Square to Rectangle Base Converters – OBS | Hobby Heaven UK

Hobby Heaven Open Basing System

🏆 Square to Rectangle Base Converters

Premium 3D Printed | FDM PLA | Made in the UK 🇬🇧

⚔️ Part of the Open Basing System (OBS) ⚔️

💡 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?

×1

Try Before You Buy

Characters & unique models

×3

Small Units

3-model cavalry groups

×5

Standard Units

5-model cavalry units

×10

Full Regiments

Large units or two squads

×25

Full Army — Best Value

Convert an entire collection

✨ 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

Do I need to remove my models from their original square bases?

No — that's the whole point. Your models stay on their square bases. The square base simply sits inside the converter, which provides the rectangle footprint required by the game.

Will the square base fit securely inside the converter?

Yes. Each converter is precision-engineered for a snug, secure fit. Models won't rock or slide during gameplay. If you have any doubts about fit, message us with your base dimensions and we'll advise before you order.

Can I paint the converters to match my basing?

Absolutely. The PLA surface primes and paints excellently with both spray primer and brush-applied acrylics. Many players texture and paint their converters to create a fully seamless look with their existing bases.

Are these tournament legal for Warhammer: The Old World?

These converters produce the exact rectangle base sizes specified in The Old World rules and are widely accepted at events. We always recommend checking the specific guidelines for your tournament organiser.

Do these work with Hobby Heaven movement trays?

Yes — full OBS compatibility means your converted models drop directly into our matching movement trays with no modifications needed.

I have an unusual base size — can you make a custom converter?

We're always expanding the OBS range based on community requests. Message us with your requirements and we'll do our best to accommodate you or add it to our standard range.

Keywords: square to rectangle base converter, warhammer base converter, the old world base adapter, 3D printed base converter, square base to rectangle, warhammer fantasy bases, rank and flank basing, rebasing solution, no rebase, OBS open basing system, hobby heaven, 20mm square base, 25mm square base, 30mm square base, 40mm square base, 50mm square base, 100mm square base, 50x25 rectangle, 60x30 rectangle, 60x40 rectangle, 75x50 rectangle, 100x50 rectangle, 100x60 rectangle, 150x100 rectangle, cavalry bases, chariot bases, monster bases, war machine bases, tournament bases, warhammer old world, kings of war bases, movement tray compatible, wargaming accessories, miniature basing, tabletop gaming, UK made, painted miniature protection, PLA 3D print, wargaming hobby UK

Item		Price	Qty	Total
		Subtotal	£0.00
		Shipping
		Total

3D Prints - Items tagged as "Obs-converter-intent-shape-change"

Our brands

Net Orders Checkout

Shipping Address

Shipping Methods