The internal plan of a Top Hat 25
MK 0
The cold moulded model from 1963, four 3mm laminations laid up with resorsinal glue on mahogany stem and main frame with laminated mahogany floors.
MK I
Baker built MK 1's. Baker came from Royal Brighton Yacht Club in Melbourne to run Fibreglass Yachts in NSW. These MK1's were built from around 1969-73 (although exact dates are hard to pinpoint) and had a hand laid up Glass-reinforced plastic hull and are therefore considered to be a little stronger than the latter models. The MK1's did not have a sliding hatch above the companionway as did the timber models but had a "key-hole" entry (semi eliptical shaped cabin top above companionway). Above sat the main sheet traveller, some of which were a raised stainless steel tube following the contour of the cabin while the latter ones were a conventional horizontal traveller. The cabin profile had a step down to the mast the main sheet whinches mounted on steel struts and sometimes had a double spreader rig. For accommodation the original standard timber boat had four berths, a centrally located galley and a large chart table as Illingworth placed great importance on the role of the navigator, whilst with many of the MK1's the interior layout was often left up to the individual. However, some were built with an enclosed head, vee-births forward, central galley and settee berths port and starboard.
MK II
Formit Fibreglass in Wyong took over Fibreglass Yachts and continued to produce the MK1's. Apparently Mike Garrett of Formit asked a Sydney Naval architect to improve the cabin layout and look at the boats sailing lines. The cabin layout was modernised but the Naval architect couldn't improve Illingworths original underwater lines. The new MK2 was released in november 1976 and had a relocated forward hatch, anchor well, wider and fatter cabin top and streamlining. A lock-up toilet was still available but a MK2 A appeared with a toilet forward and an oilskin locker!
MK III
The MK3 appeared around 1981 and was usually characterised by a single sleek tinted plexiglass window on either side of the cabin. However the traditional windows of three per side were still available and could be specified as required.
Two interior designs were available. The A is the racing version with the head between the forward bunks and a hanging locker in the main saloon for wet weather gear etc.
The B is a full lock-up toilet version with a smallish but manageable compartment with toilet, hand basin etc, aimed at the small family cruising market. A single deep cockpit locker was provided on the port side which allowed for a good sized quater birth on the starboard side.
The basic hull remained the same with the near full length keel and a keel hung rudder. 1234 kg of lead in the keel and a displacement of 2580 kg, makes a safe ballast ratio of 48%. The hulls were gun sprayed in two halves, joined down the middle and then lead is poured into the keel from the inside.
