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Blackfly Dinghy - Free Plans

These plans were NOT made by me! I noticed a while ago that the plans for this great free boat design had disappeared off the internet so I contacted the original author/designer and asked for his permission to publish them here. He agreed, so enjoy the return of Blackfly!

Blackfly, a camping dinghy for sail and oar.



LOA: 14'

Beam: 4'

Weight: 80 lbs, stripped

Depth, midships: 1' 1 1/2“

Depth, stem: 1' 10”

Rig: Standing lug, 75 sq. ft.

Construction: lapstrake plywood

Designer: Bruce Taylor


About The Design

Epoxy Basics Working with epoxy cleanly and efficiently, e-book by Russell Brown

Blackfly was designed for my own use on the lakes and rivers of Western Quebec. I wanted an open sailboat that would be light enough to portage and cartop, but capable of carrying as much cargo as an ordinary tandem canoe. The result is a burdensome but lightly built craft, suitable for sheltered waters in fair weather.

The boat is nimble and mannerly under sail. However, Blackfly, as drawn, has no enclosed bulkheads, decks or built-in flotation. If built to the very light scantlings given in the plans, she should be sailed somewhat conservatively. For a more aggressive style of sailing, it would be possible to add flotation and increase scantlings, but that would add weight and reduce stowage. There are always tradeoffs.

Blackfly is primarily a sailboat. The prototype has not been tried with a motor.

Blueprints and full-size templates are not available. I try to answer questions promptly, but builders who feel the need for more detailed plans should probably consider building one of the many fine boats from such designers as John Welsford, Iain Oughtred and Arch Davis.

Feel free to use and distribute these plans, but please understand that anyone who chooses to build a boat from the information provided on this site does so at his or her own risk. The designer takes no responsibility for injury or accident that may result from the use of this design

I'd like to thank Rolf Verheij for supplying metric lines and tables of offsets, and Stephen Berg for spotting an error in the diagonals. Thanks as well to the knowledgeable participants of the WoodenBoat Forum, who helped me to develop and refine this boat.


Click on thumbnail to see the full image.


Some Construction Photos

Note: The Blackfly prototype differs slightly from the plans. Click on thumbnail to see the full image.


Lines - Pics

Click on thumbnail to see the full image.

Body Plan
Profile, Buttocks
Construction Plan
Construction Profile
Midship Section


The plans for Blackfly are available in several formats.

Click here (1.1mb) to download linesplan, offsets in imperial measurements and materials list in .PDF form . You will need Adobe Reader.

Click here (3.5mb) for a Word document showing lines and offsets with metric measurements. Thanks to Rolf Verheij for converting the data from imperial to metric. Click here (750kb)for the same document in .PDF form.

The following 2 downloads are zipped files (.ZIP). You will need to unpack them to view the files with a program like WinRAR.

Click here (434kb) to download .DXF files. You will need a CAD program to view these.

Click here (665kb) to download .DWG files. This is AutoCAD's native format.

Another great Blackfly dinghy has been built!

A blog with fantastic pictures of a blackfly model. Step by step construction photos!

Here is a building log for a boat of similar constructions. The text is in japanese (I think) but the fantastic pictures aren't!

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