Updates to Plans
We spent the 2006 season sailing our Merlin Tucanu. This was the first time I had cruised an open deck catamaran for 15 years (but I did cruise and race a Wizard in the mid 1990's) As a result I have a few ideas that will improve both comfort and performance. The sketches are given to give you an idea. I am not offering these changes as detailed plans, but those of you who have already built your own boat should be able to make something similar without any problems. They are drawn for Merlin, but should also work, with modifications, on Janus and Strider.
1) I like telescopic tiller extensions, one on each side. However they are very expensive. So I got telescopic boathooks, removed the ends and fitted a universal joint. Total cost was 1/4 the real thing. After a seasons heavy use they are still working well.
2) To reduce forestay sag and mast loads the new Tucanu rig has a bowsprit and a forestay that is 500mm aft of the original position. Thus the genoa is smaller (and so easier to handle) while we are fitting a new larger racing mainsail, see below
3) Many people now use a "squaretop mainsail" for racing. This is very similar in concept to the mainsail I made for Cockleshell Hero back in 1980! We ordered a triradial carbon sail from GM Sails in Australia. CLICK HERE to see the new rig. But please note that the Strait of Georgia, where we race, is an area with predominately light winds and flat seas. Unless you are very experienced this rig may be too powerful for English Channel sailing, for example.
4) The Shadow/Strider Club had a deep mastbeam which we found a big improvement over the standard beam. The new Tucanu beam is shown HERE. It also has the advantage that the mast foot and hence boom is higher (note you will need longer rigging). If you do not use this deep beam and have a wide beam version of a micromultihull then I recommend fitting a dolphin striker under the mast beam to limit deflection.
5) The micromultihull daggerboards were originally drawn to make the best use of plywood sheets. However for optimum performance you can extend the length of the boards between 250 and 300mm.
6) Maybe we are too old for small boat cruising, but we like more undercover space. So we are making a small cuddy. This will be removable when racing and will fit in our truck for transport. It can have a fixed nacelle or a "pop bottom" as used on Wizard and Sango. The bottom needs to be 9mm ply, but the rest can be as light as you dare. You may also need to recut the genoa to fit.
The photo shows the almost complete cuddy being fitted to Tucanu's deck
To see the general cuddy details CLICK HERE
To see the cuddy dimensions CLICK HERE
To see the pop bottom details CLICK HERE
These drawings make the cuddy look large, so CLICK HERE to see the cuddy with rig above - much better visually! You will notice that the boom is angled up to give yet more room as we found ducking under the boom hard on our backs and knees. This change was easy to make, as we simply cut the sail along the first seam.
Just to repeat, these sketches are to give you ideas. At this stage I am not going to draw detailed plans.
Download Plans
Although we spent a great deal of time and effort in making our plans available in electronic format unfortunately a few errors crept in.
So please use this page to update and correct the download drawings. Some of the errors we have noticed ourselves, but please let us know of any more so that we can update this page and make the download drawings as accurate as possible.
Thank you
Study Plans
As you will see elsewhere, the study plans come with a link to webpages that include the Materials List, photographs, owners reports etc. If you find that clicking on the link doesn't get you the pages you want then I suggest you copy and paste the link into your browser.
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General Notes:
The normal method of marking out plywood bulkheads using full size patterns is to lay the pattern on the plywood. Then "prick though" the pattern with a nail or bradawl at say 1in or 30mm spacing. Remove pattern and "join the dots"
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Pixie
Materials list
The metric measurements are the final timber sizes. But many builders
use thicker pieces of wood as they are easier to obtain, and they don't
then bother to plane them thinner. There is no problem doing that if you
want to save time.
Deck jig
1 sheet 8ft x 4ft.(2440 x 1220mm) 12mm thick chipboard
Approx 6m 2" x2" (45 x 45mm) and 10m of 3" x 1" (70 x 20mm)
rough sawn timber.
Misc
Copper wire 10m minimum (we use old household wiring)
Bulkheads
Bhd2
217 width at deck, 95 width at 150 above keel, 47 deck camber
Bhd 3
40 Deck camber
Transom
88 width at deck, deck camber 8, 150mm above keel width is 55, gunwale
is 150+127=277 above keel
Deck Jig
Reading from the left of the drawing the measurements are: 5, 140(horizontal dimension), 30, 100, 150, 183, 195, ALL 500 (horizontal dimension), 195, 180, 145, 90, 140 (horizontal dimension), 70 The cutout in the jig doesn't have to be too accurate as the ply will form a fair shape.
Rudders
The rudder drawing reads: Steering is more positive if "Ackerman Linkage" is used (as on the front wheels of cars). This can be done by making cranking tillers (angle in 10deg) as shown dotted below
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Quattro 16
Notes for Quattro Full Size Patterns
It is important that the patterns are printed out at the correct size!! Print out on A1 paper
Sheet 1 Bulkhead Patterns
Total Vertical Distance BHD4 must be 565mm
OR if you cannot easily print out the full size patterns you can use the following offsets. Draw a fair line through all points. NOTE: You will soon discover that the "stitch and glue" method used is not particularly accurate as the plywood forms its own fair curves. Thus the bulkheads may not fit exactly.
Use the full size pattern drawing for other bulkhead details
BHD 1
Height gunwale to keel 492
Max Deck Camber 18
Gunwale half width 100
Then half widths at 100mm spacing working down from gunwale to keel
92, 83, 67, 41
Keel width 0
BHD 11/2 (note this is a half height bulkhead)
Height gunwale to keel 282
Max Deck Camber 0
Gunwale half width 122
Then half widths at 100mm spacing working down from gunwale to keel
93, 49
Keel width 0
BHD 2
Height gunwale to keel 532
Max Deck Camber 43
Gunwale half width 206
Then half widths at 100mm spacing working down from gunwale to keel
188, 162, 135, 93, 41
Keel width 20
BHD 3
Height gunwale to keel 516
Max Deck Camber 72
Gunwale half width 246
Then half widths at 100mm spacing working down from gunwale to keel
220, 188, 151, 106, 37
Keel width 23
BHD 4
Height gunwale to keel 498
Max Deck Camber 67
Gunwale half width 233
Then half widths at 100mm spacing working down from gunwale to keel
205, 174, 138, 91
Keel width 22
BHD 5
Height gunwale to keel 400
Max Deck Camber 38
Gunwale half width 170
Then half widths at 100mm spacing working down from gunwale to keel
142, 112, 72, 26
Keel width 22
Transom
Height gunwale to keel 295
Max Deck Camber 15
Gunwale half width 100
Then half widths at 100mm spacing working down from gunwale to keel
77, 46
Keel width 12
Sheet 2
Hull Centrelines on Cross Section Setup for Fitting Keels Horizontal Distance must be 195 mm when printed out
CLICK HERE for a dimensioned sketch of the Quattro 16 keels
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Janus
Unfortunately there was a problem when these with these drawings were scanned. They are being re done. As a temporary fix I will send paper sheets, as required, to those who need them (Note: Not to partial plan customers, but only to those with full plans)
Sheet 2
Keel panel dimensions
Reading from aft the half widths are 137, 145, 170, 195, 205, 210,
205, 190, 165, 125, 70, 16. The spacing is 600 except 140 for the two
aft widths.
Setup Note 6) Fix string to Bhd 4 on WL/CL intersect (bunk top). Pull
tight and horizontal (check with spirit level) through Bhd 5 to Bhd 6.
Temporarily clamp legs to Bhd 6 and offer up and adjust height so that
string and WL are horizontal. Screw legs to Bhd 6 and brace as before
(see 2B IV)
Setup Note 9) Fit side stringers, beginning at the keel and working down. Fit port and starboard stringers at the same time. Check that hull is not twisting as stringers are fitted. Glue and screw as 8) above. Note: if stringers are not long enough they should be scarphed together before fitting, see sketch at 2B1. Stem see VIII, IX, X
Sheet 3
General Procedure Deck Framing
Note: Interior should be finished and painted before fitting any deck
framing
After fitting cabin shelves (see 3AXI) begin fitting deck framing at bow
and work aft.
Check that stem, Bhd 1, 2 and deck beams 1, 2 form a fair camber curve
before decking, plane as necessary.
Hatch side coamings are fitted after decking - see Sheet 5
Before fitting sloping cabin front the foredeck should be fitted to deckbeam
3 and forward beambox
Find deck beam 3 position by holding straight edge (or timber 'A' in sketch
3BIII) from Bhd 4 to Bhd 3 and then to gunwale
Bed central roof stringer on epoxy filler on foredeck - position depends
on own boat - see Sheet 5
Deck stringers need slight bevel before decking. See Sheet 5
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Sango
Offset table
Although the full size patterns are correct I still include an offset table for use as a check. I recently discovered a couple of errors in the table:
Frame 3 WL2 should be 215
Frame 4 WL3 should be 188
Frame 5 WL3 should be 202
Frame 8 WL2 should be 217
Daggerboard Position
The drawings show the daggerboard cases fitted on the outside of the hull. That is so that they do not interfere with the wing lockers. However the photo sheets show the daggerboard case on the inside of the hull. The builder whose boat I photographed chose this position to make it easier to reach and adjust the boards.
There is no real difference in performance between the two positions so the choice is yours.
Sango and Wizard Basic Hard Chine Materials List
Hull planking 12 sheets 6mm ply 3 sheets 9mm ply
Decking 6 sheets 6mm ply
Timber 2in x 1in 200m 1in x 1in 100m
NOTE: all plywood to be best quality gaboon (okume) marine grade
All timber to be best quality softwood eg Douglas fir, sitka spruce, yellow
cedar or similar.
NOTE: Timber sizes are nominal. Planed all round (PAR)
Glass sheathing 300g glass cloth (hulls) 36sq m 200g glass cloth (decks)
12sq m Epoxy 30kg min Fastenings Either 1in counter sunk stainless steel
self tappers or gripfast/anchorfast barbed ring boat nails Approx 2000
reqd
Wizard needs 3 fewer sheets 6mm ply
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Skua
Tillers should be 700, not 480 long
Rudders can be 150mm shorter.
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Gypsy
Daggerboard
The total length of the board is 3050mm and the part below the waterline is 1350mm
