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Region

Sets
Dacta
Technic
Mechanical Engineering

9665 LEGO Dacta Technic Mechanical Engineering

Name: LEGO Dacta Technic Mechanical Engineering
Brand: LEGO
SKU: 9665-1
Rating: 4.5 (17 reviews)

Images 1

9665 LEGO Dacta Technic Mechanical Engineering

Set Value (New/Sealed)

This chart represents the current new/sealed value of the set Mechanical Engineering since January 2020. Medium accuracy

LEGO 9665 Mechanical Engineering was a 318 piece Dacta set released in 2003. The current value for a new and sealed Mechanical Engineering is estimated at $350, with an average annual growth of approximately 4%. Current used prices for Mechanical Engineering range from $285 to $323, depending on the set's condition, with an average price of $291 for those in good overall condition.

All regions

All regions 2
United States 1

For Sale (New/Sealed)

	(US) eBay listing for Mechanical Engineering	$339.50 -3.0%
	(MX) BrickLink store Bricks Store Mexico	$350.00

Sets in Dacta / Technic


	9609 Technology Resource Set Theme / Subtheme Dacta / Technic Year 1995 Pieces 1,718 Availability Retired Buy this set at eBay	Value $1,115.17 I own this set I want this set

	1034 Teachers Resource Set Theme / Subtheme Dacta / Technic Year 1985 Pieces 1,501 Availability Retired Buy this set at eBay	Retail $129.00 Value $883.10 Growth +584.6% Annual growth 6.2% I own this set I want this set

	9701 Control Lab Building Set Theme / Subtheme Dacta / Technic Year 1995 Pieces 557 Availability Retired Buy this set at Bricklink	Retail $149.00 Value $391.24 Growth +162.6% Annual growth 3.3% I own this set I want this set

	9700 Technic Control Centre Theme / Subtheme Dacta / Technic Year 1987 Pieces / Minifigs 471 / 4 Availability Retired Buy this set at eBay Bricklink	Value $379.43 I own this set I want this set

	1092 Technic Control II Theme / Subtheme Dacta / Technic Year 1986 Pieces 463 Availability Retired Buy this set at Bricklink	Retail $191.00 Value $261.67 Growth +37.0% I own this set I want this set

	9618 Structures Set Theme / Subtheme Dacta / Technic Year 1997 Pieces 463 Availability Retired Buy this set at Bricklink	Retail $79.90 Value $123.51 Growth +54.6% Annual growth 1.6% I own this set I want this set

	1090 Technic Control 1 Theme / Subtheme Dacta / Technic Year 1986 Pieces 404 Availability Retired Buy this set at Bricklink	Retail $139.99 Value $197.97 Growth +41.4% I own this set I want this set

	1032 Technic II Powered Machines Set Theme / Subtheme Dacta / Technic Year 1984 Pieces 278 Availability Retired Buy this set at eBay	Retail $79.99 Value $178.05 Growth +122.6% Annual growth 1.8% I own this set I want this set

	9630 Simple Mechanisms Set Theme / Subtheme Dacta / Technic Year 1997 Pieces 277 Availability Retired Buy this set at eBay Bricklink	Retail $79.99 Value $227.50 Growth +184.4% Annual growth 3.8% I own this set I want this set

	9605 4.5V Technic Resource Set Theme / Subtheme Dacta / Technic Year 1995 Pieces 268 Availability Retired Buy this set at Bricklink	Retail $74.99 Value $453.59 Growth +504.9% Annual growth 6.2% I own this set I want this set

	9702 Control System Building Set Theme / Subtheme Dacta / Technic Year 1993 Pieces / Minifigs 221 / 2 Availability Retired Buy this set at eBay Bricklink	Value $233.17 I own this set I want this set

	1030 Technic I Simple Machines Set Theme / Subtheme Dacta / Technic Year 1985 Pieces 179 Availability Retired Buy this set at eBay	Retail $74.99 Value $123.81 Growth +65.1% Annual growth 1.3% I own this set I want this set

	9604 Technic and Pneumatic Elements Theme / Subtheme Dacta / Technic Year 1992 Pieces 124 Availability Retired Buy this set at Bricklink	Retail $36.95 Value $64.52 Growth +74.6% Annual growth 2.4% I own this set I want this set

	1038 Universal Buggy Theme / Subtheme Dacta / Technic Year 1985 Pieces 119 Availability Retired Buy this set at eBay Bricklink	Value $67.57 I own this set I want this set

	9937 Small Chain Links Theme / Subtheme Dacta / Technic Year 1998 Pieces 108 Availability Retired Buy this set at Amazon ebay	Retail $7.49 Value $13.80 Growth +84.2% Annual growth 2.5% I own this set I want this set

	9617 Introducing Air Power Theme / Subtheme Dacta / Technic Year 1997 Pieces 89 Availability Retired Buy this set at eBay Bricklink	Retail $29.99 Value $163.87 Growth +446.4% Annual growth 6.3% I own this set I want this set

	9614 Pulleys Mini Set Theme / Subtheme Dacta / Technic Year 1993 Pieces 77 Availability Retired Buy this set at eBay	Retail $14.99 Value $32.29 Growth +115.4% Annual growth 2.4% I own this set I want this set

	9616 Wheels and Axles Set Theme / Subtheme Dacta / Technic Year 1997 Pieces / Minifigs 74 / 1 Availability Retired Buy this set at Bricklink	Retail $14.99 Value $29.99 Growth +100.1% Annual growth 3.3% I own this set I want this set

	9610 Gears Set Theme / Subtheme Dacta / Technic Year 1993 Pieces / Minifigs 67 / 2 Availability Retired Buy this set at eBay	Retail $12.50 Value $24.74 Growth +97.9% Annual growth 4.2% I own this set I want this set

	9612 Levers Set Theme / Subtheme Dacta / Technic Year 1993 Pieces 62 Availability Retired Buy this set at Amazon eBay	Retail $14.99 Value $30.89 Growth +106.1% Annual growth 2.8% I own this set I want this set

	9938 Conveyor Belt Links Theme / Subtheme Dacta / Technic Year 1995 Pieces 38 Availability Retired Buy this set at Bricklink	Retail $6.25 Value $12.78 Growth +104.5% Annual growth 8.3% I own this set I want this set

	9848 9V Lamps Theme / Subtheme Dacta / Technic Year 1997 Pieces 9 Availability Retired Buy this set at Bricklink	Retail $2.99 Value $32.08 Growth +972.9% Annual growth 7.2% I own this set I want this set

	9615 Motor Add-On for Simple Mechanisms Theme / Subtheme Dacta / Technic Year 1997 Pieces 3 Availability Retired Buy this set at eBay Bricklink	Retail $31.99 Value $44.68 Growth +39.7% Annual growth 1.6% I own this set I want this set

	9751 Control Lab Serial Interface & Adapter Theme / Subtheme Dacta / Technic Year 1995 Pieces 2 Availability Retired Buy this set at eBay	Value $182.19 I own this set I want this set

	9876 Large Turntables Theme / Subtheme Dacta / Technic Year 1992 Pieces 2 Availability Retired Buy this set at Bricklink	Retail $8.75 Value $18.16 Growth +107.5% Annual growth 3.6% I own this set I want this set

My Collection

I own this set

I want this set

Set Details

Set number

9665-1

Name

Mechanical Engineering

Theme

Dacta

Subtheme

Technic

Year

2003

Availability

Retired

Pieces

318 (PPP $0.47)

Set Pricing

Retail price

$149.99

New/Sealed

Value

$350.00

Growth

+133.35%

Annual growth

+4.12% Decreasing

Used

Value

$290.50

Range

$284.98 - $323.33

Quick Buy

eBay

Buy

Price

$339.50

Bricklink

Buy

Lowest price

$350.00 (MX)

*Listings are for new/sealed sets.

Set Predictions

New/Sealed

Today's value

$350.00

1 year forecast

$364.42+4.12%

5 year forecast

$421.43+20.41%

$418

$433

9665 Mechanical Engineering is projected to be valued between $418 - $433 within five years.

Mechanical Engineering Reviews

17 ratings

4.5

Collectors

Investors

Subtheme Analysis

Dacta / Technic

Sets

Years

1984 - 2003

Annual growth

+2.54% (this set +4.12%)

This set's annual growth (CAGR) vs. subtheme

Community Stats

Mechanical Engineering currently ranks #14 out of the top most owned sets in Dacta Technic.

#1Technic I Simple Machines Set

#2Simple Mechanisms Set

#3Technic II Powered Machines Set

#4Levers Set

#5Gears Set

#14Mechanical Engineering

#15Control Lab Building Set

#16Technology Resource Set

About Dacta Technic

The LEGO Dacta Technic theme is a segment of the LEGO Dacta (later rebranded as LEGO Education) line, focusing on the Technic system of LEGO building. These sets are designed for educational contexts, emphasizing principles of mechanics, engineering, and applied science. Through specialized pieces like gears, axles, and beams, the Dacta Technic theme offers a hands-on approach to understanding complex mechanical concepts, making it a resource for classrooms and other educational settings aiming to teach STEM principles.

Technic consists of 30 sets that ran from 1984 to 2003. As of today, 9609 Technology Resource Set is the most valuable Technic set with an estimated new/factory sealed value of $1,115.

Set Pricing Models

BrickEconomy uses a number of methods to determine the value of a set.

New/Sealed

Machine Learning/AI Model

Value (today)

$350.00

Value (in a year)

$364.42

Value (in 2 years)

$378.84

Accuracy

0.920200 High

Statistical Model

Value (today)

$342.96

Value (in a year)

(Possible plateau)

Value (in two years)

(Possible plateau)

Accuracy

0.800581 High

Used

Machine Learning/AI Model

Value (today)

$290.50

Value (low range)

$284.98

Value (high range)

$323.33

Accuracy

0.865200 High

To learn more about how we calculate pricing and forecasting, check out our article on BrickEconomy’s Approach to LEGO Pricing and Future Value Predictions.

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