September 2007 - montgomery_boats - mailman.xmission.com

Re: M_Boats: Re: Cabin heaters
by Larry E Yake 29 Sep '07

29 Sep '07

John, Thanks for this posting. Very timely. I'm hoping to get another month of sailing up here in the northwest, but nights in the 30's and days in the 50's make it pretty chilly. Looking forward to seeing the details on the Sterno heater you're building. By the way, saw some pictures of your old cat boat. BEAUTIFUL! Larry On Fri, 28 Sep 2007 22:03:45 -0500 John R. Butler <theoldcat(a)cox.net> writes: > Perhaps this excerpt from an article I wrote about heating systems > for boats may summarize some of the many contributions on the > subject. My article was published in "Sail" in Sept 1977 and > "Motorboat" in October 1977. > > ÂOne caution that should be common knowledge which always > bears > repeating: never use an unvented combustion-type heater in a closed > > cabin. The fire uses oxygen, the same as people do. People go to > sleep with such a heater on. The heater uses oxygen. The oxygen > level > goes down. The heater canÂt get enough oxygen. The combustion > process > puts out carbon monoxide. The people begin asphyxiating. Their > central nervous system tells them to breathe more deeply. They do. > > They breathe in huge gulps of carbon monoxide. Then they die. The > proper solution to this fatal possibility is a properly vented > system. > ÂMany fuels produce water vapor as a combustion byproduct, > and an > unvented heater aggravates the dampness aboard a boat. On the other > > hand, a properly vented combustion heater dries the air. As air is > > exhausted up the chimney, fresh air is drawn into the cabin. As this > > air is warmed, its relative humidity decreases. This drying effect > is > actually typical of any heater which causes fresh air to enter the > > cabin even when the outside air is damp. > ÂIf cool, damp outside air is warmed up, the water vapor is > > dispersed in a larger volume of air and the air feels drier. Look at > > tables 16 and 17 in Bowditch. If the outside temperature is 50 > degrees and the relative humidity 100 percent (saturation, visible > > mist), warming the air to 74 degrees will drop the relative humidity > > to a comfortable 43 percent. A boat cabin probably wonÂt get that > dry, as the outside air will mix with the humid inside air and > ng and cooking will add moisture to the air, but the > difference will be noticeable and pleasant. Solid fuel stoves will > > make a greater difference because they use more air but they also > use > more fuel, given their chimney loss. However, the lower cost of wood > > or coal makes that greater fuel consumption acceptable. > ÂUnvented heating systems, such as some electric systems, > will cause > an initial drying of the air as the cold damp cabin is warmed, but > > when the temperature stabilizes and breathing and cooking add > moisture, the humidity rises. Then when the temperature is lowered > at > night for sleeping, the cooling air canÂt hold as much moisture and > > the humidity reaches the saturation point. Then water condenses on > > ports, overheads and the inside of the hull. The dripping calls for > > dehumidifying.Â > > John R. Butler > theoldcat(a)cox.net > > > > _______________________________________________ > http://mailman.xmission.com/cgi-bin/mailman/listinfo/montgomery_boats > >

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Re: Cabin heaters
by John R. Butler 29 Sep '07

29 Sep '07

Perhaps this excerpt from an article I wrote about heating systems for boats may summarize some of the many contributions on the subject. My article was published in "Sail" in Sept 1977 and "Motorboat" in October 1977. “One caution that should be common knowledge which always bears repeating: never use an unvented combustion-type heater in a closed cabin. The fire uses oxygen, the same as people do. People go to sleep with such a heater on. The heater uses oxygen. The oxygen level goes down. The heater can’t get enough oxygen. The combustion process puts out carbon monoxide. The people begin asphyxiating. Their central nervous system tells them to breathe more deeply. They do. They breathe in huge gulps of carbon monoxide. Then they die. The proper solution to this fatal possibility is a properly vented system. “Many fuels produce water vapor as a combustion byproduct, and an unvented heater aggravates the dampness aboard a boat. On the other hand, a properly vented combustion heater dries the air. As air is exhausted up the chimney, fresh air is drawn into the cabin. As this air is warmed, its relative humidity decreases. This drying effect is actually typical of any heater which causes fresh air to enter the cabin even when the outside air is damp. “If cool, damp outside air is warmed up, the water vapor is dispersed in a larger volume of air and the air feels drier. Look at tables 16 and 17 in Bowditch. If the outside temperature is 50 degrees and the relative humidity 100 percent (saturation, visible mist), warming the air to 74 degrees will drop the relative humidity to a comfortable 43 percent. A boat cabin probably won’t get that dry, as the outside air will mix with the humid inside air and breathing and cooking will add moisture to the air, but the difference will be noticeable and pleasant. Solid fuel stoves will make a greater difference because they use more air but they also use more fuel, given their chimney loss. However, the lower cost of wood or coal makes that greater fuel consumption acceptable. “Unvented heating systems, such as some electric systems, will cause an initial drying of the air as the cold damp cabin is warmed, but when the temperature stabilizes and breathing and cooking add moisture, the humidity rises. Then when the temperature is lowered at night for sleeping, the cooling air can’t hold as much moisture and the humidity reaches the saturation point. Then water condenses on ports, overheads and the inside of the hull. The dripping calls for dehumidifying.” John R. Butler theoldcat(a)cox.net

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M15 on Craigslist SanFran area
by Nebwest2＠aol.com 28 Sep '07

28 Sep '07

whatever ************************************** See what's new at http://www.aol.com

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M17 Idasailor kickup rudder&mast support?
by Gary M Hyde 28 Sep '07

28 Sep '07

Does anyone have the new Idasailor full kickup rudder for the M17? If so, how do you support the mast during trailering, please? You can see a photo of it at: https://www.idasailor.com/catalog/product_info.php? cPath=45&products_id=466&osCsid=8291e738582bdbd212e710c2708785c9 Regards, --Gary Hyde gmhyde1(a)mac.com 2005 M17 sailboat #637 'Hydeaway 2' We can't change the wind, but we can trim our sails.

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M15 on Craigslist SanFran area
by Nebwest2＠aol.com 28 Sep '07

28 Sep '07

Good thing 'Jo doesn't frequent the list Gary, or you'd be getting me in trouble! You better be on your best behavior when you come up here.....I'm walking that fine line right now....my crew is about to mutiny on me! Don't get me in trouble! lol Sean (soon to be single-hander I fear!) ************************************** See what's new at http://www.aol.com

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Re: M_Boats: M15 on Craigslist SanFran area
by GILASAILR＠aol.com 28 Sep '07

28 Sep '07

In a message dated 9/28/2007 2:48:51 PM US Mountain Standard Time, Nebwest2(a)aol.com writes: http://sfbay.craigslist.org/eby/boa/433279327.html Sean - You are not exactly the right size for a M-15 me thinks. So it is of little chance you will be needing to buy one today - No Value to you. Although - you have owned a 17,23 and this could round out the ballasted Monty fleet - with the rare 17FD needed for the whole gang, Jo wadda ya think? GO Team Geezer Racing.....Old and in the Way Arizona Sailing Squadron ************************************** See what's new at http://www.aol.com

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Re: Cabin heaters
by John R. Butler 27 Sep '07

27 Sep '07

Cabin moisture: YES, any unvented heater will increase the humidity in your cabin, and it quickly goes to 100%, then condensation forms everywhere and it rains on you! Another source of water in your cabin: YOU when you breathe! To keep your cabin warm AND dry, use a vented heater. My first M15, then my Cape Cod Catboat, and soon my current M15 all had vented heaters, so the inside air was always not only warmer, but drier. John R. Butler theoldcat(a)cox.net

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M17 Idasailor kickup rudder&mast support?
by Gary M Hyde 27 Sep '07

27 Sep '07

Does anyone have the new Idasailor full kickup rudder for the M17? If so, how do you support the mast during trailering, please? You can see a photo of it at: https://www.idasailor.com/catalog/product_info.php? cPath=45&products_id=466&osCsid=8291e738582bdbd212e710c2708785c9 Regards, --Gary Hyde gmhyde1(a)mac.com 2005 M17 sailboat #637 'Hydeaway 2' We can't change the wind, but we can trim our sails.

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Heater
by Nebwest2＠aol.com 27 Sep '07

27 Sep '07

Checked out the Wallas heaters online.....that looks like the ticket. Oddly enough they won't list the prices on the web-site. Hmmmm I emailed for prices. I'm guessing that they are going to be pretty substantial. I'll post them here after they reply to my request. ************************************** See what's new at http://www.aol.com

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Re: Pulpits
by John R. Butler 27 Sep '07

27 Sep '07

Capt. Sadler, my bow pulpit is ABSOLUTELY ESSENTIAL to a guy with a long-gone sense of balance like me. I have slide on my butt to get to the foredeck, and need the comfort of a good handhold up there. John R. Butler theoldcat(a)cox.net

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