No. 61 - February 1985

INSTALLING AN AUTOPILOT

Jacques d'Avignon (#595)

 

For many years I had been thinking of putting some kind of autopilot on "Iceland". I looked at many models and compared the specifications and prices. Finally this year I decided to take the jump.

 

While browsing in a very interesting store in Pointe Claire I came across an Auto­helm 1000, it was Spring, the price was right and the staff at Sailfast have a way of making you feel welcome.

 

To make a long story short, after thinking about it overnight, I decided to order the equipment. But before I did, I was told that Mike Nicol-Griffiths had one. A short phone conversation with him convinced me that it was worth it.

 

The installation is very easy if you follow the instructions. It would appear that the dimensions are quite critical. SO FOLLOW THE INSTRUCTIONS . . . . the unit itself is quite simple as you can see in photo #2 + 2A + 2B. [Note – photos were not included in the compendium]

 

Because the seat of the Tanzer is not thick enough, I had to reinforce it by bolting a piece of oak underneath; this explains the 4 screws that you see in photo 3. The center fitting is supplied with the Auto helm and is embedded in epoxy. Drill the hole through the seat AND the reinforcing plate underneath, mask the hole in the bottom with masking tape and then insert the fitting in an epoxy mixture. When you insert the fitting in the epoxy mixture, hold your finger over the bottom of the hole and the mixture will ooze out from under the masking tape spread on backing plate. In order to stop any sagging of the epoxy put MANY layers of masking tape on the bottom of the hole and let dry. LET DRY AT LEAST TWO DAYS, even if it feels hard after a few hours.

 

The wind vane installation is very easy, #4; here again FOLLOW THE INSTRUCTIONS. The instructions for the wind vane are not included with the vane but are included with the main unit. The installation of the small turning blocks used for the mechanical feedback from the main unit to the vane should be installed only after everything else is done.

 

Some accessories are available for basically any installation of an Auto helm to a tiller steering. They could also be obtained from the friendly Sailfast store, but with the type of installation I wanted, I decided to have my own bracket done. Out came the drafting instruments and a sketch was prepared with all the vital dimensions. A trip was made to Custom Fittings in Rigaud and in about one week the necessary bracket had been fabricated (photo 5). In my opinion this bracket could be used to steer the Queen Mary, but do not forget that the autopilot will put a lateral force of about 70 pounds on the tiller and you do not want to have the bracket bend. (Custom Fittings must have kept the drawings for this fitting so if anyone is interested it could be duplicated, there is no copyright or patent fees).

 

The electrical system is very easy to install. The plug and socket are supplied; they are heavy duty and waterproof.

 

If anyone needs extra guidance for the installation I am available for consultation for the price of a postage stamp.

 

YES, an autopilot is a luxury, but it permits you to not have to be at the tiller all the time. You can go down below to get a fruit juice, check a chart or do what­ever is necessary. BUT KEEP A LOOKOUT. The unit will keep a better track than you can do manually. When using the wind vane you can keep pointing very well. I found that running down wind the vane is too sensitive so I use the magnetic sensor.

 

 

ANTIFOULING, RUSTY KEEL, AND LOCATING DEPTH TRANSDUCER

Questions: from Bob Maguire (#2115)

Reply:    from John Charters

 

In August of 1983 when I purchased my new T22, #2115, from the Arlington, WA plant they applied Woolsey's "Vinelast" to the bottom for me. It has been moored in the waters of the Straits of Juan De Fuca since that date and should, no doubt, be in need of new paint by the start of next season.

 

This is a new experience for me since I have never applied bottom paint before. I intend on using Vinelast if I can find it or Neptune since I understand that these are popular paints for the waters of the Pacific N.W. I also understand that the biocide used in these paints is cuprous oxide and reacts with the iron keel if the keel is not properly primed. Can I assume that since the bottom paint was factory applied that the keel was primed and that I need not worry about applying Vinelast or Neptune over the old paint.

 

Please correct me if I am wrong but to apply bottom paint over an existing coat I should first clean the bottom of all organisms and algae, let dry and then sand. I am not really sure why sanding is necessary and how much sanding is necessary. If you would not mind giving me a few pointers on bottom paint application it would be greatly appreciated.

 

Also, do you have any suggestions on where I should install the through-hull fitting for a Signet MK 172 sounder. I will at the same time install a Signet knot meter and will take Steve Sandler's advice offered in the June '84 Newsletter and mount the through-hull fitting beneath the porti-potti starboard of the center line.

 

I look forward to hearing from you.

 

From John Charters in answer:

 

Let me answer your questions on bottom paint by first asking a few questions of my own.

 

How does the hull and keel look when the boat is hauled? That is, how much growth? Is the hull reasonably clean, with perhaps just some easily removed slime around the waterline? Or is there a lot of algae, barnacles and weed? Do you keep the boat in fresh or salt water? And how much rust is on the keel?

 

If, and I say, if, the hull is reasonably clean I'd be tempted to leave well enough alone, clean off the slime and try to get another year without having to re-paint. I might touch up around the water line with a thin coat of new paint, but that's all.

 

Which brings me to another question. How well did the Vinelast stick to the hull? There are many factors - no matter how scrupulously one follows the paint manufacturers' instructions on hull preparation - sometimes the paint sticks like 'you know what' to the blanket, other times it all peels off.

 

And if the answer to my last question is the latter I'd completely remove every trace of the peeling anti-fouling paint and start over. Following the manufacturers' instructions. Which in most cases will include washing the hull down with some sort of cleaner, priming with the recommended primer and re-painting. The second time around the paint generally adheres fine.

 

However, if the paint and hull cleanliness is somewhere in between, here is what I'd do. First, of course, is to clean the hull of all growth. Water and a brush, or if very stubborn you may need to use a bottom cleaner such as 'Lan-O-Sheen’ Boat Armor Boat Bottom Cleaner. (About $5.29 a qt.). Then I'd sand any areas where the paint has chipped off and generally smoothing off the hull, feathering those spots where the hull shows through. A smooth hull is a fast hull, what we don't want is the finished job to look like the craters on the moon: Then I'd give it one coat only, of anti-fouling paint. (More about my choice of paints later.) Making sure, of course, the hull is free from 'paint dust' before painting. Your paint manufacturer may have some specific suggestions on how best to clean the hull, if not a wipe down with the recommended paint thinner should do the trick.

 

If the hull was badly fouled I'd stop and think, perhaps asking other local sailors for their choice of bottom paint A paint that works well in one area, may not work at all well in another. But if you do have a lot of fouling after only a season, I'd sure suspect the paint you are presently using. I'd seriously consider changing brands. Beware: Not all paints get along with each other. Vinelast is a vinyl based bottom paint, and you should be able to paint over it with any other vinyl based paint, including International's 'Vinelast', 'TBTF' and "Micron". My first choice is Micron. In Canada the manufacturer markets 'Micron 25' which is suitable for home application. In the USA, you have a choice, 'Micron 22' suitable only for professional application, or 'Micron 33' for owner use. I believe your 33 is much the same as our 25, with perhaps a softer finish as you sail in warmer waters. Ask the manufacturer, or your local dealer.

 

Unlike conventional bottom paints, the biocides (International does not reveal the composition of this biocide, other than to state that it does not contain any copper) in Micron are in solution and as the paint wears new and fresh biocides are constantly being exposed. Conventional bottom paints start losing their 'punch' from day one, and by the end of the season may be 50% less effective than when new. If you do get a little growth on the bottom with Micron, it is easy to wipe off with a sponge or soft brush. I've used Micron 25 for the past four years, that is, I put Micron on four years ago, and have yet to re-paint. And when the boat came out this fall, I didn't even have to wash the bottom: Some of the other boats in the club had a thick coat of algae and owners spent up to an hour scrubbing with brush and hose.

 

My second choice of paint is International's TBTF, whose biocide is a Tributyltin­fluoride, or any other paint that contains TBTF or TBTO as the biocide. We'll talk about why when I come to the keel. Such as Woolsey's Miracol. Frankly, I'm not all that familiar with paints other than International, which seems to be the best seller around here. However, there are two basic kinds of anti-fouling paint. Those (like Micron) that wear away, more or less like a bar of soap, and those that don't. In theory, with a paint like Micron, you will eventually wear it away until the gelcoat is exposed. Which suits me just fine. Who needs a build-up of years of paint? However, having said that, I also must tell you, these newer co-polymer paints are generally a lot more expensive: I believe Pettit's 'Offshore' is similar to Micron. If you'd like more info on bottom paints, get a copy of 'Practical Sailor's' 1984 Gear Buying Guide. (Neptune, by the way, did very well in their survey in your area.)

 

Enough about the bottom. Now the keel: Iron keels are both a blessing and a curse. A blessing when you hit a rock. The only damage is likely to be a little paint removed. Lead keels, on the other hand, generally require major surgery under similar circumstances. A curse because they rust: The factory here gives each new keel a coat of red oxide as a barrier coat, before applying anti-fouling paint. But I don't know what primer the factory at Arlington used on your boat. Which brings me back to one of my original questions. How much rust? If the keel is more or less rust free, I'd assume the barrier coat on your keel is doing the job, and leave well enough alone. Just sand down those few rusty spots, apply a primer suggested by the paint manufacturer you are going to use, then re-paint the keel. If, on the other hand, your keel shows lots of rust, I'd assume the primer to be ineffective, and start over. Sand the keel down to original metal, doing your best to get rid of the rust. A wire wheel on a drill is probably the best method of attack on stubborn rust spots. Then two or better, three coats of International's Vitaline Aluminum, or Vitar. Then an anti-fouling paint containing TBTF or TBTO. Tin is close to iron in the galvanic scale so there is much less chance of a galvanic action between the keel and the paint. Stay away from any paint with Cuprous oxide. Whether you use a brush or roller is pretty much a matter of personal preference. A roller is faster, but a brush gets into the nooks and crannies easier. Probably a combination of both is a good bet.

 

Now, to answer your last question. Where to mount the depth sounder transducer? Despite the temptation to mount the through. hull as far forward as possible, I would not do so. No matter how forward it is mounted, by the time it shows up on the sounder, it is already too late and you've already hit bottom. The main reason for not mounting the transducer in the forward third of the hull is that any protrusion in that area will have an effect on boat performance. Mount it in the aft third. The middle is no good, the keel gets in the road. Here's a thought. Why not try an 'in hull' mounting. You will lose a little range, but avoid making a hole in the hull. Just smear a great gop of caulking compound (such as Boat-life) on the inside of the hull, close to the center line as possible, in the cockpit locker. Then plunk the transducer into this air bubbles. Let harden and that's all there is to it. I have used through-hull mountings, in-hull water box mountings, and the above method. And I like the latter best. If you do opt for this method, just make sure some clumsy soul doesn't drop your anchor on top of the transducer when you aren't looking.

 

 

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