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 Post subject: Letting out the hot air.
PostPosted: May 21st, 2016, 8:42 am 
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As those of you who own GTC's in the hotter parts of the country know, the lack of roof vents can lead to really uncomfortable conditions in Summer when hanging out inside. After dithering about how to best address the problem for over 5 years, I finally decided to bite the bullet and bought a Maxxair Maxxfan with a rainproof lid, 10 fan speeds and a built-in thermostat.

Deciding where to install it has a lot to do with where cieling wiring is located and which part of the bus needs the most air movement and ventillation. I've decided to install it in the aft cabin and will remove the overhead light to take advantage of the existing conductors - plus, the ability to drive with these vents open in any weather (even if all we get these days is dry!) means that there will be good ventillation without having to have a window open. Creating the opening has kept me virtually sleepless for days worrying about getting the top and inner aperatures square and perfctly aligned, and I went so far as to buy a Rockwell mini circular saw with the ability to plunge-cut to help make the cuts without damaging the wiring.

I intend to take photos.


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PostPosted: May 22nd, 2016, 1:29 pm 
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Mission accomplished! That's the good news. The bad news is that I only was able to take a single cellphone shot of the hole I cut in the roof. The rest of the time I was too busy and covered with glass dust to get any more shots. I can tell you that these machines are very well put together internally as well as on the surface. The roof laminate has an average thickness of 1/4", the closed cell plyurethane foam inslutaion is 1.5" to 2" and the inner liner averages 1/8" to 3/16ths. Looks like an excellent proportion of resin to fiberglass and appears to have been hand laminated mat. There are (I think) 4 steel inner frames located strategically to keep the construct strong.

I used a Rockwell plunge saw with a carbide blade, which worked OK on the roof but was a major PITA when cutting the liner. You can't see the blade, but must rely on a hard to see laser line to keep the cuts true. Bad design. There's a vacuum vleaner attachment point that does a good job of preventing complete disaster on the interior custs, but handling the vacuum hose and the saw - overhead, no less - makes for an interesting time of it.

I fany of you decide to do this very worthwhile project, feel free to ask questions. The fan works like a dream.


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PostPosted: June 8th, 2016, 4:35 pm 
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Location: San Diego, CA
Need pictures or at least measurements where you put it. Even after pictures would be good. It's no fun climbing on the roof of these if you're scared of heights. The round shape is not very comforting. Watch out for low bridges now.

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www.NicksGarage.com == www.HallGTC.com == www.NicksTeardrop.com


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PostPosted: June 13th, 2016, 8:26 am 
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You're quite right about the rounded roof issue. Even though the actual total roof width is about 7', the actual safe zone is only in the 3' range - or that's the way it feels. The rounded roof profile make it way stronger than a flattish roof, regardless of the material, so there's no worry about damaging the structure by wlaking on it.

I used the C/L of the rear overhead light fasteners as the actual center of the roof and went from there to establish the centered (required) 14" square hole location. It's easy to square it up by using the teak door trim as a reference for the corners. The door trim coincides with the steel frame location as well, so there's no chance of accidentally damaging the frame in this area. I located the opening using the aft-most screw hole and slight discoloration of the ceiling liner so that all traces of the light fixture would be covered by the new vent inner trim piece.

I just returned from a weekender in Monterey and the vent worked nicely! I'm very glad that I finally worked up the nerve to make this particular improvement. The other changes I made that really make a difference are the new "See Level" tank and house battery voltage monitor; the VASTLY improved modern AC/DC converter - charger and replacing the door to the head with a soft accordion shower door, which is lighter than the original; allows much easier access to the head and the claustrophobia level is greatly reduced. :-)


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PostPosted: June 13th, 2016, 10:47 am 
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So if you wanted to put the vent forward of the existing light, you could run the wires through the foam to the vent opening? I like having a roof vent but will wait until I actually start using the rig to make that decision. I have a Fantastic Fan on my other camper and it's very nice.

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Nick Taylor - Green & White 1974 Hall GTC.
www.NicksGarage.com == www.HallGTC.com == www.NicksTeardrop.com


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PostPosted: June 13th, 2016, 10:59 am 
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Just looked up those Maxx Fans, pretty cool design. Their old ones were big and clunky. I like the folding rain shield. Did you get the remote control as well? Now you've got me wanting to cut a hole in my roof!

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www.NicksGarage.com == www.HallGTC.com == www.NicksTeardrop.com


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PostPosted: June 15th, 2016, 1:44 pm 
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I suppose that it's "possible" to locate the vent hole somewherre else, but I really did a lot of measuring, poking and prodding before making the move. The way I did it requires no horizontal boring therough the foam and won't compromise the integrity of the top in any way (that I'm aware of!) The fan is really cool. Ha ha ha. I like the aerodynamics of it when closed - and even when open it's not too bad. I decided on the non-remote version because one less electronic widget means one less thing to not work whe you need it.


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PostPosted: June 15th, 2016, 1:45 pm 
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Sorry for the spellink mistage in the prev. post.


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PostPosted: June 19th, 2016, 5:18 pm 
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If I did it, I'd go for the remote so I wouldn't have to get out of bed to change it. In my Brougham the ceiling is so low that when I'm in bed I can reach the fantastic fan without getting up.

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www.NicksGarage.com == www.HallGTC.com == www.NicksTeardrop.com


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PostPosted: June 22nd, 2016, 1:11 pm 
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Not such a bad idea. In our current heat though, the vent simply pulls in more 105 F air from outside!


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