From a site sketch to a CNC-ready DXF: cladding panel drawings without the retyping

Every cladding job ends up with panels that weren't on the shop drawings. A make-up panel at a window head. A replacement for one damaged in transit. A corner that came out different on site. The installer measures it, sketches it on whatever is to hand, and sends a photo. What happens next decides whether the panel that comes off the router fits.

Why do replacement panels go wrong?

Not usually because anyone measured badly. They go wrong in the hand-offs.

The sketch travels as a photo in a text thread. Someone in the office reads it, rings site to ask whether that is a 7 or a 1, draws it up in CAD, and sends a file to the factory. Each of those steps is a person retyping a number another person wrote. Each is a chance to get one wrong — and a wrongly cut composite panel is a panel you pay for twice.

The fix is not to measure more carefully. It is to stop retyping the numbers.

How do you get from a site sketch to a CNC-ready DXF?

Here is the flow, step by step, as it works in Subino's panel drawings.

1. Sketch the panel on site, as you do now. Finished face sizes, written clearly. A page can carry several panels.
2. Photograph the sketch on a phone. One read takes up to eight photos, so the whole sheet of sketches goes in at once (photograph the sketch).
3. Let the dimensions be read, not measured. AI reads the figures written on the sketch. It never measures the photo. Anything it can't make out comes back blank and is listed, so nobody builds on a guess.
4. Check every figure against the sketch. The drawing redraws as the numbers are typed — the finished face, the cut blank around it, and a 3D view of the folded tray (check it, confirm it, see it folded).
5. Confirm the panel. One Confirm records who signed it off and when.
6. The office downloads the DXF. One confirmed panel, one file, ready for the CNC (a CNC-ready DXF).
7. Change it, and it starts again. Change a dimension later and the panel goes back to draft as a new revision, so the old file can't be mistaken for the new one.

What makes a good site sketch?

The reading is only as good as what is written. None of this is new to an installer, but it is worth putting on a card in the ute:

• One panel, one box. Several panels on a page is fine; keep each one's figures inside its own outline.
• Finished face sizes. Write the size the panel should be on the wall. The blank and the returns are worked out from that, so nobody has to add them in their head.
• Write every figure clearly. A 1 and a 7, a 0 and a 6 — the classics. A clear figure is read; an unclear one comes back blank for someone to type.
• Measure a notch or a cut-out from a named edge. "From the left, from the top" beats an arrow that could point either way.
• Label it. A panel number and where it goes, so the file that comes out the other end can be matched to the opening.
• Write down what isn't a dimension. Material, colour and anything odd about the opening — those are notes for the office, not numbers for the drawing.

A sketch like that is quick to check and quick to confirm. A rushed one still works — it just comes back with more blanks to fill in.

What's actually in the DXF?

A DXF is only useful if the person at the router can trust what each line means. Subino's file keeps the three kinds of line apart.

The file is in millimetres, one panel per file, and written as R12 so an older CAM package on the factory PC can open it. The millimetres are written into the file's header, its notes, the sheet title and the filename — so nobody has to guess the units.

DXF is the documented interchange format CAM software reads; DWG is Autodesk's closed format. That is why the output is DXF.

Why read the dimensions instead of measuring the photo?

Because a photo of a sketch has no scale. The paper is curled, the phone is at an angle, and the sketch was never drawn to scale in the first place. Any tool that measures the picture is guessing.

The figures written on the sketch are the measurement — the installer took them with a tape on the actual opening. So that is what gets read. When a figure can't be read, the honest answer is a blank, not a best guess, and a blank stops the panel being confirmed until someone types the number in.

That rule is the whole design: the panel can't move forward on a number nobody has checked.

What shapes can it draw today?

Rectangles, L-shapes (one corner cut away) and panels with one notch. That covers most replacement and make-up panels on a cladding job. Anything else is flagged for a drafter in CAD — never forced into a rectangle.

That limit is deliberate. A tool that forces an odd shape into the nearest rectangle gives you a file that cuts perfectly and fits nowhere.

Has the file been tested on a real CNC?

Yes — through the CNC software in our own cladding business, before the panel drawings page went up. Check a first panel with your own fabricator too: every shop's machine and tooling are set up a little differently.

Who signs off a panel before it's cut?

The people closest to it. The crew photograph the sketch, check the numbers and confirm the panel from their phone. Downloading the DXF sits with the office, behind its own permission, so the file that reaches the router has always been confirmed first. Because roles are enforced in the database, not by hiding a button, that order can't be skipped by accident (permissions in the database).

How does it fit with the rest of the job?

A panel drawing belongs to a job like everything else — the same job that started as a tender, was priced on the cost sheet and is now being built. If you hold panel material in the factory, the factory stock side tracks what is in the yard and puts the cost of what you issue on that job's budget.

That is the idea behind Subino as a whole: one system for the job, entered once. Panel drawings are part of the Pro and Premium plans — pricing has the detail, and the panel drawings page shows the whole flow on a demo job.

If you want to see a real sketch turn into a drawing and a file your CNC can cut, book a 15-minute demo and bring a photo of one.