Frequently Asked Questions

Files & format

What file types can I open?

DSTV NC files, usually with the .nc1 extension (sometimes .nc). These are plain-text files following the DSTV standard for structural steel pieces, exported by detailing software such as Tekla Structures, Autodesk Advance Steel, SDS/2, and CAD add-ins for Inventor or SolidWorks. If you are not sure what an NC1 file is, start with What is a DSTV NC1 file?

Which profile types are supported?

All the standard DSTV profile codes: I-sections (I), channels (U), angles (L), plates/flats (B), round tubes (RO), round bars (RU), rectangular/square hollow sections (M), C-profiles (C), and T-sections (T). See the profile types guide for details.

Can I open several parts at once?

Yes. Select multiple .nc1 files in the file dialog (or drag and drop them together) and they all load into the parts list, so you can click through a whole delivery or export batch part by part.

A file will not open or looks wrong. What should I do?

NC1 exporters vary, and some produce non-standard output. First check the file opens as readable text and starts with an ST block. If it still fails or the geometry looks wrong, send us the file with a note about which software exported it — exporter quirks we can reproduce usually get fixed.

Privacy & security

Are my files uploaded to your servers?

No. All parsing and rendering happen locally in your browser. For normal viewing, your file data never leaves your device — it is not uploaded, analyzed server-side, or used for advertising. Details are in the Privacy Policy.

Do I need an account?

Not for viewing. An account is only needed for the Pro subscription, which unlocks editing and export features.

Free vs Pro

What is free, and what is Pro?

Viewing is free: open files, browse 2D face views and the 3D model, inspect holes, contours, and header data. Pro adds professional workflow features — editing hole positions and header fields, exporting corrected NC1 files, and other tools aimed at daily production use.

How do I cancel my subscription?

From the in-app account settings, at any time — cancellation takes effect at the end of the paid period. You can also delete your account entirely from the same place.

Using the viewer

What do the face letters v, o, u, h mean?

They are the DSTV face codes used in hole and marking blocks: v = front/web (Vorderseite), o = top flange (Oben), u = bottom flange (Unten), h = rear (Hinten). The 2D view shows each face as its own drawing, matching how a beam line addresses the part. More in the block codes guide.

Are slotted holes and counterbores shown?

Yes. The parser understands slot length/width extensions on BO lines and counterbore (stepped-hole) definitions, and renders them accordingly in 2D and 3D.

Does it work on tablets and phones?

The viewer runs in any modern browser and works on tablets; a desktop or laptop gives the most comfortable experience for detailed inspection work.

Still stuck?

Check the guides for background on the DSTV format, or contact us — we read everything.