LIGHTSHIP CORMORANT / LADY DIXON - Chapter 124

Well Simon has had a go with the compressor and nail chisel gun. “Quite arm-aching” he reports – well I did warn him. I think he should import some labour for this particular job. If he can find someone who could do two or three hours on two or three days per week (even Samson couldn’t last more than three hours at a stretch !) it might all be ready for spraying when the warm weather returns next Spring. I assume the surfaces have to be dry when sprayed.

    Meanwhile a spell in dry dock will be better during warm, dry weather, so will probably take place after the below deck spraying next year. Looking at those composite pictures in the 14 November post, I was wondering if a normal tide will lift the ship out of that deep mud hole. No problem. I calculate that the mud hole is about 5ft deep and the difference between high and a low tide is over 15ft at Hoo.

   So, something to get on with – the stanchions around the deck are a mixed bunch (Photo 1241). 

There should be about 50 of them, but 20 or so are missing, 15 need replacing and a dozen are OK. Simon is thinking of steel boxes fabricated with base plates (Photo 1242). 

    If all surfaces were true and in good condition that would work, but all that welding would be expensive.  Easier to fabricate, adjust and fit would be angle brackets (Photo 1243) and they would be a lot cheaper. 

     On the historical side, I am trying to establish where Cormorant/Lady Dixon sits on the timeline. I am sure she is one of just a handful of ‘composite’ ships still afloat (Cutty Sark is ‘composite’ but not afloat). She may also be the oldest Irish Lightship still afloat, but I will be happy to hear of other contenders for the title.

David

LIGHTSHIP CORMORANT / LADY DIXON - Chapter 123

I think the mystery of the hull lining material has been solved.  Suggestions have included sprayed cork and glue, but Simon reports that it is very hard and the small piece he was able to prise away does look like stone/cement.

   To sum up - Portland Cement became popular in the mid-1800s. Many builders of iron vessels in the late 19th or early 20th century poured cement in the bilges as a protective coating. Compared to the best paint available at the time, cement served far better in protecting hulls from the corrosive effects of sloshing bilge water. I found all this on the Internet - yes my broadband is back again after 6 weeks!! 

   The clinching item came from the 1880 Specification for Irish Lightships, which stated “The inside of the vessel, as high as the sister keelsons, to be coated with best Portland cement; to be flush with the limber holes, and to be laid thickly in the throat of the frames, and to cover the nuts of the bolts." 

   I cannot fathom what ‘flush with the limber holes’ means, let alone ‘in the throat of the frames’, although I do know that a limber hole, 3 inches in diameter, was cut on each side of the keelson and a galvanized chain, 3/8 inch diameter, was passed through each limber hole for the entire length of the ship. These limber holes allowed bilge water to drain to the centre of the ship where it was pumped out from time to time and the chain kept the holes free of detritus (Photo 1231).

I hope I have got the diagram right – perhaps you naval chaps would put me right if necessary!

David

LIGHTSHIP CORMORANT / LADY DIXON - Chapter 122

It’s now 6 weeks since my phone and broadband went out. I am sitting in my Morris Minor in my neighbour’s driveway sending this – with her permission of course!

I thought this week I would amplify what Simon has been finding down in the bilges.  First of all a diagram to show where he actually went (Photo 1221). I think I have got the scale of the figure about right – the headroom down there is about 3ft 6ins.

Next is a diagram to show where the camera was pointing for each of the three shots (Photo 1222). The fresh water tanks have been highlighted in both diagrams.

The first shot (Photo 1223) is of that bow area which I showed in the previous post, but closer to it. 

No damage or water ingress is apparent and Simon is still not sure what that multi-coloured material is on the sides. Any ideas?  He will have to be a little bolder with his scraping tool to get a good sample – not too bold of course with the Medway just outside!!

Then he turned around and took a shot of the two lines of fresh water tanks, which altogether hold 7 tons according to the plans (Photo 1224). 

 It would be interesting to know if they are empty or not.  I suppose that tapping the sides might give us the answer – not that I would want to drink from them!!

 The final shot is down the port side of the ship showing the tanks and the steep line of the hull as it sweeps down to the keel (Photo 1225).

It all looks pretty dry down there.  Note that the tanks are set on timber blocks, as can be seen on the plans in photo 1221.

Doesn’t it make you want to crawl along those ‘corridors’ and see what else can be found?  Next time I visit him ……….
David

LIGHTSHIP CORMORANT / LADY DIXON - Chapter 121

My aim over the past week (apart from trying to get my phone and broadband reconnected !) has been to pinpoint that area of damage at the bow. It has been a fascinating exercise – am I turning into a Nerd?  I started with one of Simon’s photos taken by him from his canoe. Although the bow is not actually in the photo, it was the only shot showing a full-on side view (Photo 1211).

   Now this shows a long, slim craft (hull in need of a lick of paint) with an extensive superstructure. Next I took the 1943 blueprints and pasted the hull from those onto the photo, adding bits from other photos to complete the bow (Photo 1212).  The waterline is in red. Chubby isn’t she?

    Emboldened by this, I did the same to the bow, pasting a blueprint extract onto a photo of the damaged area (Photo 1213).  

 This shows that the main damage area – along the bottom edge of the bow doubler which I have outlined - is where the lower deck meets the stem (?) at point A. The waterline is again in red and the ‘mudline’ is in brown – so that is quite a trough she is sitting in!

  Quite fortuitously, Simon discovered a trapdoor in the lower deck, up at the bow and went down exploring. He took a good photo of the inside of the bow/prow, which shows I think that girder in Photo 1213 curving up towards point A along the centre-line of the ship (Photo 1214).

The damaged area must be further up than A and off to the right where I have no doubt that a similar girder curves in a horizontal plane into the stem.  I have tried to indicate that area with B, but it will be behind that cross strut. He needs to crawl a bit further forward next time and photograph what is right up at the front.  One reassuring thing is that there is no evidence of water ingress anywhere.

   The horizontal beam I mentioned can be plainly seen (or can it?) in the outside shot taken by Simon some time ago (Photo 1215).

   While he was down there, he turned around and took a couple of interesting shots of other things lurking, but they will have to wait until next time.

David