Engineering Solutions
Six engineering answers to six different questions about a drawing: general machining, complex geometry, prototypes, micron tolerances, low volume and assembly. They are not a menu of machines — they are the routes a part takes once the file has been reviewed.
This page is the review layer of Engineering Solutions at Shenzhen XS Precision. It shows how a drawing is read before it is priced, which risks are checked in which order, and how to tell which of the six routes your part is on. Every route below links to the page that covers it in full.
The file is read before it is priced
Two quotations for the same drawing can sit fifteen percent apart without either shop being dishonest. The usual reason is not the hourly rate. It is that one of them read the file first: which callouts carry the function, how many times the part has to be let go of, how it will be measured, and what has to happen to the surface afterwards. The other one multiplied a shape by a cycle time.
So the review runs as five gates in a fixed order, and the order matters. Surface treatment cannot be agreed before tolerance risk, because anodising grows the part. Heat treatment cannot be placed after finishing, because hardening moves it. The price only exists once the five gates are closed — anything still open is written on the quotation as an assumption rather than left inside the number. That is the standing rule at XS Precision, and it is why the quotation arrives with a process plan attached to it.
None of the five gates is a formality, and none of them is billed separately. They are the reason a first article passes on the numbers rather than on an operator adjusting something at the machine, and the reason a repeat order behaves like the first one.
Six routes out of one drawing review
Each route below answers a different engineering question, which is why they cannot be compared like a price list. Read the one that matches your part and the detail is on its own page, with the numbers behind it.
Which route your drawing takes
Most drawings announce their own route. The table below maps what is on the drawing to the route it belongs on and to what you get back from it — so you can go straight to the page that answers your question.
| What is on the drawing | Route it takes | What comes back |
|---|---|---|
| Deep cavities, thin walls, sharp internal corners, compound angles | Complex Geometry Parts | Tool-access analysis, the feature that drives the price, and a DFM note on what a larger radius would save |
| Micron callouts with an inspection report requirement | High Precision Components | An error budget, the gauge selected for every critical callout, and a report with stated measurement uncertainty |
| A design still changing, or first real parts before tooling | Prototype Manufacturing | Parts in the production material with DFM feedback, so the changes happen before the tooling does |
| A defined part, fifty to five thousand pieces a year | Low Volume Production | Fixed and variable cost split, the quantity breaks that matter, and when dedicated workholding pays for itself |
| Several machined parts that arrive as one unit | Assembly Services | Torque and clamping control, a cleanliness spec, and a build record that traces to each component |
| General parts where price and lead time come first | Precision CNC Machining | A process plan naming the machines, the setup count and the cycle split, with the price attached to each |
Two routes on one drawing is normal rather than unusual. A first-article fixture plate that has to be flat to ten microns is Prototype Manufacturing and High Precision Components at the same time; a bracket in a two-hundred-piece order is general machining plus the low-volume cost curve. The review names both, so the quotation cannot hide one inside the other.
Where the risk actually sits
Six things cause most of the rework in this trade, and all six are visible on the drawing before anyone cuts metal. Naming them at quotation time is cheaper than discovering them at first article, so this is the list XS Precision walks through on every new part number.
What the material does about it
Material choice decides which of those risks are live. The same geometry behaves differently in 6061 and 7075, and differently again in titanium. This is the shortlist the review starts from, with the material pages linked below.
Stock position is part of the review rather than a purchasing detail. A grade that is not on the rack adds sourcing time to the lead time, and an equivalent grade that is — 6082 for 6061, 303 for 316 on a non-welded part — shortens it without changing the function.
Where an equivalent is suggested, the differences are stated: corrosion behaviour, weldability, machinability and how it behaves after coating. The material pages linked at the bottom of this page hold the longer version of each of those arguments.
Surface treatment changes the size
This is the step most often left out of a quotation and then discovered when the parts come back from the finisher. Coatings add material to every surface they touch: bores close up, outside faces grow, and a fit that was measured before the bath does not measure the same after it. The review decides the allowance before the price, not after the parts — XS Precision measures on both sides of the treatment so the report proves the result instead of asserting it.
The order is fixed: deburr, machine the critical features, measure, treat, measure again. Treating before the last cut hides the growth inside the tolerance; treating without a second measurement leaves the growth unverified.
Where a coating would eat a tolerance the function needs, the review says so and offers the alternative: a conversion coating that does not change size, a masked area, or a relaxed callout on a face that only has to look right.
Engineering Solutions, answered
How is this page different from the capability pages under it?
This page is the review layer: how a drawing is read, which risks are checked in which order, and which route a part takes. Each page below it takes one route and goes deep, with the process detail, the tolerances and the inspection data behind it. Start here when you are not sure which of the six you need.
Do I need to send a drawing before you can say anything useful?
A STEP file on its own gets a geometry answer with the assumptions written out. A PDF drawing with tolerances, datums, material and finish gets a real number with much less assumption in it. The review is the same work either way; what changes is how much of the quotation has to be a safety margin.
Which of the six routes applies to my part?
Most parts touch two of them. A one-off fixture plate that has to be flat is prototype work and precision work at once; a bracket in a two-hundred-piece order is general machining with the low-volume cost curve attached. The table above maps the usual cases, and the review names both routes when both apply.
How long does the engineering review take?
One working day for parts inside the process window. Longer when a feature needs a fixture designed or a process trial run, in which case XS Precision states the reason with the quotation instead of letting the date move quietly.
Will you tell me a feature is over-specified without changing my design?
Yes, and it is the most common note returned. A tight tolerance on a face that carries no fit changes nothing except the price, so it is marked on the quotation with what relaxing it saves. The functional dimensions are never touched by that suggestion.
What about surface finish and coating tolerances?
They are reviewed before the price, not after the parts return from the finisher. Anodising grows the part, plating grows it more, and bead blasting changes the roughness it is measured against. The allowance goes into the drawing review, and the parts are measured both before and after treatment so the report can prove it.
The rest of the site
Send the drawing, get the route and the price
Upload a drawing and XS Precision returns the engineering review, the route your part takes, the machines it will run on, and a price split into one-off cost and piece cost — usually inside one working day.
Accepted formats: STEP / STP / IGES / PDF / DWG / DXF. If there is no drawing yet, send the model and a note on what the part does: the assumptions will be written on the quotation rather than hidden inside it.