Anonymous wrote:

Andrew, congrats with you new boat.
Converting it to JR is both easy and difficult. 

Hey, thanks Arne. That layout looks very similar. Unlike the previous boats it seems I won't have a problem with the forward hatch. It might slightly mess up the sleeping arrangements although luckily there is a big double berth in the main cabin.
I was thinking maybe I could use the tabernacle to raise and drop in the mast, into a fixed tube. I believe there's someone who's done that.
Is it usual, with a twin keel, just to glass a mast base into the bottom of the hull?

My current mast is exactly 10m from deck level. I was expecting a little taller. Does that sound about right  for a JR? If so, I will hope to do what David was proposing and use decreasing sizes of aluminium tubing.
I will see if I can find a scale drawing of the interior and compare it with your drawing.
Thanks again.

Hello again. I'm sure some people may think I'm "crying wolf", but I have found my forever boat. After a couple of false starts. There was the Yachting World 5 Tonner, which I bought, desperately hoping that it would lead to a local mooring allocation. Turns out it wasn't necessary and she proved to be too difficult and heavy to sail, gloomy down below and with all the looming maintenance of a 1947 wooden boat. Then there was Minxie, the 20' Hunter Medina. She was too small and tippy, with 3 dogs and grandkids, impossible to sail with a cramped cockpit. She is going to her new owner on Monday.
Minerva came out of the blue, as boats sometimes do. Advertised as a new Yanmar engine with basically a boat thrown in for good measure. She had been standing on the hard at Falmouth for a few years so was not the most attractive proposition but after a basic pressure wash she has come up lovely. I am absolutely over the moon with this vessel. She is so roomy for the length, very beamy in the cockpit and the cabin, double berth in the main saloon, huge forepeak, oven, sink, self steering windvane, oh and did I mention the new engine, 50 hours on the clock!
The first voyage from Falmouth to Fowey was a dream. She is solid, predictable and very stable.
A big thank you to David Tyler for suggesting the Sabre, I had never come across them before but she ticks all of the boxes and more.
I have made a new sail cover but I used offcuts of canvas (hence the different colours) so it didn't really cost anything and I won't mind ditching it.
At the age of nearly 75, this will be my last boat but I couldn't be happier.
Now I really can throw myself into planning a conversion without the doubts or hesitation I had with the previous two. 
I'm guessing the Sabre 27 is similar to a Westerly. She has twin keels, weighs in at about 3000kg.
I have joined the Sabre association but I don't believe there is a Junked example.
I think maybe the biggest problem might be that there is quite a narrow access to the forward cabin, where the mast is likely to be, between the heads and the hanging space.
I'll probably go for a SJR but that may put the mast position right where the entrance to the heads is.
Anyone come across a converted Sabre or 27' Westerly?
One benefit will be that if the mast can be dismounted easily I can then go to Looe for winter storage, which involves going under a low bridge.
If the mast position could be retained, there is a very substantial tabernacle which I may be able to make use of.
Thanks in advance for any advice.