Get a Part Machined Without a Shop

What you actually need to start

One of these: a 3D CAD model (STEP is a widely used data exchange format for 3D CAD (source 1), and any file type can be sent), a 2D drawing as a PDF, a dimensioned sketch on paper, a phone photo with a few measurements written on it, or a new sample part to be measured. The more of those you have, the less the quote has to ask, but any one of them is enough to begin. What file to send covers the formats and what a good print includes.

Then three facts: the material (or "not sure, please advise"), the quantity, and any date you are working against. If you do not know the material, say what the part does and what it fits, and you get a recommendation with the quote rather than a blank form. If you have no CAD at all, get a custom part made walks the idea-to-part route, where the model is built for you, quoted as its own line, and you own the files afterwards.

Route one: an online instant-quote platform

Upload a 3D model and the platform prices it on screen. Xometry’s FAQ says its engine prices parts and generates lead times "instantly based on the 3D geometry of uploaded CAD files" (source 2), and Protolabs says a quote and manufacturing analysis come back "in seconds to hours" (source 4). On speed and lead time a platform fits better when you have a model and need it quickly: Xometry lists a standard lead time of 3-7 business days (source 3), and Protolabs lists machined prototypes as fast as 1 day (source 4).

What a platform takes in is set by its own terms, so read them before you upload a sketch, photo or sample. Protolabs says 2D drawings can be submitted with the 3D model (source 5), and one platform’s help page says it needs a 3D CAD file and cannot work from a picture, 2D drawing or physical replica (source 6). The Xometry comparison sets this route beside the one here. MI CNC Parts vs Xometry vs Protolabs sets out the published terms of two of the largest platforms, with sources.

Route two: a local job shop

A local job shop quotes you directly. Each shop sets its own schedule, its own minimum charge and the work it takes on, so ask about all three before you send the print. If a local shop wants the job and the timing works, use it; the same print, material and quantity go to any route you try.

Route three: send it to a person who quotes, sources, and inspects

This is the model here. You send files or a sketch through the quote form, a real person reads them, and a quote with price, material, and lead time comes back in 24-48 hours, with a free design review of your own design: where a callout may cost more than the part needs or may not work as drawn, the quote says so, and whether to change it is your call. Approve it, and the part gets made to your print. Every part inspected against your print before it ships. If a part doesn’t match the print, it’s remade or credited. Shipping is quoted as its own line, or ships on your carrier account. Reply to the quote email and the same person answers. That is the entire process: no portal, no account, no minimum quantity, and one piece is quoted the same way as fifty.

It suits the engineer at a startup with a design and no floor, the maintenance manager who needs a part and has no drawing, the researcher who needs four of something, and the person building one thing they care about. Rush: 1-2 weeks. Standard: 4-6 weeks (typical). Extended: 6-8 weeks, for jobs that aren’t time-sensitive. How long custom machined parts take explains where the weeks go.

What it costs, and why one piece costs what it does

A custom part’s price comes from the print, and one piece carries all of the setup. Setup is the time from the last part of the previous run to the first good piece of yours, and it happens once per run, so a single piece carries all of it and a larger run divides it (sources 7 and 8). That is arithmetic, not a penalty. CNC machining cost walks through what sets the number (tolerance, quantity, material, geometry, finish, inspection, date), and the quote comes back with the number for your part and a note on what is driving it.

When machining is not the right route

Honesty cuts both ways. If you only need a form to check fit and feel, a 3D-printed part from a local library, makerspace or print service may do. A flat bracket with no critical features may suit a laser-cut part better than a milled one. A standard hardware item is usually simpler to buy from a catalog than to have made. Machining is the answer when the part has to be a specific metal or engineering plastic and hold the dimensions on the print, which is the moment to send a file.

Sources

All accessed 4 October 2026. Where a figure here differs from your print, the print governs. Platform terms change; if a line here is out of date, the platform’s own page is the authority.

1. Wikipedia, "ISO 10303-21", en.wikipedia.org/wiki/ISO_10303-21, last edited 29 July 2026 (the STEP file as a widely used data exchange form).

2. Xometry, "Answers to the Most Frequently Asked Questions About Xometry", xometry.com/resources/blog/answers-to-most-frequently-asked-questions/, updated 26 August 2026 (prices parts and generates lead times instantly from the 3D geometry of uploaded CAD files).

3. Xometry, "Custom Online CNC Machining Services", xometry.com/capabilities/cnc-machining-service/, no date shown on the page (standard lead time of 3-7 business days).

4. Protolabs, "Online CNC Machining Service", protolabs.com/services/cnc-machining/, no date shown on the page (a quote and manufacturing analysis in seconds to hours; machined prototypes and production parts in as fast as 1 day).

5. Protolabs, "Digital Manufacturing FAQs", protolabs.com/resources/faqs/, no date shown on the page (2D drawings can be submitted with your 3D CAD file).

6. Fictiv, "Can you design a part I need?", fictiv.com/help/getting-started/can-you-design-a-part-i-need, updated 25 July 2025 (cannot produce a part from a picture, 2D drawing or physical replica; a 3D CAD file is required).

7. Mike Lynch, "The Effect of Lot Size on Productivity", Modern Machine Shop, 21 December 2017, mmsonline.com/articles/the-effect-of-lot-size-on-productivity (setup defined as the period from the last part of the previous run to the first good workpiece of the next; it is a larger share of a small lot).

8. Wikipedia, "Average fixed cost", en.wikipedia.org/wiki/Average_fixed_cost, last edited 29 July 2026 (fixed cost divided by quantity; it falls as output rises).