1989 Catalina 36 Specs: Construction

Main SpecsGeneral

Our 1989 Catalina 36 MkI, Meander, is an aft cockpit, masthead rig sloop with raked stem, reverse transom stern, and bolted ballast.

The Catalina 36 MkII, circa 1991, is CE-rated A for offshore passagemaking, and by all accounts, the hull and structural design remained essentially unchanged compared to Meander.

This is a cropped photo of the original spec sheet for Meander:

—36’4″ length overall (LOA)
—30’3″ length on waterline (LWL)
—11’11” beam, and
—13,500 pound displacement.

The fin keel allows the lighter sailboat to tack more easily, maneuver in tight harbors (in forward and reverse) with much greater ease than a full keel, and come about quickly to rescue your husband who peed off the stern and fell in (I’ve tested the first two, and dread the latter 😉 ).  To obtain the same righting moment as a full keel, fin keels are generally deeper: Meander’s keel drafts 5′ 10″.

In regards to Meander’s structural sufficiency, the last valid survey for Meander reports:

The vessel was found generally well-kept and clean, and with exterior and interior protective coatings generally intact.  The vessel is constructed of apparent good and adequate scantlings and to accepted standards and practices.

We have found this to be true, so far!


D/L is 241, placing her at the lower end of moderate displacement hulls, and the heavier end of light displacement hulls.  In practice, she is excellent in light air, but pounds to weather, and benefits from early reefing and minimizing heel.


All Catalina 36 from this time period have solid glass reinforced plastic (GRP) hulls, and plywood-cored cabin tops.  A GRP liner is tabbed in after the hull layup, then the cored decks are screwed (and an occasional bolting) to the hull using a shoebox flange, reportedly bedded in butyl or glass putty.  Dirty!  Hull thickness is reported as  1″ at the centerline and 5/8″ on bottom panels.

Note:  GRP specifically refers to fiberglass laid up in a matrix of resin.  FRP is a more general classification including Kevlar and other exotic fibers.  I generally assume GRP for construction purposes unless told otherwise.  Also, generally, the resin most commonly used in fiberglass boat layup in the ’80s is polyester. The MkII (1993-??) added vinylester to the hull layup, and less woven.  Newer boats tend to have more exotic materials involved.  Man, makes me want a Bestaever….if I could afford her!

As I interpret, (and please, contact and correct me if I’m wrong!) the hull derives varying portions of integrity from the GRP layup of the hull, the interior GRP liner, the plywood bulkheads, and the GRP stringers.

Deck/Hull Flange

Shoebox Joint
What is the best method for securing the hull –Don Casey, Sail Magazine, Feb 2015

Meander is missing her rub rail.  The rub rail conceals and protects the deck/hull flange, so she’s had her sensitive bits exposed to weather for a while.  Alas, we still haven’t reinstalled it.  The PO had bought one aftermarket, and it didn’t fit.

PAR, a pretty reputable commenter on Cruisers’ Forum, had this to say about the shoebox flange, in reference to an original poster asking about repairing a gaping deck to hull joint in the vberth area of a 22 footer.  Honestly, the most information I’ve found on this mysterious part of the boat outside of Don Casey (with a little help from GordMay, moderator emeritus).


I wouldn’t call the two structural bulkheads securely fastened either: 1/2 inch marine grade plywood, screwed to the interior liner and cabin top.  Several anecdotal reports of Catalina bulkheads breaking loose, especially one of a relatively well-founded Catalina heading offshore to Hawaii which started falling apart after a day or two of pounding upwind, make me a tad nervous.


About the stringers: uniformly, drainage between stringers (and towards a bilge pump) is achieved by drilling holes after layup, and MAYBE attempting to seal it with some resin.  Again, uniformly, however, the result, either way, is an unsealed penetration into the wood forming the core of the stringer, because subsequent application of polyester resin adheres poorly to cured polyester resin.  This is why everyone uses epoxy resin for filling deck penetrations, among other boat repairs.  The result:  rotten stringer wood in spots.   I’ve mentioned Meander has a damp bilge, thanks to not having a mast dam below the lower halyard sheaves (which we’ll correct as soon as the weather warms up–no point in installing a mast dam when the aluminum is shrunk to a nubbin at below freezing temps.)

I’m not sure if the wood is structural, or just a convenient form for the fiberglass.  Some say aye, others nay.  If anyone related to Catalina knows the structural parameters of the design, or if a third party happens to have access to resources documenting the structural elements—contact me!

At the moment, I am fairly sure the three stringers spanning the center, from under the forward fiberglass portion of the galley, to just aft of the mast base, are at least soaked, as are the motor mount stringers.


The last known survey (circa 2012) describes the keel:

Ballast foil bolted to stub keel of hull.  Keel bolts as visible from within appear in good order…Sound as examined; with no evidence of hard grounding, osmotic blistering, other damage, or previous major repair…The lead keel does show evidence of soft grounding at the leading edge, considered nonstructural, and the keel to hull joint shows fairing from a previous keel removal.  The previous owner reports the keel was removed and the bolts inspected/replaced early 1990s.

We stuck Meander in the sling for a water to water haulout, Spring 2017.  Based on our inspection (and LOTS of video, which has way too much inane commentary on our part to ever be posted for public ridicule), she needs a proper haulout, scrubbing, fairing of her leading edge, and new antifoul–but no evidence of waggle, keel separation, or signs of more serious trauma.

We swapped zincs, surreptitiously scraped a few small lifeforms from the shaft, propeller, and knotmeter, and stuck her back in the water.  Only in arctic waters.  I did later scrub the hull as far as I could reach from the dinghy, using a long-handled deck brush.  (In case you didn’t know, Seward had a Real. Wet. Summer. this year.  Even for Seward.  Honestly, I had more growth to contend with above the waterline!)


Catalina 36 Offshore?

MkI vs MkII at the Catalina.org owners association.

I love Practical Sailor:  Catalina 36 MkII Review (2 years after Meander’s birthday, close enough.)

Raised Cabin vs flush deck at Boatdesign.net (because our old survey also calls Meander a “flush deck”  Hmm.

Crunching Numbers at Boats.com to figure out how much gear we could add before she becomes a heavy displacement boat.

D/L and Stability at Sailboat Cruising

Modern Sailboat Design on Sailfeed

The Catalina36.org forum on the kind of intermittent winds frequently encountered in Alaska (although not specifically regarding Alaska).

Sailboat Cruising on Stability, Buoyancy and Performance

Kasten Marine on Rigging (a whole other section but I got squirreled.  Squirrelly.)

Talk of shoebox flanges a bit on this thread.




Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s