KeithAug

Planking the stern would have been difficult. I think your alternative plan is the right way to go

Keith - your interpretation of photos is impressive. I think my eyes need an overhaul.

After a bit of a layoff I am back at it. Somehow I picked up an unusual lung bacterial infection that required 3 rounds of different antibiotics to knock it on the head. The last lot seemed to do the trick and i'm now on the mend. I have been doing a lot of work on the hull lines drawing. You will probably recall Mr Rutherfords comment to the effect that the original lines were not available and the lines drawing was produced from a scan of the hull. I don't know in detail how scans are done or indeed the details of the curve fitting programme used to generate the lines. Clearly though the small number of scan points has presented a challenge the curve fitting programme. Having printed out the the previously mentioned drawings at 1:24 scale on A4 sheets i joined them together paying particular attention to alignment and overall dimensions. The breakfast bar came in quite handy (despite some protests). I played the illness card which seemed to have the desired effect. Looking at the lines drawings prompted a few questions. On the transverse sections at section 4 near position "A" there is a slight curvature. On the various photos I have the hull seems quite flat at this position, much more like frame 5. On the horizontal sections near the stern the lines at points "C" and "D" seem to have odd local curvatures and I guessed that this was down to the curve fitting programme struggling with lack of data. Rather than accept the lines I decided to check the transverse, horizontal and longitudinal sections against one another starting by plotting the transverse section on top of the horizontal sections. This revealed a number of discrepancies. Near the stern the 4'WL plot deviated quite a lot from that line on the horizontal plan. The orange line below shows the original plot line while the new line below it is the line generated from plotting out the transverse sections. Smaller deviations were also revealed on the 6",8"and 10"WL plots, here again the orange lines are the original and the black lines are the projections from the transverse plots. There were similar (but smaller) discrepancies towards the bow. I then plotted the longitudinal section back on to the transverse sections which revealed discrepancies at the rail. The pencil lines show the runs of the rail and deck edge. While none of the discrepancies were major I decided the best way forward was to get the plan, side and frontal lie drawings in agreement before generating the hull sections for build purposes. This is now complete and i can start generating the hull transverse sections corresponding to the frames on Cangarda.

Great detail on the boiler but will it be visible?

Lovely little boat Gary. looking forward to it.

Denis - I bought an old mahogany table which had worm in some of the soft wood framework. It proved to be low cost and very good quality wood. You might want to consider getting some old mahogany as it is much better quality than the modern stuff.

What wood are you using for planking Dennis? Are you double planking?

Eberhard - I am surprised they came out as well as they did with solid wire, but as I said I only noticed it in the one close up shot. I find small electrical motors from broken toys are a good source of very thin wire.

I wonder if it is a line for an anchor marker buoy. Attached to the anchor with a buoy on the deck. Drop the anchor and throw the buoy overboard so the buoy marks the position of the anchor. This lets other vessels know where the anchor is so they are not inclined to drop there hooks on top of it.

The suck it and see approach is also valid, you will probably find that just "doing it" produces fully acceptable results.

Nice detail Eberhard. In the second to last photo the stays from the mast to the deck abreast the smoke stack seem to have some curvature but this isn't obvious in the other images. Is it a photographic effect?

Thank you Rob.

Sorry Andy - memory failed. Mac's don't seem to have that capability, unless they hid it somewhere that wasn't obvious.

Gary - Is that a Mac print programme?

Grant - I had a look round the local print service companies which seemed to offer prints uf up to A0 in size (smaller than I need). They were not exactly cheap. I think I can manage the accuracy issue and at least if i print at home I can avoid a car journey. Yorkshiremen are noted for being careful with their cash and my wife says I am an extreme example. Her lifetime mission has been to compensate for my behavior and in that she has proved to be a master!

I spent a few hours of today working out how to print the hull lines at 1:24 scale. The lines PDF file supplied by Tri Coastal Marine was drawn at 1/4" = 1' (1:48) so I needed to print them out at 200% scale. Both the standard and Safari print programmes on the Mac seem to have limitations on how they print scale copies across multiple sheets so I had a look for an alternative. A bit of research led me to Adobe Reader (free download) and this proved to be much more user friendly. The lines drawing was imported into Adobe reader in PDF format. This opens up the following screen. Clicking the print icon then pulls up the following screen: Selecting the "Poster" option (A) enables printing across multiple sheets. Selecting the scale (B) allows the PDF to be printed at the desired size and also defines the number of pages that the image will be printed over. Selecting cut marks (C) instructs the printer to print alignment marks on the printed sheets. This significantly eases the assembly of the printed sheets into a composite picture. The image at point "D" adjusts automatically to show how the image will be printed across a number of sheets. In my case i was using and A4 printer and the image was printed over 55 sheets. Fortunately a few months ago I invested in a "Big Tank" inkject picture so printer costs were not really a consideration. I used the same procedure for printing out the other 2 PDF's provided by Tri Coastal Marine.

Roger - For a while I worked in the Chemical Plant Design Office of British Nuclear Fuels (Nuclear Reprocessing). Of necessity at times I got involved in the design of reprocessing plant pressure vessels (and pipework). Because of their often unique shapes and restricted geometries the pressure vessel code rules were frequently inapplicable. For safety assurance reasons we often had to design the vessels from scratch using finite element analysis. For the services pipework we did however use ASME codes and their British Standard equivalents. My early career was spent with Rolls Royce at Derby (1969 to 1978), partly in the aero engine design offices. The nature of the materials, the design loadings and extreme environments made code based design rules inapplicable. I agree however that in many instances (including shipping) the code based design approach has a lot of merit. The watch out of course is to avoid extrapolating the code to cover circumstances beyond its intended use - as was the case with the Heathrow runway light.

Roger, Interesting - another example of code based engineering. I once had to investigate an incident with a plane that landed at Kansai International Airport with a 2kg Heathrow landing light retaining ring embedded in its hull (but fortunately not the pressure hull). Kansai were not impressed! The retaining bolts for the ring had all sheared off allowing it to become loose and presumably it had been flipped out of its seating by the nose wheel on take off. During the investigation it became clear that the code had first been formulated some 50 years previously and the calculations within it were based on the wheel loadings of a DC-3. The wheel loadings of Boeing 747's are somewhat higher than those of a Douglas DC-3's. Some codes now allow for engineering analysis in lieu of historic precedent but I accept this isn't always the case. I wonder when the 1ft rule was first formulated and what specific geometries and loading conditions it was designed to accommodate. However "The Rules is the Rules" as they say. At least I now know how wide to make Cangarda's porthole strake = porthole diameter plus 2 feet.

Thank you Roger. I had picked up some of the detail but not all of it. I don’t have the 2010 paper so I will look it out. I have some of the build photos from her restoration so I was aware of the welding and fairing. As I mentioned earlier I was a bit surprised to see that thicker plating had been used on strake that encompasses the portholes meaning that the hull isn’t entirely smooth, so this should add a bit of modelling interest. I think there are still a couple of riveted hull steam powered vessels operating sight seeing services in the UK.

Impressive metalwork, winches and booms. I would have loved to have seen more of your techniques.

Yes Bob the language barrier strikes again: Brightwork also known historically as "bright work" refers to the exposed and varnished wood or metal work of a boat.[1] The metal is usually brass or bronze that is kept polished, or stainless steel, which requires less maintenance.[2]

Early post restoration photos appear to feature what i would recognise as a modern representation of a traditional block.

They are great Rick. I have spent most of this evening studying and organising the photos, quite an enjoyable evening, particularly when I suddenly realise what an obscure image is ( eg the steam whistle hiding in the canvas). Could you please pass on my sincerest thanks to everyone who has facilitated your visit. A lot of other MSW members appear to be enjoying going through the images so that’s another accolade for your efforts. Have a good day.

That's very interesting Roger. The one obvious anachronism in this approach is the fitting of the stabilisers. To me they look quite out of place on this style of hull. Bob. The brass isn't in a great state which in my book is a crew duty. I don't know whether Cangarda was built with traditional wooden blocks but agree stainless steel and plastic look out of place.

Spoil sport, I am deflated.