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Hybrid Cirrus - Stitch & Glue hull with wood strip deck
(plywood, hard chine hull)

Technical specs...


 Classic, hard chine 'Greenland style' touring kayak for medium to large paddlers - featuring a wood strip deck.







        Hybrid deckPlywood deck


Cirrus description | MATERIALS | S&G KITS

Cirrus All plywood version of this kayak model
Cirrus LT HybridSmaller displacement version of this kayak model
Cirrus SLT Smallest plywood version of this kayak model


Building a kayak with plywood alone is great but imparting your own creative vision into the deck and making your kayak truly unique is even better! The Cirrus hybrid will give you the speed and simplicity of the hull assembly with the visual impact of a wood strip gem. The deck has exactly the same design features as the S&G Cirrus including the overall deck profile - except the deck forms are made specifically for building contoured wood strip deck. The deck assembly for this Hybrid kayak is so easy and fast, you will feel guilty! The spine provides the horizontal reference plane on which the stations rest and the hull markers define the distribution and exact location of the stations along the kayak. That's it. There is NO visual alignment or tedious attachments - hot glue and staples is all it takes to make a precise foundation for your strip deck.

The Plans include complete set of full size stations and the manual instructions are true to the spirit of the kayak - hybrid. You get the full S&G manual plus additional "Wood strip addition to the S&G Manual" in one package!

Cirrus Hybrid plans DO NOT contain plywood deck plates - the deck is STRIP only. The Cirrus is ALL plywood.
The photos below show example of the Hybrid stations setup from the Builders' Pages.



The "spine" below is just a 3" wide strip of particleboard.
  • Assemble the hull
  • Inserts spine with BOW and STERN stations
  • Add on all DECK stations, staple, hot glue. Ready for strips.

Building Material

Technical specs are identical to S&G Cirrus with the exception of the wood strip deck.
PropertyEnglishUnitsMetricUnitsComments
Length Overall 17.5 ft 5,33mlength from bow to stern as designed
Beam Overall 22 in 55,87cmwidest part of kayak
Draft 4 in 10,15cmbaseline to Designed Water Line (DWL)
Volumetric Properties
Displacement 222.8 LB 101,25kgat DWL
Volume 3.48 ft^3 98,54litersdisplacement in cubic feet and liters of sea water
Wetted Surface 19.9 ft^2 1,84m^2underwater surface area to DWL
LCB 8.467 ft 2,58mlongitudinal center of buoyancy from x=0
LCB % LWL53,52%53,52%LCB as a percentage of waterline length from x=0
VCB2.526 in 6,41cmvertical center of buoyancy from baseline
Waterplane Properties
Waterplane area 16.07 ft^2 1,49m^2at DWL
LCF 8.25 ft 2,51mlongitudinal center of flotation from x=0
LCF % LWL52.2%52,2%LCF as a percentage of waterline length from x=0
LWL 15.82 ft 4,821mlength of waterline; same as DWL
BWL 19.45 in 49,42cmbeam of waterline
Sinkage 85.71 LB/in 15,33kg/cmpounds displaced per one inch of sinkage
Form Coefficients (no units, same for metric)
CB 0.407    block
Cm 0.777   midship
Cp 0.524   prismatic
Cwp 0.626    waterplane
Area/Displacement8.66   Area / Displacement ratio [ft^2/(ft^3)^2/3]
Length / Beam9.75   Length / Beam ratio [LWL / BWL]
Miscellaneous
Area of cockpit 2.96 ft^2 0,275m^2for cockpit template in plans (red)
Circumference 6.76 ft 2,06mcockpit
Depth in front 12 5/8 in 32,06cminside cockpit
Depth in rear 10 in 25,4cminside cockpit
Deck area 22.05 ft^2 2,048m^2includes cockpit area
Hull area 32.056 ft^2 2,978m^2 
Kayaker Fit & LoadingMedium to large size paddlers
150 LB min. -> 210 LB ideal -> 250lb max. (68,2 -> 95,5 -> 113,75kg)
Recommended max. load: 270lb (122,8 kg)
Paddler height: 6' 2" and under (188 cm and under)
x=0 the start of waterline (DWL) at bow

All English units (ft / in) in the plans have a Metric (m / cm) equivalent !

.

Material

  Plywood for hull
Unit converter
Metric / Standard unit converter

Hull: The minimum plywood amount for the Cirrus hull is 3 half sheets - 2' x 8' x 4mm marine plywood (60.96cm x 243.84cm x 4mm) or similar. With 4 half sheets (2 full 4' x 8' sheets) the hull can be built very easily. The hull plywood thickness can range from 4mm to 6mm.

Notes & Tips:
  • What is Marine Plywood?
  • If you desire to make the kayak hull from different combinations of plywood, more sheets will be required.
 Wood strips for deck
assumes bead & cove strips and you need either the 5/8" OR 3/4" strips. Not both.
 
Coverage + 'fudge factor' for wasteSurface area (ft2) (m2)Total length of 3/4" strips (ft) (m)Number of 3/4"x 16ft stripsTotal length of 5/8" strips (ft) (m)Number of 5/8"x 16ft strips
Total area of deck (+ cockpit)22.05  (2,04)423  (129)27529  (161)33
Total deck area + 5%23.15  (2,15)445  (136)28556  (169)35
Total deck area + 10%24.25  (2,25)466  (142)29582  (177)36

Notes & Tips:
  • 3/4" strip width = 1,9 cm
  • 5/8" strip width = 1,58 cm
  • 16 feet = 4,87 m
  • The accuracy of figures in the table is within (+ -) few feet
  • For custom calculation, see the Wood strip Calculator
  • The coverage based on the "+ 10%" is most recommended
  • Estimate wood for deck inlays as a percentage of the deck surface area
  • Ideal strip length is between 10 - 16 feet
  Fiberglass coverage
assumes complete coverage of inside and outside of hull and deck to make full sandwich core
 
Coverage of fiberglass
(plain weave e-glass)
yards
(yd)
feet
(ft)
meters
(m)
How to estimate
Deck - 4 oz. e-glass12.7 11,6two times the kayak length + 1 yard (1m)
Hull - 6 oz. e-glass 12.7 11,6two times the kayak length + 1 yard (1m)
2" wide glass tape 7924four times the kayak length + 9 ft (3m)

Notes & Tips:
  • Minimum width of fabric is 38" - will no allow for full hull abrasion patch
  • Order 50" width of the 4oz. Glass to get the extra hull abrasion patch material
  • If 50" fabric is not available, order one 'waterline length - LWL' of additional cloth (any weight)
  • Round figures to the nearest higher number when ordering fabric
  • The 6oz. Glass can always replace the 4oz.
  • See different types of reinforcement fabrics
  • Glass tape is sold in 'feet' and cloth in yards (in the US)
  • Glass tape is used to bond the kayak shells and for additional stem reinforcement
 Epoxy
 Minimum total volume of epoxy mix (resin + hardener): 2.5 to 3 gallons

Notes & Tips:
  • Usage may vary (+-) 0.5 gallon as a result of the thickness of lay-up, fillet size, unused batches, spills, bad (unmixed) batches, care in application (overapplication), additional composite components such as coamings, hatch seals, rudders etc...
  • If epoxy is sold by weight, the density of epoxy is very close to water (1dm3 = 1 liter = 1kg)
  • 1 gallon = 3.8 liters
  • Learn about epoxy

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Last page update: 29 October 2013