O Gauge Parametric Bridge Abutments

🧱 Parametric O-Gauge Modular Masonry Bridge Abutments

O Gauge Track Compatible Custom Bridge Support System

This is a fully parametric, modular masonry abutment system designed for O-gauge layouts.

Inspired by various O gauge bridge supports, this system lets you generate custom stackable bridge abutments with:

• Brick-textured walls
• Modular stacking alignment
• Stepped bridge mounting surface
• Table-mounting tabs with counterbore screw holes
• Fully adjustable heights

Perfect for supporting custom 3D printed bridges, FasTrack bridges, or any 1/4" (6.35 mm) bridge deck.

🧱 What This System Includes

You can generate:

• Base Section
  • Hollow masonry shell
  • Four internal structural corner columns
  • 4 alignment pegs on top
  • 4 receiving sockets on bottom
  • 4 mounting tabs (2 per side)
  • Rounded tab ends
  • Recessed counterbore screw holes
• Riser Sections (2 heights)
  • FasTrack-height riser
  • Tubular-height riser
  • Stackable alignment system
• Top Bridge Mount
  • One-sided stepped deck support
  • Designed for a 6.35 mm bridge deck (adjustable)
  • Brick-textured sides
  • Alignment sockets underneath

🏗 Preconfigured Lionel-Compatible Stack Heights

This system includes preconfigured stack combinations designed to match common Lionel-style trestle heights using:

• 1 Base
• 1 Riser (choose height)
• 1 Top Bridge Mount

You can generate complete abutments that align with:

🔹 Tubular Track Trestle Height (~4.75")

• 1 Base
• 1 Tubular Riser
• 1 Top

🔹 FasTrack Trestle Height (~5.50")

• 1 Base
• 1 FasTrack Riser
• 1 Top

🔹 3D Printed Trestle Height (~6.90")

• 1 Base
• 1 Printed Trestle Riser
• 1 Top

These stack heights were selected to align with traditional Lionel graduated trestle systems and common bridge elevations.

📏 Standard Heights (Default Configuration)

These match common Lionel-style stack combinations:

• Base: 69.85 mm (2.75")
• Riser (FasTrack): 39.37 mm (1.55")
• Riser (Tubular): 20.32 mm (0.80")
• Top Cap: 15.24 mm (0.60")

Pre-configured stacks:

• 4.75" total height
• 5.50" total height
• 7.00" total height

All values are fully adjustable.

⚙️ Fully Adjustable Parameters

📐 Footprint

• WIDTH
• DEPTH

🧱 Brick Pattern

• COURSE_HEIGHT
• BRICK_LENGTH
• MORTAR_DEPTH
• MORTAR_WIDTH

🏗 Shell Construction

• WALL_THICK

🔩 Alignment System

• PEG_SIZE
• PEG_H
• SOCKET_CLEAR
• SOCKET_DEPTH
• PEG_TIP_SHRINK
• PEG_TIP_H

Chamfered peg tips + optional socket lead-in for smooth stacking.

🪜 Bridge Mount Step

• DECK_THICK (bridge deck thickness — default 6.35 mm)
• STEP_IN (how far step extends inward)
• STEP_SIDE (front or back edge)

🪛 Mounting Tabs

• TAB_LENGTH
• TAB_WIDTH
• TAB_THICK
• TAB_Y_SPACING
• TAB_HOLE_D
• TAB_BORE_D
• TAB_BORE_DEPTH

Tabs are rectangular with rounded outer ends and fully integrated into the base for strength.

🖨 Printing Recommendations

• PLA works great.
• 3–4 walls recommended.
• 10–15% infill is sufficient (shell design provides structure).
• No supports required.
• Print base upright as designed.

For snap-fit tuning:

• Adjust SOCKET_CLEAR for your printer tolerance.
• 0.30–0.40 mm works well on most modern machines.

🏗 Use Cases

• Supporting custom 3D printed bridges
• Replacing Lionel plastic abutments
• Creating taller custom spans
• Permanent layout mounting
• Modular height experimentation

Edit: Special thanks to /u/TransportationEng from Reddit for correcting me. These are abutments not piers.