ILX Suite · Document Assembly

Turn a folder of calcs into a sealed submittal.

ILX PDF is the assembly bench for your calculation package. Combine and order source documents, build bookmarks and a table of contents automatically, number every page, stamp and watermark the set, place your seal, and export an archival PDF — so the submittal looks as rigorous as the engineering behind it.

The last mile of every engineering deliverable

A finished design is only as good as the package that documents it. Yet assembling a submittal — merging calc sheets, reference excerpts, sketches, and analysis output into one coherent, navigable, consistently numbered document — is slow, error-prone manual work. ILX PDF turns that last mile into a repeatable operation built specifically for engineering deliverables.

Calculation output from ILX Structures, ILX Connection, and ILX Concrete flows straight into a package, but ILX PDF works just as well with any source document. Define the order once, and bookmarks, the table of contents, page numbering, and project stamps regenerate automatically every time the package is rebuilt — so a late revision to one calc does not mean re-numbering the whole set by hand.

What ILX PDF does

🧩

Combine & reorder

Merge multiple PDFs and page ranges into one package, then drag to reorder, insert, split, or remove pages.

🔖

Bookmarks & TOC

Auto-generate a nested bookmark tree and a printed table of contents from your section structure.

🔢

Page & Bates numbering

Continuous page numbering and sequential Bates-style stamps applied across the whole set in one pass.

🏷️

Headers, footers & stamps

Project, client, date, and revision stamps placed consistently on every page from a reusable template.

💧

Watermarks

Draft, preliminary, or confidential watermarks applied or removed across the package at any time.

✍️

Markup & redlines

Text notes, callouts, highlights, shapes, and measurements for review and back-check cycles.

🛡️

Seal placement

Position a professional engineer seal and signature block; lock the final set against further change.

🗄️

Archival export

Export to the PDF/A archival standard for durable records and clean submittals.

⚙️

Batch & templates

Save package templates and apply numbering, stamps, and structure to many sets at once.

Built for the way calc packages are actually produced

The formats behind reliable submittals

AreaBasisWhat it provides
Document formatPortable Document Format (ISO 32000)Page model, bookmarks, annotations, and metadata handled to the published specification
ArchivingPDF/A (ISO 19005)Self-contained, long-term-stable output for records and submittals
Sealing practiceJurisdictional professional engineering seal requirementsPlacement of seal, signature, and date consistent with the engineer of record's obligations
Suite integrationILX Structures · Connections · ConcreteDirect import of calculation output into an assembled package

Format and archival standards are referenced by their issuing organizations for interoperability. Seal and signature requirements vary by jurisdiction and remain the responsibility of the licensed engineer; ILX PDF provides placement and document-integrity tools, not legal or licensing advice.

How it fits your process

1. Gather. Pull in calc output from the ILX Suite and any other source PDFs.

2. Organize. Order pages into sections; bookmarks and the table of contents build themselves.

3. Brand. Apply numbering, stamps, headers, and watermarks from a reusable template.

4. Review. Mark up, redline, and back-check; revise source calcs and rebuild without re-numbering by hand.

5. Seal & archive. Place the seal, lock the set, and export an archival PDF/A submittal.

Frequently asked questions

What is ILX PDF for?

It assembles engineering calculation packages — combining and ordering documents, building bookmarks and a table of contents, numbering and stamping pages, placing seals, and exporting an archival submittal.

Does it work with documents from outside the ILX Suite?

Yes. It imports calculation output directly from ILX Structures, Connections, and Concrete, and also assembles any other source PDFs you bring in.

Can numbering and bookmarks survive a late revision?

That is the point. Bookmarks, the table of contents, and page numbering are generated from the package structure, so they regenerate automatically when you swap in a revised calc — no manual renumbering.

Does it support sealing and locking the final set?

You can position a professional seal and signature block and lock the completed package to protect submittal integrity. Seal and licensing requirements vary by jurisdiction and remain the engineer's responsibility.

What output format does it produce?

Standard PDF for working sets and archival PDF/A (ISO 19005) for records and submittals.

ILX PDF — Complete Documentation

Version 1.4  ·  15 Chapters  ·  © 2026 ILX Studio, LLC

Contact Support
1Introduction

ILX PDF is a professional Windows PDF application for viewing, editing, organizing, signing, certifying, and archiving PDF documents. Designed for engineering firms, legal offices, and technical professionals — with a clean UI and no subscription fees.

Signing is the Centerpiece

ILX PDF’s signing engine (powered by pyHanko, MIT license) supports more scenarios than most commercial competitors: approval and certifying signatures, all four PAdES baseline profiles (B-B, B-T, B-LT, B-LTA), RFC 3161 timestamps, LTV (Long-Term Validation) with embedded OCSP/CRL data, and PKCS#11 HSM / USB token / smartcard signing.

Recommended First Workflow

  1. Open the PDF and confirm page count, bookmarks, and document metadata.
  2. Apply annotations or edits as needed.
  3. Run OCR if the document is scanned and needs searchable text.
  4. Apply redactions only after review and save a separate redacted copy.
  5. Certify or sign the final issue version.
  6. Add timestamps and LTV data when long-term validation is required.
  7. Archive the signed PDF with the project record.

ILX PDF main window with a structural calculation report open, showing the PDF viewer, sidebar with page thumbnails, and the Signatures panel with a validated certifying signature.

img/pdf_main_interface.png — screenshot coming soon
2System Requirements
RequirementMinimumRecommended
OSWindows 10 (64-bit)Windows 11
CPU2-core4-core
RAM4 GB8 GB
Storage500 MB free2 GB
Display1920 × 10802560 × 1440
OCR requires an additional 200 MB for Tesseract language data files (downloaded on first OCR use).
3Installation & Licensing
  1. Download ILX-PDF-Setup.exe from the ILX Studio website.
  2. Run the installer. A Start Menu entry is registered. .pdf file association is optional (prompted during installation).
  3. On first launch, sign in with your ILX Studio account to activate your seat.

Your seat is managed through the unified license.ilxstudio.com portal. Sign in on one machine at a time. Sign out via File → Account → Sign Out to release your seat. Updates are Ed25519-signed and verified before applying.

4Getting Started

Ctrl+O or drag a PDF file onto the application window. Multiple PDFs can be open simultaneously as document tabs. Password-protected PDFs: you are prompted for the password (not stored). Recent files appear on the Start page.

5Viewing PDFs

Navigation

ActionControl
Next / previous pagePage Down / Page Up
Go to pageCtrl+G → type page number
Zoom in / outCtrl++ / Ctrl+- or scroll
Fit to widthCtrl+W
Full screenF11
Find textCtrl+F

Sidebar Panels

PanelContents
Pages (Ctrl+1)Page thumbnails — drag to reorder, right-click to delete or extract
Bookmarks (Ctrl+2)Document outline / table of contents (clickable)
Signatures (Ctrl+3)List of all signatures with validation status
6Editing PDFs

ILX PDF supports non-destructive editing — changes are added as an incremental update layer, preserving the original content.

Annotation Tools

ToolShortcutDescription
Sticky noteNPop-up comment anchored to a point
HighlightHYellow (or custom color) text highlight
UnderlineUUnderline text
StrikethroughSStrike through text
Freehand drawDFree-form ink annotation
RectangleRRectangle annotation (filled or outline)
ArrowAArrow with optional label
Text boxTFree-floating text box
StampApply APPROVED, VOID, FOR REVIEW, etc.

The annotation toolbar active over a structural calculation report, with a yellow highlight over a key equation, a sticky note open with a reviewer comment, and a red rectangle flagging a section for revision.

img/pdf_annotation_tools.png — screenshot coming soon
7Creating PDFs

New PDF from Blank

File → New PDF — set page size (Letter, Legal, A4, A3, or custom), orientation, color profile (RGB or CMYK), and initial page count.

New PDF from Images

File → New PDF from Images — select one or more image files (PNG, JPEG, TIFF, BMP). Each image becomes one page. A dialog lets you set the page size per image.

PDF from Print

Install the ILX PDF Printer (included in the installer) as a system printer. Print from any application → select “ILX PDF Printer” → choose a save location. The resulting PDF is fully text-searchable.

8Digital Signatures & Certification

Signature Types

TypeDescriptionUse Case
Approval signatureYou approve the document as-isOne of many reviewers signing off
Certifying signatureAuthor certifies; sets permission levelFirst signature; PE certification

PE Certification Workflow

  1. Open the PDF.
  2. Sign → Certify Document.
  3. Select a signature field or click to create one on the page.
  4. Select your certificate (Windows Store, PKCS#12 file, PKCS#11 hardware token, or smart card/CAC).
  5. Set Permissions: no changes / form fill + annotations / form fill only.
  6. Add optional reason (e.g. “Reviewed and approved for construction”) and location.
  7. Click Certify.

Timestamps & Long-Term Validation (LTV)

Configure an RFC 3161 TSA (timestamp authority) in Settings → Signing → Timestamp Server to prove the document was signed at a specific time. Sign → Add LTV embeds OCSP responses and CRL data for all certificates in the chain — signatures remain verifiable even after certificates expire.

The Signatures panel showing a certified signature with “Valid – ETSI EN 319 102-1 B-LTA” status, the signer’s name, timestamp, and a green validation chain icon.

img/pdf_signature_panel.png — screenshot coming soon
9OCR — Searchable PDFs

Running OCR

  1. Open the scanned PDF.
  2. Tools → OCR → Make Searchable.
  3. Select pages to process and language (English default).
  4. Click Run OCR. A progress bar shows page-by-page status.
  5. Save the file — the original image is preserved; the OCR text layer is added behind it.

OCR Accuracy

Best results require 300 DPI or higher scan resolution and high-contrast (dark text on white). ILX PDF automatically deskews pages before OCR processing. Switch to the full LSTM model in Settings → OCR → Engine → LSTM for unusual text.

10Merging, Splitting & Organizing

Merging PDFs

File → Merge PDFs — add files, reorder by dragging, choose which pages from each file to include, then click Merge. A new combined PDF opens (save with Ctrl+S).

Splitting a PDF

File → Split PDF — by page range, by bookmarks (each top-level bookmark becomes a separate file), or every N pages.

Reordering & Extracting Pages

Drag page thumbnails in the Pages sidebar to reorder. Right-click one or more thumbnails → Extract Selected Pages to save a new PDF with only those pages.

The Merge PDFs dialog with four structural calculation PDFs listed (with page counts), a drag-handle interface for reordering, and a page-range selector open on one of the files.

img/pdf_merge_dialog.png — screenshot coming soon
11Redaction
Redaction permanently removes content from a PDF — it cannot be undone after saving. Always work on a copy.

Redaction Workflow

  1. Tools → Redact → Mark for Redaction. Click and drag to mark areas (shown as red rectangles).
  2. Review all marked areas.
  3. Tools → Redact → Apply Redactions — permanently burns black boxes over marked areas and removes underlying content.
  4. Save the file under a new name.

Text-Search Redaction

Tools → Redact → Redact by Search — enter a search term (e.g. a name or account number) and ILX PDF marks all occurrences automatically. Review marks before applying.

12Forms

ILX PDF can fill, create, and export PDF forms (AcroForms — the standard PDF form type). Click any field to fill it: text fields, checkboxes/radio buttons, dropdown lists, and signature fields. Tab moves between fields in tab order.

Flattening & Exporting

Tools → Forms → Flatten converts all form field values into static page content — fields can no longer be edited. Tools → Forms → Export Data → CSV exports all field names and values to a CSV file.

13Export & Conversion

Export Pages as Images

File → Export → Pages as Images — format: PNG, JPEG, TIFF; resolution: 72, 150, 300, 600 DPI; color: RGB, Grayscale, or B&W; page range: all or selection.

Export to PDF/A

File → Export → PDF/A — converts to PDF/A-1b or PDF/A-2b (ISO 19005 archival format). All fonts are embedded and color spaces are normalized. Required for some regulatory and court filings.

Export to Text

File → Export → Plain Text — extracts all text content from the PDF. Formatting is not preserved.

14Settings & Themes
SettingLocationOptions / Notes
ThemeSettings → Display → ThemeDark (default) / Light / High-Contrast
Default page viewSettings → ViewDefault zoom and layout on first open
Default certificate sourceSettings → SigningWindows Store / PKCS#12 / Hardware token
Timestamp server (TSA)Settings → SigningPublic or enterprise TSA URL
Signature appearanceSettings → SigningHandwritten name, logo, date format
Temp files%LOCALAPPDATA%\ILX Studio\PDF\Temp\

The Settings → Signing panel showing the certificate source dropdown, the TSA URL field, a sample signature appearance preview with a company logo, and the PAdES profile selector.

img/pdf_signing_settings.png — screenshot coming soon
15Troubleshooting

PDF Renders Slowly or Shows Black Pages

Enable View → High-Quality Rendering → Lazy Mode for large PDFs. If pages show black, go to Settings → Display → Renderer → Software to fall back to CPU rendering.

Signature Validation Shows “Unknown — Certificate Not Trusted”

Import the signer’s root certificate into Windows Settings → Manage Computer Certificates → Trusted Root Certification Authorities.

OCR Produces Garbled Text

Re-scan at 300 DPI or higher. Switch to the LSTM model: Settings → OCR → Engine → LSTM.

Merge Produces an Oversized File

PDF merging preserves all embedded fonts. If source files embed the same font multiple times, run File → Optimize PDF after merging to deduplicate embedded resources.

A–HAppendices

A. Manual Conventions

ConventionMeaning
Bold textButton, ribbon tab, menu item, panel name, or UI label
MonospaceCommand, file extension, keyboard shortcut, path, or literal value
✓ / ✗ / ⚠Pass, fail, and warning status indicators

B. File Management

Keep working copies separate from final signed/certified PDFs. Use version-controlled project folders. Never work directly from email attachments or temporary download folders.

C. Document Integrity Note

PDF editing, redaction, certification, and signing can have legal or contractual consequences. Understand your organization’s document control procedures before certifying, redacting, or issuing documents. Always save an unsigned working copy before applying final signatures or irreversible redactions.

D. Accessibility

Dark, Light, and High-Contrast themes. Increase UI text scale in Settings → Display.

E. Support & Logs

Logs at %LOCALAPPDATA%\ILX Studio\PDF\Logs\. Contact support@ilxstudio.com with product version, Windows version, document file (if permitted), and steps to reproduce.

F. Glossary

TermMeaning
PAdESPDF Advanced Electronic Signatures — ETSI EN 319 102-1 signature profiles (B-B, B-T, B-LT, B-LTA).
LTVLong-Term Validation — embedding OCSP responses and CRL data so signatures remain verifiable after certificate expiry.
TSATime Stamp Authority — an RFC 3161 trusted third party that time-stamps signatures.
PDF/AISO 19005 archival PDF format with embedded fonts and normalized color spaces.
OCROptical Character Recognition — converting raster-image text to searchable text.

G. Revision History

VersionDateNotes
1.02026Initial manual draft.
1.12026Expanded professional-use guidance, QA, accessibility, and glossary content.

H. PDF Issuance Checklist

  • Correct file, page count, and revision.
  • Bookmarks, page labels, and attachments if required.
  • OCR layer accuracy for scanned documents.
  • Redactions are applied and verified in a new file.
  • Signature field placement and appearance.
  • Certificate source, timestamp server, and LTV settings.
  • Final signed copy is archived separately from the editable working copy.

Assemble your next package the easy way

Request a demo and we will build a sealed, bookmarked, numbered calc package from start to finish.

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