thanks for your time. I was wondering if you would know about how much a power inverter would cost. I would go with the DC fan idea but I don't have one of those laying around and i was trying to use things that I already had just laying around. I also dont have any DC motors big enough to run the fan blades attached to the ac motor. Any ideas, options, or information you could offer me would be greatly appreciated. thanks again

A good google search under shopping would land you around 1,773 hits for dc-ac inverter with price range from $12 -$600. You haven't really given much detail as the size/ power requirements, but that would be a good place to start looking.

Take care to use an inverter with sign wave output. Using a modified wave inverter (and to a greater extent a square wave inverter) may overheat your motor. Best use a DC motor as you will have less loses in voltage conversions.

About 4x as much as a DC motor...

There are "CoolBreeze" fans and evaporative coolers listed online. It doesn't appear to be an exclusive trade name, so "CoolBreeze" doesn't describe your appliance well enough for a specific recommendation.

If this is a table fan intended for comfort cooling, something built to run on DC will satisfy your requirements better than an inverter. An inverter large enough and clean enough to run your AC fan without overheating the motor will probably cost more than a DC fan designed for use in a recreational vehicle.

You will find several here.

http://www.google.com/search?hl=en&q=DC+fan+for+RV&btnG=Google+Search

Good luck

Go to a camping and outdoors (or Trucker supplies) shop and (assuming your DC is from a 12 or 24 volt battery), buy a fan for camping for that voltage.....or two as they are dead cheap!!

Why avoid head banging? Wear a helmet...

I agree with master-of-none. Brushless DC fans are cheap, easy to mount, and are readily available in a variety of voltages and flow rates. Here is some additional advice:

If this is a battery application, you do not want to waste stored energy as driving a vac fan motor from an inverter would not be as power efficient as using a brushless DC fan.

If the vac fan motor is not inverter rated, an L-C filter will be required to remove the voltage spikes, found on the output of most PWM inverters, that could punch through the insulation of the motor windings.

Good luck.

well here is what I was tryin to do... I'm in the process of makeing a hover craft that I can operate by remote control. The CoolBreeze fan I was refering to is a small bed side fan that you plug into a wall outlet. It sounds complicated to stick with this idea and seems that it would cost more to invert it to DC than if i was to just invest in a small DC motor. So with that being said would any of yal have any advice on what size DC motor I should invest in? The base of the hover craft is 3/4th inch thick and 15" wide and 20" long (plywood). I will need something with enough power to provid lift and thrust. Once I have this accomplished I will prolly need all the advice and info anyone could give me on how to make it remote controlable. I dont know much about servos and things of that nature. Thanks again for everybodies time

Nate

Firstly, if you invest in a model making magazine or two, unless they have changed radically since my days, there will be plenty of finished designs for hovercraft to look at.

Secondly, the amount of power needed is a fairly complex sum of the final weight of the craft, the width of the skirt area and the ride height required.

You also need to balance the weight correctly with the force of the air pressure, it is no good having one end really heavy as this end will probably scrape along the ground, while the other end rides too high.....!

You need a low weight, combined with a stiff and strong construction and plenty of power, so I seriously doubt if batteries and DC motors are the way to go, you probably need high power IC engines at the very least.

Mythbusters had some attempts in this area....

Checkout YouTube.com and look/search for "Hovercraft". I found this (and many , many others):-

Simple Hovercraft