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Latest updates on the 1942 Motor Gunboat MGB 81

May 30, 2018

Over the past 5 weeks, we have brought you a series of short videos on the refit and restoration of the 1942 71.5ft Motor Gunboat MGB 81. For those of you who have missed then you can watch them all here.

  • Engine Removal – Watch Here
  • Engine Removal Timelapse – Watch Here
  • Part 1/5 – Laminating, Spiling & Shaping the Hull Frames – Watch Here
  • Part 2/5 – Fitting the Hull Frames – Watch Here
  • Part 3/5 – Fitting the Stringers, Longitudinals & Bunk fronts – Watch Here
  • Part 4/5 – Fitting the Bunks & Webs – Watch Here
  • Part 5/5 – Fitting the Flooring Structures – Watch Here

We now also have a new webpage dedicated to the refit of the MGB 81, here you can read all about her history and her help in the D-Day landings, how she engaged five E-Boats in Lyme Bay, when she was arrested by Customs officers at Shoreham, whilst in a smuggling operation, and much more.

We will also be posting all of our latest articles here, along with all of our videos showing every stage of her refit.

Portside hardwood rub rail

Rub rails cover a boat’s hull-to-deck joint. They are cosmetic in that they generally hide the seam and fasteners connecting these two parts, and though rub rails are no substitute for experienced handling or the proper use of fenders, they do provide protection against abrasion and mild bumps from pilings and bulkheads. So they get worn and eventually need to be replaced, especially if the boat lives in a commercial environment.

They were formed in the same way that the hull frames were fashioned, only this time it was a minimal bend in the wood and only 3 layers of iroco. After the glue had set, the rough shape was formed and it was fitted in place, scarph joints were used at either end and fastened with coach screws into the beam shelf internally. It was then planed and sanded down to match the original curve. Within a couple of months of her being outside and back on the water, the new rub rail will discolour to the grey appearance of the older sections at either end of the repair.


You will recall the myriad of newly laminated frames which were recently replaced and glued into position transversally in the interior you can read about how the frames were fitted here or watch Part 2/5 – Fitting the Hull Frames, in our series of videos above); to add strength, countersunk pilot holes were drilled every 8 inches or so and obviously following the line of each frame; subsequently a 3.5 inch silicon bronze screw was secured into each.

Obviously drilling a few hundred holes in the bottom of a vessel isn’t the best look or great for keeping her watertight; as a result, we sanded back the immediate surface areas, applying three layers of 300g cloth with epoxy resin over each screw head followed by a final layer of (green) peel ply which brings the by-product of epoxy curing – amien – to the surface. As per its name, the green peel ply is detached leaving clean surface for application of filler and/or paint.

Just to confuse the reader, the green remnants around the edge of the patch in the series above is actually is the gelshield which was used on the bare hull glass laminate which protects the wood laminate underneath! The rest of the green patches are the peel ply waiting to be removed.

After green peel ply has been removed the patches are again sanded smooth ready to accept an epoxy primer and lightly sanded back and primed for the second time before an initial patch of antifoul is added prior to a new coat of antifoul across the whole underwater section just prior to launching.

Transom Repairs

Her aft port corner was damaged which has now been filled and sanded back ready for a coat of primer before we repaint her hull and topsides.

As you can see, sanding her back is a big job!

New Engines

Back in December, you may remember we removed the 3 MAN 835hp engines. In late April we took delivery of the 3 new FPT C13 Mermaid Marine 825hp diesel more fuel-efficient engines which are also lighter more reliable. Fitting new gearboxes takes place in order to work out the positioning of the new engines prior to the fabrication beds, which is being undertaken by second-year apprentice, Steph Jung, cutting out the brackets with an oxy-acetylene torch for the first time.

Trials are scheduled in mid-2018, after which she will be on show at the Portsmouth Historic Dockyard along with other renowned historical vessels together with HMS Victory, HMS Warrior and the Mary Rose.

Outstanding jobs still include;

Helm & interior

  • New engine displays & controls
  • Steering system
  • AIS system
  • Installing glass deck lights

Repairs and Paint

  • Complete repaint of vessel topsides, deck, antifoul and coach roof
  • Deckhouse repairs
  • Deck hatches repairs

Engine Room

  • Fitting of new FPT C13 825hp diesel engines
  • New gearboxes
  • Installation of new exhaust system, fuel system and seawater cooling system
  • New shafts and prop
  • New batteries
  • Installing engine room fire alarms
  • Servicing and upgrading hull valves and fittings
  • Servicing of all seacocks

Progress and updates on this project can be followed on our website here or register for our monthly eNews blog here.


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