Ballast for an Irwin 24 (Purists Avert Your Eyes?)

Hey, smart people are on this forum!

We've got an old Irwin 24 we keep on the gulf coast of FL. Of course we live in Vermont, but that's another story. We keep the old girl together on a shoestring and have a lot of fun a couple times a year on the cheap.

The sails that came with her were hideous. Last year I got a new headsail for cheap, that comes very close to matching the original design. It improved weather-helm, but we've still got plenty.

This last trip the main tore, and I am having a local sail maker recut a used main to come as close as we can to the what was originally intended. The main was old and tired, and poorly shaped.

My question has to do with a boat's lines and ballast.

I know a lot of boats as they age get heavier. I don't think ours did. Equipment has been removed. The old Stuart Turner engine, shaft, prop, and other hardware is gone. I have no idea what the design water line is, or how to reconstruct it. The boat 'appears' to be floating high, but 40 years later, I have no idea where it's current line came from.

The boat was not designed as a cruiser, and as I've stated the sails were in bad shape and we're taking care of that. But the boat is very 'busy' and very fatiguing on the helm. Look away for a moment and you're pointed somewhere else.

These old boats were designed to the old MORC specs. It's 24 feet long, but only 18 and a half on the water line if I have that right. If we're floating high, that's not a lot of length in the water.

We're not racers, hell we're not really good sailors either, would we do much harm by ballasting the boat? Where and by how much?

We're going down to FL in another two week's time. I'll be happy to file a report. Crude yes, but at least this won't be a virtual experiment.

Steve

 

The I-24 was a spirited little pony in its' day. My experience ( a long time ago ) was that they were fairly sensitive to helm but not overly much. Scruffy sails are sometimes a problem because they can't seem to make up their minds how they want to be sheeted, outhauled, downhauled, vanged, and whatever.

If the boat is a little bit light, that should not be a problem. Before you add ballast, experiment with fore and aft weight placement of crew. A boat as small as this is sensitive to trim. Having removed the engine, you may have upset the balance somewhat. Adding ballast will more than likely cause the boat to be slower. You won't be able to tell much about any of this unless your sails are in pretty good condition. If you discover that ballast is needed, you might consider a large ice chest loaded with the beverage of your choice. Move it around until you find the right place for it.
Keep the faith these are/were good little boats.

 

We've carried quite a bit of beer, but I haven't noticed any improvement in the handling. Although as the beer's weight is transferred from the bilge to the crew, the the boat's vague handling somehow becomes less objectionable. Also if I send the crew member too far forward, this may interfere with the transfer of the beer.

Seriously though, the engine and components were removed before we purchased the boat. We've got to be at least a couple hundred pounds lighter. Tanks and all are gone......

Steve

 

You don't look at that photo and think "gosh that boat is floating high". If you're carrying the outboard as well, and maybe the odd bits of junk that seem to migrate on board every boat, normal age related increase instructure weight plus an esky or two, I doubt you're carrying significantly less weight than a keen crew who were racing a brand new boat with everything left on shore that could be.

 

I can't give a quantitative answer, but to me the painted waterline looks to be high on the bilge. Maybe the boat is floating close to its intended waterline, but a previous owner had a little too much paint left in the can.

 

So on a boat (any boat) where the designer's data has long since been lost, how would one best determine what's optimum?

But using this little boat and it's shape as an example, what are the penalties and advantages to different waterlines? Academically I'd like to understand this better. I can theorize at the extremes, but I'm not a designer.

Steve