Anonymous wrote:

I've been trying to keep out of this thread on line, but perhaps I should make a couple of comments here. 

Slieve, thank you for jumping in. And I did get the drawing, sorry for not responding sooner.

To answer your point about the pros and cons of ageing and sailing, I have investigated the possibility of keeping my existing rig, especially with the sails and spars being in excellent condition. However, the task of bringing all the lines back to the cockpit would be no small project. I would need, as a minimum, blocks on the tabernacle, as the deck steps down quite a bit near the mast foot, there would be organisers on the deck, maybe a 4 and a 5, clutches and jammers and not least, a winch or two. I had single line reefing on my last boat and it just didn't work very well. As well as taking a long time, it would be expensive.

I have the Easier Rigs book, which i believe was what attracted me to junk rigs in the first place.

Whilst you have convinced me that the SJR is probably the rig with superior performance, the Johanna plan gives the best compromise in terms of mast siting, stronger hull, doesn't block the cabin entrance so much, there's a perfect little area right in front of the deck slope.

If I'm doing this, I plan to get most of it done this winter, then spend the season playing with it. I'm very lucky that my winter storage is walking distance from the house and it is also an industrial shipyard so I might even be able to get the tubing through them. There are certainly lots of welders on site and although I myself have a TIG and MIG machine I'm not the best at it.

Thanks again. I'll obviously keep you updated.

The Plan B...

No need to take shelter, Slieve, I agree with you 100%:

Any project where boats are involved, takes twice the time.

Upgrading an existing rig makes much sense to me for anyone over 70.

The fastest conversion to JR that I did, was to Frøken Sørensen. I bought her in 2012 and hoisted the new sail in 2013. Converting Ingeborg’s rig took twice the time, from 2014 to 2016. She will be my last boat. I am more than happy that I finally squeezed in three outings in her in August, until the autumn set in.

Now, it is still legal to dream...
The Sabre 27’s profile is quite similar to my Alo 28, Johanna. Johanna even had a lee helm with her Bermudan rig, and her long trunk cabin forced me to design the sloop JR with 5.8m long battens. Her remaining lee helm in light winds was tolerable, and I would say she sailed very well (JRA Mag. 44, p.18).  However, her single broad sail caused quite some weather helm on a broad reach in a good breeze. As a possible plan B, I sketched in a little mizzen, but in the end, I found that for my use, the sloop was good enough.

Still, now I have tested a yawl alternative on that Sabre. As you can see, that little 3.5sqm jigger will move the CE over two feet aft of the CE of the junk sail alone.
Lots of work with that extra mizzen, but at least, installing the main mast will now be easy.

Cheers from the safe position at my keyboard,
Arne

Andrew wrote: ...I've done some preliminary work on the CLR and CE which is well out of my comfort zone.

You really don’t need to do that. If your boat handles satisfactorily with the existing rig, then find or make a reasonably accurate drawing of the existing Bermudan sailplan and determine its CE. Then superimpose a scale drawing of your chosen junk sail so that its CE coincides (on the same vertical line) with your existing Bermudan CE. (The CE of the junk sail will normally be on a vertical line which passes through the midpoint of the boom, near enough).

Now that the two sail plans coincide in terms of CE you can expect the handling (lee helm/weather helm) of the junk rig to be about the same as the bermudan rig. Experience has shown this to be the case with cambered junk rigs.

Now, this will show you where the mast has to go, depending on the type of junk sail you have chosen.

You will have discovered that different junk sail planforms have different amounts of “balance” – the percentage of sail area ahead of the mast. 

This is where you can experiment, on paper, until you find a planform which puts the mast where you want it to go. As David pointed out, the extremes are the Weaverbird wingsail type with ultra low balance, which puts the mast as far forward as you could go, - the SJR with its ultra high balance, which puts the mast about as far aft as it can go - and a range of “normal” HM and Johanna-type junk sails which can be found which will put that mast anywhere between these two extremes.

Summary: determine the existing CE. Find a junk sail planform, scale to the same sail area and fit it to the existing CE.  Choose the type of junk planform which matches both the existing CE, and the desired mast position.  

I hope this (not to scale, and slightly exaggerated) drawing explains how junk rigs of different balance give you a range of possible mast positions, with the CE matching the original  bermudan CE. 

This is not rocket science, it is merely geometry.

… use the existing mast and halyards to put the new mast in position, then de-rig the old mast and use the new mast to unstep it.  That has been done before, successfully, and it is a very good idea.

Hi Andrew, I agree the being able to use the forward hatch is a great feature on the Sabre 27 and in designing my installation I retained that feature. It did mean positioning the mast in the deck area immediately in front of the doghouse as had been done before on the boat fitted out by Sunbird Marine. However, this position is a bit too forward according to the PJR book and caused me problems as described later.

The sailplane used on the boat from Sunbird Marine (Sunbird 80's rig as illustrated in PJR) appears from photos to have an AR of 2 of greater with the sail is sheeted to a traveller on the bridge deck by the companionway as per usual arrangement for the BR rigged Sabres. In conversations with  Robin Blain he explained that the boat initially  suffered from extreme lee helm which was corrected by raking the mast aft 3 degrees. I also raked my mast aft by the same amount to meet the PJR recommended CE position of the sail relative to CLR of the hull. However, as mentioned in my earlier posting my original flat cut HM sail AR1.5 batten length 5.5m generated to much weather helm when off the wind which was corrected by recutting the sail, AR 2, all battens & Boom 4.2m. The mainsheet blocks are attached to a bridle across the transom. The CE of the recut sail coincides with that of the BR sloop.

I had considerable freedom in the fitting out of my boat because I was starting from a bare hull & deck moulding which had been stored in a barn for 20+ years by the original owner and  was in 'as new condition' according to the pre-purchase survey. No work had been done by the original owner mainly due to business commitments.

To distribute the weight towards the centre of the boat  I positioned the water tanks (2x 62liters)  over the bilge keels, as opposed to fitting a 120litre flexible tank forward as per the conventional Sabre arrangement. I thought this might compensate for the compromise with the mast position and associated weight more forward than ideal.

Further, I was able to move the heads compartment aft to starboard besides the companionway taking advantage of the offset companionway.  This arrangement enabled me to create two full-length single bunks forward with an infill panel to convert to a large double berth which is our usual set up. I also repositioned the anchor locker bulkhead further aft immediately in front of the mast to strengthen that area. The anchor locker  drains overboard.

I do have an ongoing issue with the forward position of the mast which with my current anchoring set up which makes my boat too bow heavy and negatively affected the motion of the boat upwind in anything but smooth water.  I am currently using an all-chain rode which together with an anchor totally 100kg+. Last year, to reduce weight up forward, I tried a rope/chain rode but just didn't feel secure overnight and the amount of scope required was problematic if there were other yachts at the anchorage. I'm now planning to move the chain locker aft and directly above where the head compartment is located for the conventional Sabre 27 layout.

You commented that you're  on a tight budget, so was I, which accounts for my taking 15 years to complete the fit-out! I hope your project can be completed sooner. I've uploaded a photo to give a better impression of the layout.

Best wishes, Frank

Anonymous wrote:

Hi Andrew, I read with interest your intention to fit a Junk rig to a Sabre 27. I fitted out, from a bare hull, a Junk rigged Marcon Sabre 27, twin keel. To my knowledge my vessel was the second Sabre 27 with a junk rig.