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runner 10-08-2008 08:38 PM

Mast length
 
I have an AMF Puffer hull with no mast. Is a 19 foot aluminum mast too much for that small boat? Making a new boom would let me run sails about the size the boat calls for, but I am sure this mast is heavier than the one that was on it from the factory. I can make a lighter one, but using this one would be easier.

Delirious 10-08-2008 09:23 PM

Um. Yeah.

Takes me back. Our scout camp had a Puffer (and a dozen Sunfish). Everyone raced to get to the Puffer first.

The Puffer Pages!

55 sq ft main. With an eight foot boom that's a lift of about 13 feet. One for the deck-socket and maybe another 24" to the gooseneck is 16 feet.

Take off another foot if it's a nine foot boom.

runner 10-08-2008 10:26 PM

Sailrite shows the original main as 14.33 feet by 7.5 feet. The sail being used on the mast was a 15 footer, but on the smaller boat it would be more like 16 x 7.5. The original setup was holding the boom above the slot by the luff rope. 14.33 times 7.5 versus 16 x 7.5 and the heavier mast. The Jib shows as a touch smaller than the one with the mast, but not much. Using the shorter boom we are talking 65 or so on the main and 30+ on the jib. Right at 100 sqare feet on a 12.5 foot boat. The original sails show about the same for the standard main and genoa combination. The main and the Spinnaker would be 150 or so.
How much difference does a few more pounds on the mast make?
Does anyone know what the length of the original mast on these boats was?
The foot is a sit over type with a small hook and bolt. The mast uses a heavy center pin from the side. I can mill a bracket to change it over. I just don't want to set up a boat that falls over for the slightest excuse.

Delirious 10-08-2008 11:41 PM

Quote:

How much difference does a few more pounds on the mast make?
In a small, unballested boat a few pounds on the end of a lever arm of 19 feet is equivalent to about 40 or 50 pounds of crew weight. You'll be that much slower to recover from a puff and all the more likely to broach during one. You'll also be unbalanced to the center of effort as the rig is designed to a certain center-of-effort vs. center-of-lateral-resistance off the centerboard and you've moved it back if you add 18% more mainsail. It may have so much weather helm your rudder won't be able to compensate; and it will certainly add so much drag fighting the main that the added sq. footage won't help much when going upwind or reaching. If you shorten the boom to compensate that will help - giving you a higher aspect rig - but you'll have to be more careful with crew weight to keep her upright.

runner 10-09-2008 01:49 AM

The original is 17' 10". The sail is 14.33 on the luff. The original main that came with that mast was 15 foot. That mast was a replacement for a wooden original on the dinghy I believe. If I decided to, I could cut this one to close to the original mast length I think. I am not sure how far up the slot starts. The specs give 24 inches to the gooseneck position I think.
I just taped the mast I am considering using. It is 19 foot three inches. The fore stay attaches at 14feet 11inches. I could take about 6 inches off the bottom and still keep a stock boom clearance with the gooseneck most of the way down.
If I don't locate a more likely suspect by the time the boat is fully repaired and ready to go, I think I have to give it a try. I did mention that there was gonna be a big fat feller sailing it didn't I??? :)


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