You should never sheet in hard on the spin (unless you are reaching). It should always be sheeted so it doesn't fall in, even in heavy air, you will notice a huge difference in sheeting out that last inch.
Maybe your main is not sheeted correctly to your spin. Personally I use tell tales a the leech of the sail top 3 battens. I let out the main untill those are flying (this will seem quite far out, but works ok for me (mast will look quite bendy). This will generate more power and lift in the main and might work better for the spi too.
Also talk as skipper to your crew when heading up or bearing away, and crew should inform the skipper how the spin feels.
Finally go your own course. If your spin isn't made to sail high and fast don't do it, because it will not work.

Just sold a new Glaser spin to one of the Blades here, I'll let you know my experience.

Gill

" Now Jody, if you would hurry up and get down here, we could get out and practice all this stuff on days like today!"

Don't tempt him!!!! Can't believe he is breaking up a great team and leaving me here!!

You should come on down too Joanna, plenty of room, plenty of sun, plenty of water for all!

Question for Matt...

Have you ever considered, or been asked to put a short track on the hulls to allow tweeking of the kite sheet leads?

Tim-Will consider it, but HAVE to have jobs first! Plus it is hard to beat working only Tues-Thur.

I rigged up the barber hauler set up several times as we worked to develop the spin for my boat. It would be an easy enough installation to mount a short section of jib track to the hull if you really wanted. I am not sure why you would want anything “mounted” permanent. There is way more than enough going on with lines and such on the boat now. The spin as I try to set it up is set and forget. All the way up and all the way out – then pull from 1 place
A few boats have been supplied with multiple spin block attachment points. I found it does not matter except in the very lightest air – then the crew is low anyway and can pull directly on the clew.

For me the fewer adjustment I make is directly proportional to how fast I sail.

I wasn't thinking of an actively adjusted track. More like a pin stop thing like they originally had on the hobie 18 for the jib. Theory being you could set it on the beach for the conditions and also adjust for different kites without playing with pole height etc.

Gill,

Any concerns about mast breakage when easing your main out a bit? I sailed the N20 like this in once race, previous owner saw the boat and commented that the main wasn't tight enough and your mast was bending all over the place. I took his advice as he is a far better sailor than I, but I felt the eased main was faster. During Tybee I dropped the traveler a lot and eased the main probably more than recommended, but this was typically only done when trying to out climb F18's or impending Jetty's.

I'm surprised at the variety of spinnaker cuts in this fleet, I think the F18's have all tended to a flatter cut at this point. I'm also surprised the issue of where to sheet the spinnaker hasn't come up before in other classes? Based on this information it sounds like buying the same sail as originally supplied with the boat is best to avoid drilling holes but maybe that sail shape isn't fastest.

Jody and Joanna, do you feel faster with the flatter spinnaker when its trimmed properly?

What Gill is saying is just ease the Main enough to get the Tell tales to fly properly, which isn't much. The main will stall if you don't. It will help to drive the boat better.

Most of the masts that do break with the spin up are in the most extreme cases. For one instance, going downwind, stuff the hull, the main comes uncleated(eases out a LOT) and you stuff the hull. Another one is you capsize, and the spreaders aren't centered on the diamonds and then once you sheet hard going upwind the mast breaks. That situation is resolved by putting some epoxy about an inch above and below where the spreaders are connected to the diamonds.

Again, the most extreme cases....


Mike

I forgot to mention,


The difference in the spins is just improvements that the sail makers do each year. It's that way with the mains too.

On a calm day put your spi out and sheet it in all the way. Look at the sheet and the line it forms from the pulley to the clew. Basic measurement is to make sure this line crosses the luff at 90 degrees or so. It is usually better to have the pulley too far back than too far forward as you really don't want to close the gap between the spi and the main by pulling the clew down, so if in doubt, move it back.

When I changed spi from the original Stealth 'R' cut to the GP F16 one I had to change all the geometry of the front triangle: despite being the same size (17.5m2) the new spi is way flatter, with a longer luff and a clew set lower. I had to lengthen the pole by 40 cms and move the sheet pulley forward quite a bit to be able to get a good shape in it.

Is the pole still legal in length?

Yes, the original Stealth 'R' pole was short. The new one is right at the legal length.

Mike,

Indeed you need to ease just a bit. The Falcon spin is cut flatter then the original Blade one meaning it is easier to match your mainsail position to the angle of the wind (you sail higher and faster).

Just watch out if you start to head up with the main eased to make a mark for example. If you have the main eased and leave out the traveler a fair amount the mast becomes very bendy... :-)

Gill

Tornado's play with the sheet point quite bit. We typically attach the blocks to the tramp lacing points along the inner gunwales. I use a quick release Ronstan clip with lanyard on the pin. We move the blocks forward one position in light air when we can't fly the hull. Then back one posiition for moderate. Finally one or more back positions in the wild stuff.

I've always found this makes huge differences in spin power for the conditions.

When I used a new
spinny from the Canadian Olympic team for hte first time on my boat, I found it was very fussy...constantly collapsing even when sheets beyond what I like to have.
Here you can see the collapse:



And how it looked prior to collapse:



Sent these to the Olympic team I bought it from and the reply was "Luff WAY too tight"...despite using our normal "90 degree fist twist" setting. We had to let out 6-10 inches of halyard before the sail became fast and more stable.

We now have it about right and sail much lower and much faster than my local crowd of F18's in all conditions.

Fantastic info Mike, did they tell you how to recognise that the halyard needs to be let off?

Unfortunately no...just that the pics looks way off from being right and our report of the sail collapsing every few moments/killing our race performance. The GranSegal older/more dialed in sail I put on for the second day of the same regatta got us right up challenging for the lead against the best I20 team in SoCal. We were back in 7th or 8th with the new kite the day prior.
since making the luff looser on the new sail, we are find it to be faster than the Gran.

Does this matter?

Jody is using a Goodall spin on a Blade. The Viper (asuming the Goodall sail was made for the Viper) has its spin blocks on the inside edge of the hull. The Blade has the spin blocks mounted on the outside edge of the hull. Does that make any difference? Gotta be 10 to 12 inches differences there.

Have fun in Gulfport!!!

I'm sure it must matter how far inboard/outboard the spin sheet block is placed. On the T it is always at the tramp lacing points or directly to the inner gunwales. But, the T is a 10' wide boat. I believe I20's (8.5' beam) sheet from the outer gunwales.
In general terms, I would think anytime your creating an excessive curve of the clew inboard toward the sheet point, you're loosing performance (too much "belly" in the sail shape).

That would make a huge difference and is probably the source of the issue. All the modern F18s sheet to the inside as well. As kites get flatter I wouldn't be surprised to see people sheeting off the tramp.