The most common follow-up question on a new enquiry isn't about price, it's about format. Here's what I need, what I can work with and what you can skip.
The most important thing first: I'd rather have a clean hand sketch with dimensions than a poor CAD file. I'm a development engineer, drawing is part of my job – turning a sketch into a production file isn't a special case for me, it's the norm. Everything else here is a shortcut, not a requirement.
The formats, briefly explained
The standard for panel milling. Contours, holes, pocket outlines – anything flat goes straight into my CAM with it. If you have the choice, send DXF.
As soon as a part has steps, different depths or a 3D surface, STEP is the right format. It's neutral, every CAD program can export it, and I can derive dimensions from it instead of guessing them.
Works too. But I convert it to DXF anyway, so skip the extra step if you can export both.
The typical route out of Illustrator, Inkscape or Affinity. Perfectly fine for lettering, logos and signs. Two conditions: text must be converted to paths, and you need to give me a reference length – SVG has no reliable unit, and a millimetre in a graphics program isn't automatically a millimetre in the workshop.
There are two kinds of PDF: a vector PDF from a CAD or graphics program, which I can use. A scanned or photographed PDF is an image – that's a drawing to look at, not a file to mill. Even so, as a dimensioned drawing alongside the DXF, a PDF is worth its weight in gold, because it shows me which dimensions matter to you.
Not millable, but usable as a template. I trace the contour – that takes time, and it appears in the quote. For simple outlines it's a manageable item; for a detailed logo it isn't.
Comes from the 3D printing world and describes the surface as a triangle mesh. It's the wrong format for milling 2D contours, because a straight edge in it is no longer straight but broken up into facets. If you have STEP, use STEP.
The five mistakes I see most often
- Open contours. What looks like a closed rectangle is often four separate lines with tiny gaps at the corners. The CAM can't create a toolpath from that. Most CAD programs have a function like “join” or “close polyline” for this.
- Duplicate lines. Two identical contours on top of each other – usually created by copying. The result would be every edge being milled twice. I'll find it, it just costs time.
- Text as text. If the lettering isn't converted to paths, the result depends on which font is installed on my computer. Convert it first, and it stays exactly as you designed it.
- Unclear scale. Millimetres, centimetres, inches. Just add one dimension in your email: “outer edge 400 mm long”. That settles the question.
- Sharp inside corners. The cutter is round, so an inside corner will never be sharp. That's not a file error but a design decision – there's a separate article on it.
What I need to know besides the file
Geometry alone isn't an order. With these five details, I can quote in one go without asking three times:
- Material and sheet thickness – or the question to me of what's suitable. Both are fine.
- Quantity. Even if it's one. Batch size 1 is explicitly normal for me.
- Which side is the visible side and how accurate it needs to be. “Visible front” and “a jig that just has to work” are two different jobs.
- Preferred date. So I can tell you whether it's realistic.
- Collection or shipping. With large panels, this makes more difference to the price than the milling.
Then we start with the sketch. I turn a hand drawing into a production file and send you a drawing for approval beforehand, so we both have the same part in mind. That's exactly why joiners, sign makers and makers come to me instead of a panel-cutting portal.
Send a sketch and get a quote!
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