Model Boat Mayhem

The Shipyard ( Dry Dock ): Builds & Questions => Yachts and Sail => Topic started by: Edward Pinniger on October 30, 2011, 03:43:42 pm

Title: Repairing a cracked ABS yacht hull - advice needed
Post by: Edward Pinniger on October 30, 2011, 03:43:42 pm
I have a model sailing yacht with an ABS hull which has recently developed a hairline crack on the upper hull side, at the location of one of the internal wooden bulkheads. The crack is well above the waterline, but I want to repair it as soon as possible to stop it developing further (the hull is 30+ years old and was broken at the keel when I got it, so the crack may well have been present before I acquired the boat, and opened up by the stresses caused by sailing).
What is the best method to repair a cracked ABS hull? I was thinking of painting expoxy resin (the sort used for GRP) over the inside of the cracked area, then possibly putting some duct tape over the top for extra reinforcement. However, I'm not sure if GRP epoxy will bond to the ABS well enough, or if it will be too inflexible once cured.
I'm reluctant to attempt using a solvent like Plastic Weld to glue the crack together, as I've found solvents can actually worsen fractures in plastic if the parts are still under stress. The presence of the wooden bulkhead on the inside also makes it hard to glue a "patch" over the area.
Title: Re: Repairing a cracked ABS yacht hull - advice needed
Post by: Shipmate60 on October 30, 2011, 05:36:08 pm
The last time I repaired an ABS hull I used a plasticard "patch" on the inside of the hull.
When dry I carefully ground out the crack to ensure anything in the crack was removed.
bonded the hull to the backing plasticard by running some plastic weld in the enlarged crack, then used car plastic bumper filler to fill.
Smooth off and paint.

Bob
Title: Re: Repairing a cracked ABS yacht hull - advice needed
Post by: Circlip on October 30, 2011, 06:25:39 pm
Standard way to repair the Graupner Cirrus ABS fuzegulge after an "Arrival" was to glue with Uhu Hart (Balsa cement) and a cotton bandage wrapped around the break. Note, Balsa cement is a solvent adhesive for ABS. Plumbers ABS pipe solvent cement is cheaper.

   Regards  Ian.