Introduction.
On 23rd June, 19 WBAQ members attended a site visit to Ross Lillistone? s establishment at Esk. Of those Ian Kirk and Peter Fox from Macleay Island and Bruce Wollstein from Coochiemudlo Island caught the 0600 ferry to get a ride with Phil Brown from Victoria Point. The group assembled at Fernvale and arrived at Ross? place at about 1000 hrs. During the course of the day, Ross discussed various topics, passed on numerous tips and conducted some demonstrations. The following abbreviated notes, in no particular order, are a summation of the information I collected on the day. I may have missed some.
Mayfly 14 sailing boat . This is a Jim Michalak design. Although it is a simple flat bottom boat and appears to be simple to build Ross found that it was difficult to bend in the bottom near the transom where the rocker is increased. The boat performs very well. It has an external pivoting leeboard similar to Ian Kirk’s boat “Pug”.
Kadoka ply, from PNG. Similar to Gaboon, stronger but softer.
Taped joints. Use double bias glass in 400, 425 or 450 gram, 100 or 150 wide as specified, inside over fillet joint. But may be difficult to get as it is cut from 90m long full width rolls. Double bias has threads running at 45 degrees so all threads cross the joint. In tape only half the threads cross the joint, the remainder run parallel.
Does fillet first then when it is just starting to go off, add tape over and wet out. Wet out past edge then go over edge with a flat tool to smooth down.
Internal painting. Does not epoxy saturate the whole boat internally. One coat of epoxy primer is applied which is generally almost sanded off, then paints with a single-pack paint. The reasoning is that sooner or later the internal epoxy will crack somewhere or be penetrated and if water gets in it cannot get out. Similar to a dry sponge wrapped in Gladwrap. Put a small hole in the Gladwrap and let in a drop of water, the sponge will never dry out. Prefers to use a paint that will breathe. The exception is inside buoyancy tanks.
Inside buoyancy tanks. Uses epoxy saturation and also coats with epoxy primer.
Screws, Uses square drive silicone bronze screws “Yushung” brand available from Brass and Bronze Fasteners
Epoxy. “All marine epoxy is good”. Ross currently uses West System epoxy but only because he wound up with a 1:5 industrial pump. He was using BoatCoat but couldn’t get an industrial 1:2 pump, so got a 1:5 industrial pump from West System with a view to modifying to a 1:2 ratio to use with BoatCoat. But after he purchased it, found that the ratio could not be altered so had to use West System (1:5) epoxy.
His experience is that all epoxies have some form of blush (even BoatCoat), but it is not necessary to remove blush if a wet on wet application is used. In the summer that may be after 2 hours and in winter may be after 5 hours. Blush can be removed by washing with just water, then need to sand for a bond. Sanding is not needed for a wet on wet application. Ross will work to 2am if necessary to get the correct wet on wet application, in preference to having to remove blush and sand. Also, wet on wet gives a better bond.
Always be accurate with quantities and always mix well. Epoxy failures are always either incorrect quantities or not enough mixing.
Filler. Uses West Sytem 410 Microlite sanding filler for sanding and fairing locations. Also thinks the West System structural filler is a better product as it has fibres and has better non-sag qualities for less filler. The BoatCoat filler is very rough on edge tools.