Tuesday, November 29, 2016

New Video of Bolger Hope

We are now getting some time up on the Phil Bolger 'Hope' I built back in 2003. Here is a link to a youtube clip shot on Sunday November 27 2016

Damaged piston and the replacement, complete with new rings

After having suffered an engine seizure due to salt water in the cylinder, David Lillistone (son) and I carried out an overhaul replacing the piston and piston rings, exhaust valve and seat, plus a multitude of other components. In addition, I had a new bronze propeller made by Austral Propellers, with consultation and calculation provided by William Olds and Sons (Olds Engineering) in Maryborough. The service provided by Olds Engineering was exceptional, and they acted on my behalf in dealing with Austral. http://www.olds.com.au/

Three generations of the family worked on the engine overhaul...

The engine is now starting to be run-in, although I believe she will continue to improve for a long time yet. The original propeller was a 12" x 10" re-pitched to 12" x 8". The blades were of the Yanmar pattern, but the replacement is a 12" x 8" from the start, with about a 55% disc- area ratio.

Original Yanmar-pattern propeller....

....and the new Austral prop supplied by Olds Engineering

Performance is continuing to improve with use, but the boat has gone from a top speed of 6.1 knots/7mph to 7.3 knots/8.4mph. That is at maximum engine speed of 3600rpm, but at maximum continuous of 3400rpm continuous speed falls back to about 6 knots/6.9mph and at my preferred cruising speed of 2800rpm, we run at about 5.5 knots/6.3mph. Those 2800rpm speeds are quoted from memory, but I have got them recorded somewhere.

When we are bird-watching, or just cruising the shoreline, or favourite engine speed is 2000rpm - the engine is like a sewing machine and the boat runs at a very pleasant 4.7 knots/5.4mph.

Saturday, November 12, 2016

Up-date - Lugsail Yard Parrels

In my previous post, I presented a hand-drawn illustration of my preferred method of setting up a yard parrel (in this case a Snotter).

The drawing shows the parrel/snotter (drawn in red) simply slipped over the mast and the halyard, but in the text I mentioned that the parrel can be attached to the rolling hitch which secures the halyard to the yard. For the entire time - at least three decades - that I've been using this parrel system, I've always secured the parrel to the halyard or the yard, but when I was preparing the drawing, it occurred to me that it may work simply slipped over the mast and the halyard.

Well, just two days ago I did a rigging job for a man who had built a beautiful Paul Gartside-designed lapstrake (clinker) dinghy. In the process I tried out the method as depicted in the above drawing, and although it worked, the parrel had a tendency to hang-up on the mast due to friction between itself, the mast, and the halyard. I quickly re-rigged it so that it ran under the rolling hitch, and everything was fine.

So lightly attach the snotter to the yard or the halyard where it is secured to the yard. That way, the parrel/snotter will lower positively with the yard.

Sunday, November 6, 2016

Lugsail Yard Parrels

My old boat setting a balance lug, with the yard snugged up against the mast

 A problem which many people encounter when using a balance lug, standing lug, or a Chinese lug, is arranging a method to hold the yard close to the mast.

Some designers advocate a method where the halyard is attached to the yard towards the heel, and then leading along the yard (and around the mast) to a pulley-block at the normal halyard attachment point.

The theory is that as tension comes onto the halyard, it automatically pulls the yard in against the mast. I've tried it, and (for me) it doesn't work. The amount of force holding the yard against the mast is small, and much more importantly, the yard is largely free to move forward and aft through a significant arc.

Here are two photos taken on a day when we tried it on my sailing canoe just for fun, and as you can see, it wasn't worth a cracker!

Yard with the normal halyard attachment point hanging aft by close to a foot

Halyard doing a very poor job of holding the yard close to the mast, even though the downhaul and halyard tensions were high.

Another popular option is to use a loop of line, bronze rod, or stainless-steel rod around the mast somewhat like a conventional mast hoop on the luff of a gaff mainsail. If you follow Jim Michalak's suggestions for a loop of line, it will work OK, but is prone to jamming when the sail is raised. You can confidently follow Jim Michalak's advice about almost anything regarding boats, but in this case I believe there is an even better way.

The metal ring method has problems in that it makes it very difficult to get the yard aft when lowering, until you can reach high enough to lift the yard off the hook which usually forms the attachment to the ring. If the sail is boomless, it may not be too much of an issue - but when a boom is involved, it is very important that the yard is free to move fore and aft while still being attached to the halyard.

The system I prefer is simple, light, and highly effective. Here is a drawing which should be self-explanatory. Click on the drawing for a clearer view.

The loop (shown in red) can be simply dropped around the halyard, or can be attached to the yard by the halyard rolling-hitch. Raising and lowering the sail is no problem, because as soon as the yard is lowered, the loop automatically loosens, and when being raised, the loop is loose until the yard reaches the raised position. If you need to reef, lower the yard to the required position, and simply re-tighten the lower end of the snotter (a.k.a. Yard Parrel) and the yard will be held snugly against the mast. No need to make it tight - just snug.

Below are two photos showing the system in use on a First Mate. In this case, we had the snotter line knotted into the halyard rolling hitch on the yard, but it isn't necessary - the system shown in the previous drawing is fine.

Blue line is the halyard, and the buff-coloured line is the snotter (yard parrel).

The system is simple, light, and reliable. I've used it for years without any problems.