. The rest - the holes, the lengths, the diameters with a bare number beside them - still have to be inspected to a tolerance. It just is not printed next to them. It lives somewhere else on the sheet, and finding it is the part of FAI nobody enjoys.
For an AS9102 Form 3, every characteristic needs a tolerance and, increasingly, a documented source for it. So the question is never just “what is the tolerance?” It is “which rule governs this dimension, and where on the drawing did that rule come from?”
The three places the rule usually lives
General notes and the title block. A line like UNLESS OTHERWISE SPECIFIED followed by a decimal-place scheme - X ±0.5, 0.X ±0.3, 0.XX ±0.13 - sets the tolerance by how each dimension is written. A whole number is loose; a two-decimal number is tight. Read it wrong and every untoleranced dimension on the sheet inherits the wrong band.
A general tolerance standard. ISO 2768-m, ISO 2768-mK, ASME Y14.5 - a class reference that points to a published table. The drawing prints the class, not the numbers, and the inspector is expected to look them up. The standard must be recorded verbatim and never silently expanded into a value the drawing never showed.
Fit classes and range tables. A bore called Ø30 H7 carries an ISO 286 limit. A process table may say 0–30 is ±0.2 and 30–120 is ±0.3, matched by size. Each is a rule with a scope - and scope is exactly where mistakes happen.
Why getting the source right matters
A tolerance applied from the wrong note is not a small error. It is a part inspected to the wrong limit, signed off, shipped, and discovered six weeks later in someone else's receiving inspection. The cost is not the rework - it is the trust. That is why a defensible Form 3 shows not just the tolerance, but the rule it came from and the line on the drawing that rule was read from.
What interactive tolerance review changes
Mavlon reads all of it - the notes, the title block, the tables, the standards - and sorts every rule into two piles. The unambiguous numeric and range rules it applies to the untoleranced dimensions they govern, with the source shown. The ones that need judgment - a bare standard, an unclear scope, a fit class with no printed limits - it never guesses. It brings them to you one at a time, in plain language, and applies nothing until you say so. You correct a rule the way you would explain it to a junior inspector: “this only applies to welded parts,” and Mavlon turns the sentence into the rule. Every tolerance on the page ends up traceable to its source - and approved by you. See how Mavlon reads GD&T and ISO 2768 →
tolerance found
without your say-so
correct any rule
its source
See what governs your drawing.
Upload it and watch Mavlon read the fine print - then decide, in plain words, what to trust.
First one is free. No card, no setup.