ADHESIVE SEALANTS 

 

This is a general overview provided by an Irwin owner and others.

Read directions on each product carefully!  Ed.

POLYSULFIDE

Synthetic rubber: good sealant/bedding, caulk, and adhesive, beds everything, except plastic (lexan, Plexiglas, acrylic polycarbonate, ABS, PVC).  Does not shrink, good for deck fittings, one part, cures slow, rubbery, pliant, removable, sandable, paintable, good underwater.  

Brands:  3M 101, StarBrite-QuickCure, BoatLife-LifeCalk

POLYURETHANE

Permanent adhesive-sealant, bonds well except to plastic (same as above), good underwater (hull/keel, thru hull), less pliable, cures slow.

Brands:  3M 5200 (remove with Anti-Bond 2015(r)) (3M 4200 is less permanent and more flexible), Sikaflex 240/241/291/292/296 (can use 295UV on plastic), Plexus (2 part)

SILICONE
 
Good for gaskets under compression, stays pliant, not an adhesive or caulk, not for underwater, good with plastics, lexan, and metal, good insulation, do not paint. Its carrier/blocking agent can be acid (vinegar smell) or ammonia. Use marine grade (ammonia)

Brands: 3M-Marine Grade Mildew Resistant Silicone, GE 8100 (high strength, fast), GE 8200 (bedding trim & hardware), GE 8300 (fast, translucent, low modulus, hatch & window)

SILICONE/POLYURETHANE HYBRID

Good for port lights, above/below waterline, good sealing and adhesion. Not for wood.
 
Brands:  BoatLife: Life Seal, Life-Calk Deck Seam Filler (2 part)

GENERAL

Use Acetone or MEK to clean parts.  Do not touch cleaned parts with bare hands, use rubber gloves(oils from fingers will compromise bonding surface).  For the polys, mask the parts before bedding. For the silicone, use a knife to remove excess. A plastics supplier will sell the correct adhesive. Countersink holes to make a sealant "dam."  See http://www.thistothat.com/

Plastic - If cellophane tape won't stick to hard plastic, most glues won't. For hard plastic - plastic cement, superglue, urethane, epoxy or acrylic.

Wood indoors - emulsion; wood outside - resin.

Metal or ceramics - small jobs/superglue, large jobs/epoxy.

Glass - epoxy if it will be washed, if not - superglue (gel if ragged, liquid if smooth).

Plexiglas - Methylene chloride solvent. 

Polycarbonate - Lexel solvent.

Bedding Tempered Glass windows and new replacement plexi lenses in hatches

Use Dow Corning #795 Silicone

Silicone Building Sealant

Available through industrial suppliers

Such as: Coastal Construction Products

904-398-7171

www.coastal-fla.com

This is what the mega yachts use to hold in those large flush glass windows without frames,  i.e.:  West Ship, Lazarra yachts, Catalina, etc.  Not cheap but works 

Available in multiple colors

For removal of adhesives:

http://www.marineformula.com/