For a flat laser-cut part, send a DXF. For a part that will be bent, send a STEP model as well, so the shop can see the folded shape and build the flat pattern to suit its own tooling.
That's the rule we'd give anyone. But plenty of good jobs start with a DWG from an architect, a PDF from a client, or a photo of a broken bracket, and all of those can become cut parts. The file mainly decides how much interpretation the shop does before cutting. Below is what each format is good for, what goes wrong with it, and what to send when you only have a picture.
The quick answer, by situation
| Your situation | Best file to send | Also helpful |
|---|---|---|
| Flat part, no bends | DXF at 1:1 in millimetres | PDF if any tolerances matter |
| Part with bends | STEP of the finished part | DXF flat pattern, PDF drawing |
| Welded assembly | STEP of the assembly | PDF assembly drawing with weld notes |
| Architect or AutoCAD drawing | DWG or DXF | PDF showing which parts you want |
| No CAD at all | Dimensioned sketch or PDF | Photos with a tape measure in shot |
DXF and DWG: the 2D files a laser runs on
DXF
DXF is a 2D vector format. Nearly every CAD program exports it, and nearly every cutting system reads it. Each line in a DXF becomes a path for the beam, which is both why it's the ideal format and why a messy one causes trouble.
A good DXF is drawn at full size in millimetres, has closed outlines, and contains nothing that shouldn't be cut. Dimensions, borders, and notes all need to come out. We've written a full walkthrough on how to prepare a DXF file for laser cutting, so we won't repeat it here.
What a DXF can't easily tell us: the material, the thickness, which way a flange bends, or which face is the show side. Put those in the quote or a short PDF.
DWG
DWG is AutoCAD's native format. As far as cutting goes, it behaves much like a DXF: 2D geometry that can be read straight into the cutting software.
The difference is what tends to come with it. DWGs are often working drawings, with several views, hatching, dimension layers, a title block, and sometimes a whole building plan around the one bracket you want. That's fine to send, as long as it's clear which shape is the part. A quick note like "cut the plate on layer PLATE-01 only" saves a phone call.
STEP: best for anything that bends
A STEP file is a 3D solid model. It's the most useful file you can send for a bent or welded part, because it shows the finished shape without any guesswork.
Here's why that matters. The flat pattern of a bent part depends on the bend radius, the material, and the tooling on the press brake. If you send only a flat DXF that your CAD unfolded with its own default settings, the flanges may come out a little long or short once it's bent on a different machine. With a STEP of the finished part, the shop can unfold it using values that match its brakes. Our post on flat patterns vs 3D models covers this in more detail.
If you work in SolidWorks, Inventor, Fusion, Onshape, or similar, export STEP (AP203 or AP214 are both widely read). Native files like SLDPRT aren't always readable by another shop's software, so convert them before you send.
PDF: great as a drawing, weaker as cut geometry
A PDF is how most people share drawings, and it's the right place for the information a DXF can't carry: dimensions, tolerances, hole callouts, finish, material, and quantity.
Can a laser be programmed from a PDF? Sometimes. If the PDF was exported from CAD as vectors, the geometry can occasionally be extracted. If it's a scan, someone will have to redraw the part from the dimensions. That's doable for a simple plate, but it's an extra step, and every redraw is a chance for an assumption to creep in.
Photos, sketches, and broken parts
You don't need CAD to get a part made. A clear sketch with dimensions, or a photo of the part lying on a flat surface with a tape measure next to it, is enough to start a quote.
What helps most:
- Overall length, width, and thickness, in millimetres
- Hole sizes and their positions from one edge
- Bend angles and which side they go
- The material, or what the old part was made of
- How many you need
The shop draws it up from there. For anything that has to fit something else, ask to see that drawing and check it before the metal is cut. Our guide to getting a metal part made from a sketch or photo goes through it step by step.
Illustrator, SVG, and CorelDRAW files
These come up a lot for signs and decorative screens. They're vector files, so the geometry is usually good, but they're built for print, not for cutting. Common problems are outlines that are actually thick strokes, text that hasn't been converted to curves, and artwork that isn't at real-world size.
Our quote form takes DXF, DWG, STEP, PDF, or a photo, so export the artwork as a DXF (most design programs can) or as a vector PDF at 1:1 scale. Convert text to outlines first.
Sending files to us
Upload the file on the quote form with the material, thickness, and quantity. The form takes DXF, DWG, STEP, PDF, or a photo up to 10 MB. Large STEP assemblies sometimes go over that, so email them to ctrlcutsa@gmail.com instead.
Not sure your file is suitable? Send what you have and say so in the notes. Start a laser cutting quote, or read more about our laser cutting service first.