Friday 25 January 2013

Working on the hull: raking, hardening the caulking and re-caulking where necessary; sanding, priming and paying-up the seams with red lead putty.

The seams after raking and the caulking has been hardened-up. The caulking is in good condition generally, there were a few spots that needed new caulking such as the garboard.


Port side is being worked on.
Progress with Zephon is good.  The target of getting her in the water for the end of April is looking achievable and the boat is starting to look great.  I am very pleasantly surprised with the overall condition of the hull which is very good. The seams are fine and most of the caulking is in very good condition. Zephon is caulked with cotton and even after some 60 odd years it still looks like it was put in yesterday!

I have re-caulked the stem and a small section of the garboard plank. I hardened-up all the seams and then primed them with Jotun pink primer. Once the seams had been primed I then used a long board (a 4 ft flexible board with handles that enables the hull to be sanded fair. Sorry I forgot to take a photo).  

With 60 grit attached to the long board I sanded the hull. It is important to sand at 45 degrees across the hull in both directions. This ensures that no unfairness is put into the shape of the hull. The angle of sanding will need to become shallower towards the stern of the boat as the compound curve of the hull increases. 
A graving piece on the stem.
Me paying-up the seams with red lead putty. It has been a bit chilly.

Once the hull had been fully sanded I then painted the hull with pink primer and then payed the seams with red lead putty. Needless to say red lead is highly toxic. I mix my own red lead into glazing putty. The ratio is simple; I continue mixing red lead into the putty until it is the same colour as the red lead in the tin. When mixing red lead always handle carefully. Place the red lead powder into a small amount of linseed oil and stir into a thick paste before kneading this paste into the putty. Mixing the powder with oil stops any red lead dust becoming airborne (wear a dust mask to protect yourself from inhaling red lead dust when mixing with linseed oil and wear gloves when handling as lead is easily absorbed through the skin).

Red lead is a traditional boat building product and in my view the best way to stop the seams as it keeps the putty flexible and so prevents the putty from cracking. If done correctly the payed-up seams should be good for years and years.



Port side seams all payed-up. Now to start on the starboard side!

No comments:

Post a Comment