Beginner
≈ 3 hSuggested range1 h 45 min – 4 h 30 min
Official LEGO® image · © LEGO Group and/or the respective rights holders. Source: LEGO Italy ↗
Technic · SET 42201
Deep-Sea Research Submarine
A little Technic submarine focuses on propellers and a recovery arm.
- Pieces
- 413
- Release year
- 2025
- Theme
- Technic
- Set number
- 42201
- LEGO recommended age
- 9+
- LEGO retail price · Italy
- 39.99 €
Available at LEGO Italy when checked on 23 October 2026. Availability can change. Check the store for the latest information.
Retail price reported by the LEGO source for the stated market. Check the store for current price and availability; this does not establish the launch price. LEGO ↗ · Reference checked on 23 October 2026
Official English name verified at: LEGO English catalogue ↗ · Checked on 24 October 2026.
TIME TO BUILD
How long does it take to build Deep-Sea Research Submarine?
A starting point for planning your build. Times for each experience level are editorial estimates, not measurements submitted by HowLongToBuild users.
Editorial model estimate · no verified measured building time
Intermediate
≈ 2 hSuggested range1 h 15 min – 3 hExperienced
≈ 1 h 30 minSuggested range45 min – 2 h 15 minBased on one person building the set for the first time, following the original instructions and using numbered bags where supplied. Includes normal piece-finding and minor adjustments; excludes long breaks, filming, dismantling and modifications. Sources may use different methods. This range is neither a statistical interval nor a limit: your build may take less or more time.
How we estimate times · sources and method
A compact hull, propeller axles and arm joints. The three central durations are model-specific editorial assessments. Planning ranges extend approximately from 65% to 145%, rounded to quarter-hours; they are not measured experience-level averages or guaranteed limits.
Sources do not always specify the builder’s experience. The three experience bands are our editorial assessment, based on the complexity of the set and individual accounts where available.
- LEGO Italy · Deep-Sea Research Submarine ↗
This source documents the model’s features and components, not a timed build. No sufficiently verifiable individual building-time report has been identified for this set.
- LEGO building instructions · Deep-Sea Research Submarine ↗
Set-specific instructions checked against the set number, piece count and year. The duration is an editorial assessment based on piece count, construction type, mechanisms and detail.
Checked: 23 ottobre 2026 · Method v1.0 · Limited reports; not a statistical average.
BUILT BY THE COMMUNITY
Yours could be the first building time.
0 reviewed solo building times.
No solo building times have been reviewed yet. You can still find editorial estimates under Suggested times.
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Build your own story.
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How much display space does it need?
Model or component measured by LEGO
- Height
- ≈ 15 cm
- Width
- ≈ 15 cm
- Depth / length
- ≈ 25 cm
These measurements refer to the model or component in the original specification below. Other builds, poses or arrangements may need additional space.
Check your shelf space
Which model was measured? · original Italian specification
Dimensioni: set di 413 pezzi con un modello che misura 15 cm di altezza, 25 cm di lunghezza e 15 cm di larghezzaApproximate assembled-model measurements, not packaging dimensions. Allow extra room for handling, moving parts and the display stand. The comparison uses the measured model’s overall footprint, allows a 90° rotation and does not assess stability or shelf load. Source LEGO ↗ · 2026-10-29
BEYOND THE BRICKS
Did you know?
Inside the set
Three propellers
Working propellers accompany steering and three buildable air tanks.
LEGO sourceRecovery on the seabed
An extending arm grips the included barrel.
LEGO sourceBeyond the set
The stories, places and inventions behind your build.
Robots tethered to a ship
Real ROVs are underwater robots controlled from the surface through a cable carrying commands and data.
Read the full story
The tether carries commands down and data, including live video, back to the ship. Some systems use a higher companion vehicle to absorb ship movement. The connection is part of the control, power and observation system rather than merely a visible restriction.
Hands on the seabed
Manipulator arms collect geological and biological samples without sending a person inside the vehicle.
Read the full story
ROV manipulators can collect biological and geological samples into onboard containers while pilots guide work using camera views. Exploration can therefore connect observations with physical material, allowing scientists to study encounters without being on the seafloor themselves.
Expanded stories updated on 29 October 2026
Written by HowLongToBuild · Sources are linked with each story · Checked on 23 October 2026. Historical facts and story details refer to the context described.
THE COMMUNITY’S EXPERIENCE
What was it like to build?
Three separate scores from 1 to 10. For difficulty, 1 means very easy and 10 means very difficult.
No approved ratings yet. Scores are never generated by this site or inferred from the recommended age.
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Building tips from the community
Specific steps, useful checks and sticking points. Contributions appear after moderation, in their original language. Do not upload instruction pages or personal contact details.
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Sign in to contributeSET THE MOOD
A soundtrack for your build
· Selected for the subject and atmosphere
La mer’s orchestral surges and suspended moments complement water and movement. This is a musical reading of a landscape, with quieter alternatives available.
OUR PICK
Debussy: La Mer & Nocturnes
André Previn · London Symphony Orchestra
Narrative and cinematicEditorial suggestions, not official soundtracks for the set. External services may require an account or subscription; editions and availability can vary by country. Suggest another soundtrack →
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YOUR NEXT BUILD
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Official LEGO® image · © LEGO Group and/or the respective rights holders. Source: LEGO Italy ↗
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Official LEGO® image · © LEGO Group and/or the respective rights holders. Source: LEGO Italy ↗
Official LEGO® image · © LEGO Group and/or the respective rights holders. Source: LEGO Italy ↗
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