Basics of a CNC Quotation Form

The form asks for a 3D CAD model first. A STEP or IGES file lets us open the geometry, check for thin walls, deep pockets and undercuts, and estimate the cutting time per setup. A PDF drawing on its own is not enough to program a machine, and a sketch is not enough to quote. Send STEP plus a 2D drawing with the tolerances and datum callouts that actually matter.

Not every dimension needs a tolerance. Mark the ones that control fit, function or assembly, and leave the rest to general machining. A drawing with ±0.005 mm on all dimensions tells us nothing about which features to hold, and it usually adds cost without adding value. If your part is a bracket with three clearance holes, say so.

Add the model in the orientation you expect it to be machined, or note the critical faces. It helps us see which side needs to sit on the fixture and which features need a fourth or fifth axis. For parts with complex geometry, a 5-axis setup can finish in one operation what a 3-axis machine would need three setups to reach.

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  Send STEP or IGESNative CAD is fine too. We need solid geometry, not just an image.
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  Tolerances on the drawingCall out critical fits and datums. Note the general tolerance block.
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  Note the material conditionTemper, hardness or heat-treat state changes the cutting parameters.

Write the alloy, not just 'aluminium'. 6061-T6 machines fast and holds a good finish. 7075 is stronger but tougher on tools. 316L stainless work-hardens and needs slower feeds. Inconel and titanium TC4 (Ti-6Al-4V) cut much slower and wear tooling, so the same part in 7075 and TC4 will not quote the same. If the material is open, say what the part has to do and we can suggest an alternative.

Quantity has the largest single effect on unit price. Programming, fixture design and the first-article setup are fixed costs. Spread over 5 parts, they dominate the price. Spread over 500, they almost disappear. This is why a quote for one prototype and a quote for a production run look so different even when the geometry is identical.

There is no minimum order quantity here. We run from a single prototype to 10,000+ part runs, and we will tell you where the price curve flattens. If you expect to scale later, say so in the notes. We can quote the prototype and the production volume side by side so you can see the step.

As-machined surfaces are enough for many internal and non-critical parts. The finish left by the cutter is usually Ra 1.6–3.2 μm, which is fine for brackets, housings and fixtures that nobody looks at. If you need a specific roughness, put the number on the drawing. A general note like 'smooth' will be interpreted differently by every shop.

Finishing matters when the surface has a job to do: wear resistance, corrosion protection, friction reduction, electrical contact or appearance. Anodizing aluminium gives a hard, corrosion-resistant oxide layer. Electroless nickel adds uniform thickness on complex shapes. Bead blasting and brushing even out tool marks before anodizing. Laser marking needs a minimum character height of 1.5 mm to stay legible.

Tell us the environment the part will see. Outdoor hardware, medical housings and food-contact parts each point to a different finish. We will recommend based on the application rather than on what is easiest to run. If a finish is only cosmetic, say so. It is often cheaper to leave it off.

A useful quote separates material, machining, finishing and inspection. If everything is bundled into one line, you cannot tell which part of the part is expensive. Ask for the breakdown when the number is higher than expected. It is usually one feature, one tolerance or one finish driving the cost, and often that feature is not critical.

Lead time matters as much as price. Our quotation and free DFM analysis come back within 12 hours. Production can start within 24 hours of a confirmed order, and parts typically ship in 3–5 days. We hold a historical late-delivery probability below 2%. Those numbers assume the drawing and model match. When they do not, the first question back to you costs a day.

Check the DFM notes before you approve. They flag thin walls, sharp internal corners, deep holes and features that need a special cutter. Moving one corner radius from 0.5 mm to 1.0 mm can remove an EDM operation. Most DFM feedback is free to act on and cheaper than a rework loop.

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  Ask for a line breakdownMaterial, machining, finish and inspection should be separable.
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  Check the DFM notesSmall geometry changes often remove a whole operation.
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  Confirm the revisionQuote against the model revision you actually intend to build.

Uploads are secure and confidential. We do not share models or drawings outside the quoting and production team. An NDA is available on request if your program requires one before files move. For defense, medical and unreleased consumer products, we sign first and quote second.

We hold ISO 9001:2015, IATF 16949:2016, ISO 13485:2016 and ISO 27001:2022. The information security certificate covers how design data is stored and accessed, which matters when the CAD file is the product. Inspection is 100% before shipment, with raw material checks, in-process monitoring and a final report on request.

If you are not ready to release the full model, send a simplified version with the critical features intact. We can quote on that and refine once the NDA is in place. It is a normal step in automotive and medical programs, and it does not slow the estimate down much.