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Spinnaker size

PostPosted: Tue Apr 13, 2010 10:34 pm
by GreenLake
First, I have to admit that a) my DS has no spinnaker, b) I've never sailed on any boat that had/used one.

Given this, it has always intrigued me when looking at pictures of DS under spinnaker, that these sails look relatively small. At least compared to "typical" sailboats.

My question: Is this impression correct? Are these sails smaller than for comparable boats? Are they the maximum that the DS hull can handle? Or is it because of the way the mast is stayed?

Just curious.

PostPosted: Tue Apr 13, 2010 10:54 pm
by algonquin
I agree with you GL. Seems the spinnaker does appear to be a bit on the small side. My first thought is that the DS is so light and not being a keel boat that a larger spinnaker would be a definite danger. I suspect that is also why we don’t see a sweeping Genoa on the DS either. Brad

PostPosted: Wed Apr 14, 2010 9:31 am
by ctenidae
I have a donated spinnaker, but am not rigged for it at the moment. I'm intrigued, and a bit scared, by the prospect of flying it. It does seem smallish, but what do I know?

PostPosted: Wed Apr 14, 2010 8:32 pm
by shawn
The daysailer has a small spinnaker because the fore triangle is small. The rig is such that the main is proportionately larger than the jib compared to other boats. The trend was to go with masthead rigs (large foretriangle) and small mains in contrast to the more traditional larger main with a fractional rig. The jib was just a blade to create a slot. The spinnakers are designed to be flown just above the headstay where there is the most support. hopefully that helps.

Shawn

PostPosted: Thu Apr 15, 2010 3:35 am
by GreenLake
OK. so the design of the rig dictates where the spinnaker is attached and therefore its size. So far I'm with you.

My next question is whether such a relatively small spinnaker is somehow "underpowered" for a boat like a DS.

I found ratings for DS with and without spinnaker somewhere and they were not all that different, if I recall. So the question I have is whether there really is a large obeservable difference in speed or whether it's so moderate, that it only matters during races (where small differences count).

PostPosted: Thu Apr 15, 2010 8:12 am
by shawn
For the boat's intended purpose, a family daysailer, it's a quick little boat...even by todays standards. Compared to the 420 the spinnaker is very similar. There are sport boats now that carry huge headsails and gennakers but I would question how good they are as a family boat. The Daysailer does plane rather easily so the spinnaker does become less of an advantage once the wind picks up (15+ kts) but again that's how it was designed and why it works so well as a family daysailer. When sailing dead downwind in light wind the spinnaker more than doubles the sail area (the little jib is useless) so there is its virtue.

Shawn

PostPosted: Thu Apr 15, 2010 1:34 pm
by GreenLake
Thanks, Shawn. I take it then, that you imply that if I sail a lot in light winds (which I do), I'm missing out on something by not having or using a spinnaker. Even if I'm not racing.

PostPosted: Thu Apr 15, 2010 9:42 pm
by shawn
Absolutely, I love using the spinnaker and use it any chance I get

PostPosted: Thu Apr 15, 2010 10:06 pm
by GreenLake
Shawn, I think you've sold me on trying it.

Final question: can it ever be single handed with spinnaker or is it out of the question?

PostPosted: Thu Apr 15, 2010 11:08 pm
by shawn
I would basically say it's a 2 man operation. At least putting it up and taking it down. Once it's up I can take care of trimiming the sails and the tiller while my wife relaxes but the main thing is someone (or something) has to man the tiller while you raising and dowsing. Of course the boat could be set up to be singlehanded and I'm sure there are those that have.

PostPosted: Fri Jul 06, 2012 1:44 pm
by GreenLake
This is an older thread, but just to update it, let me add some sort of conclusion.

Somebody gave me a used spinnaker from some other dinghy. It's definitely bigger than the standard DS spinnaker, but in our generally light winds that's not been a drawback (I don't race under class rules, so that aspect is not a concern). My rigging is a bit improvised in other ways since I didn't want to commit to hardware or drilling holes until I get more experience. I lashed some blocks to the stern cleats and I have a fairlead on the cuddy top for the halyards. I'm using various existing cleats for now.

I balked at the cost for a spinnaker pole, or even a spinnaker pole kit, and proceeded with making my own pole from 1"ID bamboo. I glued a set of spinnaker pole fittings into each end (with MarineTex epoxy paste) and then covered the pole with one wrap of very light glass tape (that seals the bamboo and keeps it from cracking and perhaps adds a bit additional strength). Not class legal but much cheaper and lighter.

I've also flown the spinnaker single-handed a few times (again, the light winds help).

PostPosted: Fri Jul 06, 2012 11:11 pm
by jdoorly
GL you didn't tell the most important thing about spinnakers- they make you go fast and yell "WEEEEEEEEEEEEEEEEEE!"

But, different spinnakers have different optimal performance characteristics; my UPS is great from 45 degrees to 135 degrees and then dies like a jib until dead down wind when you can wing and wing it. The class spinnaker works great from DDW up to about 70 degrees. But the BIG deal is all those strings to set; topping lift, downhaul, foreguy, afterguy! My UPS just has a sheet, like a jib- easy to single hand. I'm working on a system to make the UPS work from 135 to 180 degrees, but I haven't built it yet- too much good sailing weather...

PostPosted: Mon Jul 09, 2012 8:40 pm
by GreenLake
Jdoorly,

actually, reaching is pretty rare. Some of my favorite excursions end up as upwind/downing trips on most days, although this weekend I might have been better off with a UPS than a spinnaker - academic, until someone gives me a free UPS (:D).

So we did a nice reaching leg under jib followed by a downwind leg under spinnaker.

Just as we were going "WEEEEEE" in the most approved fashion, we passed a buoy and noticed that we had something like 2kn of following current - what a nice way to exceed hull speed (when you have too much crew to even dream of planing).

parachute as a spinnaker

PostPosted: Thu Jul 12, 2012 4:08 pm
by owldraco
I have an old military parachute with a 14' radius. Each gore is 36" wide at the base. I was thinking of maybe cutting out 3 or 4 gores to make a makeshift spinnaker. (obviously not class legal). Any thoughts? I have had it for awhile, thinking of making something out of it like a tent or a teepee.
owldraco
Central Ky

PostPosted: Thu Jul 12, 2012 9:41 pm
by GreenLake
There are some here that would say you'd get more fun out of it that way than as a tent or teepee :D 8)

If you come close to the official measurements, you might not get overpowered too easily. If you have constant light winds and heavy crew, you can add 6"-12" to various measurements and probably still use the standard attachment point above the forestay.

The cloth should be light enough so that it can be handled by a regular sowing machine. I don't know where you'd go to get instructions (on hems, cringles and shaping, but the problem is in principle not different for many small boats, so you might find a usable reference that's not specific to the DS.

For a home made pole, my recommendation is bamboo (if you have a good source, and have epoxy/glass for a thin outer layer). I think I described that above somewhere. The epoxy and glass for mine were minuscule amounts (from "stock" so to speak) and the pole was only $5.00. Try that with aluminum :(

Let us know if you find suitable info.