Jumping around a bit I started to look at the lifeboat davits. Not a lot of info on the plans except they are Welin Mclaughlin and not much on the web, have done a hand drawn sketch from photo's on the Cervia site to give me some templates to work to. I intend to make them from styrene with a bit of discreet reinforcement to stop the arms twisting. The drawing is showing the tops of the arms a bit too thin, I will need to beef this up when building.
Baldric,
About 40 years ago I started S.T.Cervia from Vic Smeads Drawing at 1/4" -ft as a free plan, I progressed as far as getting the bulkheads and frames made and decided that it was too small so redrew it to 3/8" -ft which turned out the best idea as it is now powered by a Scotch boiler and a Stuart D10.
Like you I found it difficult to get any info on the Davit but was fortunate enough to have a cousin who was the oiler on the Waverley ( John Lees )and when she was laid up in Glasgow for the winter I was able to take some sketches of the Welin Mclaughlan davit fitted
to her.
I have had a search for my sketches but after 2- house moves , no luck but here are 2- pics of the davit that I made using plastic card and they are still strongly fixed after all the years , possibly need re painting.
I hope that they are of some help to you.
George.