Square to Rectangle Bases Size Converters 3d Print Full Range
Hobby Heaven Open Basing System
🏆 Square to Rectangle Base Converters
Premium 3D Printed | FDM PLA | Made in the UK 🇬🇧
💡 NO REBASING REQUIRED — Your models stay on their original bases. 💡
🔄 What Are Square to Rectangle Base Converters?
These precision FDM 3D printed adapters let you place any square-based miniature directly onto a rectangle base — no glue, no damage, no permanent changes. Perfect for players bringing classic square-based Warhammer Fantasy armies into Warhammer: The Old World, Kings of War, or any rank-and-flank system using rectangular bases. Add the converter before the game, remove it after — your models never change.
🎮 Why Do You Need These Converters?
❌ The Challenge
Classic Warhammer Fantasy armies were built on square bases. Games like The Old World require rectangle bases for cavalry, chariots, and monsters — leaving players with a difficult choice: rebase everything (costly and risky) or stop using beloved painted models. Neither is acceptable.
✅ Our Solution
Drop your square-based model into the converter. It sits precisely, holds securely, and the whole thing is fully reversible. Switch back to your old game in seconds. Your miniatures are never touched, never damaged, never permanently changed.
🔧 How It Works — 3 Simple Steps
Step 1 — Choose Your Size
Select the converter matching your model's current square base and your target rectangle output.
Step 2 — Place Your Model
Drop the square-based model into the converter. No tools, no glue, no hassle — precision fit holds it firmly.
Step 3 — Optionally Paint
PLA takes paint beautifully. Match your existing basing style for a fully seamless, professional result.
Step 4 — Game On!
Your models are ready on perfect rectangle bases. Remove the converter after the game in seconds.
📏 Complete Size Guide
| Input Square Base | Output Rectangle Base | Typical Use — TOW / Rank & Flank | Available Pack Sizes |
|---|---|---|---|
| 20mm Square | 50×25mm Rectangle | Light cavalry, skirmish riders, wolf riders | ×1, ×3, ×5, ×10, ×25 |
| 20mm Square | 60×30mm Rectangle | Standard cavalry mounts, mounted heroes | ×1, ×3, ×5, ×10, ×25 |
| 20mm Square | 60×40mm Rectangle | Heavy cavalry, armoured horses | ×1, ×3 |
| 25mm Square | 50×25mm Rectangle | Light cavalry, fast riders | ×1, ×3, ×5, ×10, ×25 |
| 25mm Square | 60×30mm Rectangle | Standard cavalry, knights | ×1, ×3, ×5, ×10, ×25 |
| 25mm Square | 60×40mm Rectangle | Heavy cavalry, barded mounts | ×1, ×3 |
| 30mm Square | 60×30mm Rectangle | Cavalry characters, command models | ×1, ×3, ×5, ×10, ×25 |
| 30mm Square | 60×40mm Rectangle | Ogre cavalry, large mounts | ×1, ×3 |
| 30mm Square | 75×50mm Rectangle | Monstrous cavalry, war beasts | ×1, ×3 |
| 40mm Square | 60×40mm Rectangle | Elite cavalry, fully armoured knights | ×1, ×3, ×5 |
| 40mm Square | 75×50mm Rectangle | Monstrous cavalry, dragon riders | ×1, ×3, ×5 |
| 40mm Square | 100×50mm Rectangle | Chariots, war machines with crew | ×1, ×3, ×5 |
| 40mm Square | 100×60mm Rectangle | Large chariots, heavy war machines | ×1, ×3, ×5 |
| 50mm Square | 75×50mm Rectangle | Large cavalry mounts, wyvern riders | ×1, ×3, ×5 |
| 50mm Square | 100×50mm Rectangle | Chariots, siege weapon bases | ×1, ×3, ×5 |
| 50mm Square | 100×60mm Rectangle | Large monsters on chariot-style bases | ×1, ×3, ×5 |
| 50mm Square | 150×100mm Rectangle | Massive monsters, titans, centrepiece models | ×1 |
| 100mm Square | 150×100mm Rectangle | Giants, large monsters, massive war engines | ×1 |
🔍 Don't see your size? Message us — we're constantly expanding the OBS range based on community feedback.
🛒 Which Pack Size Is Right for You?
✨ Key Benefits
🔄 Fully Reversible
Switch back to square bases for your old game any time. Remove the converter in seconds — no permanent changes, ever.
🛡️ Model Protection
No scraping, no cutting, no solvents. Your painted miniatures are completely safe throughout the process.
🎨 Fully Paintable
PLA surface accepts primer and acrylics perfectly. Match your existing basing theme for a seamless, natural look.
💰 Cost-Effective
A fraction of the time and cost of full rebasing. Bulk packs deliver excellent value for whole units or armies.
🎯 Tournament Legal
Converts to exact official rectangle sizes. Widely accepted at events — always check your specific organiser's guidelines.
🧩 OBS Compatible
Full compatibility with Hobby Heaven movement trays, display bases, and every component in the Open Basing System.
🧩 Part of the Open Basing System (OBS)
These converters integrate seamlessly into the Hobby Heaven OBS ecosystem — a comprehensive range built so every component works perfectly with every other.
🔄 Base Converters
All shapes & sizes
📋 Movement Trays
For all converter sizes
🏆 Display Bases
Showcase your models
📐 Standard Bases
All game-required sizes
🎯 Perfect For
⚔️ Returning Warhammer Players
Classic square-based Fantasy army sitting in a box? Start playing The Old World right away — zero rebasing required.
🎲 Multi-System Players
Play Age of Sigmar and The Old World with the same models. Add converters for TOW, remove them for AoS. One collection, all games.
🏅 Tournament Players
Need to meet event base size requirements fast? These converters get your army tournament-ready with no prep time at all.
🎨 Painters & Collectors
Protect your carefully painted miniatures from any risk of damage. Your models stay exactly as you made them.
🏭 Production Details
| Material | PLA — FDM 3D printed, high-quality |
| Finish | Paintable surface — accepts primer, acrylic, and enamel paints |
| Production Time | 3 working days (made to order) |
| Manufactured In | United Kingdom 🇬🇧 |
| Packaging | Protective packaging to prevent transit damage |
| Shipping | Tracked shipping available |
| OBS Compatible | Yes — works with all Hobby Heaven movement trays and accessories |
💯 Our Compatibility Guarantee
If your converter isn't compatible with your bases, we'll provide a free replacement in the correct size. No questions asked — just message us.
❓ Frequently Asked Questions
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