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Huckster
Newbie

Joined: 28/01/2015
Location: United States
Posts: 4

Posted: 09:13pm 27 Jan 2015

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I am a newbie. I have acquired a nice inverter duty 3-phase 1750 rpm 1 horse motor. It is a Marathon electric Black Maxx. First of all I got it free because it was discarded due to having gear oil from gearbox leak on its windings. Is this salvageable?

If salvageable, what should I do?

Can I just clean with alternator cleaning spray? I have already removed stator and windings are not but a little greasy. Motor was still running and did not burn up or seem damaged in any way, was only replaced so would not have to be replaced later on due to oil. I figured if nothing else could be rewound, larger windings with simple pattern seems logical.

It is a 4 pole unit. Does that mean that I could insert 4 neo mags into rotor or what would be best number and size shape and strength neodymium mags. I was thinking 3 in long bars, not sure on best width and depth. Looks like I could go an inch deep into rotor and be OK but that would be some pricy mags.

This is intended to be used for a wind gen, not grid tied. Wanna charge a small 12v batt bank. Wanna build my own controller and run an inverter. I just want to offset some electric usage.

Any help, advice, or suggestions would be greatly appreciated.

rustyrod

Senior Member

Joined: 08/11/2014
Location: Australia
Posts: 121

Posted: 08:59pm 28 Jan 2015

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I have always washed oil out with petrol followed by shellite.

Suggest, Leave the winding's for now, try the magnets.

Remember "centrifugal force" the bigger the magnets the more they will try to leave the building.

Suggest you try fitting the magnets so they are not exactly opposite one another so you end up with a larger gap on one side this will decrease "cogging" Balancing will be fun.

Please correct me someone, If the rotor in Huckster's motor is about 75mm to 100mm in dia he could fit more narrower magnets, increasing the frequency of the output's AC

( I should google this motor to see what is looks like)

I have been trying to get a car alternator to make some power, any power would do.

I started with the articles from Electronics Australia back in the '70s using a Bosch 40 amp alternator.
I have tried rewiring the stater. This worked for 3 amps excitation I got 2 amps charge.
Perpetual motion in reverse.

I have tried gearing them up.

I have tried fitting magnets inside the rotor. I think my magnets were tooooo strong and swamped the stater.

I will try machining a rotor (sometime) with like "T" slots to hold these magnets which are a little bigger than a sugar cube.
There are 12 poles to this rotor, but I only have 6 magnets.

I have acquired a 12 foot windmill wheel and part of a tower, maybe it will make some grunt.

So good luck and I will lurk here and be interested in how you go.

I personally have found the wind to be very fickle and unkind to me.

But HEY the next really great invention is but an idea and an experiment away.

I wish you a howling gale and some GOOD blades.

Always Thinking

Pete Locke
Senior Member

Joined: 26/06/2013
Location: New Zealand
Posts: 181

Posted: 10:25pm 28 Jan 2015

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Gearbox oil wont worry the windings. It's not conductive (under 500 volts) and it puts a nice anti corrosive coating over the internals. Take the thing apart and stand it upright over night to let the excess drain out, but it will be fine. The only time you need to clean it all out is if it's in a hight head situation. Oil is an insulator when it comes to heat. You can wash the most of it out with 'prepsol' (de greaser used for car painting) but an over night drain is as good as you will need.
Cheers
Pete'.

Huckster
Newbie

Joined: 28/01/2015
Location: United States
Posts: 4

Posted: 10:47pm 28 Jan 2015

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Thanks for the replies. With 4 poles, how many magnets would you suggest? I'll measure and post my rotor and motor diameters tomorrow. Will use metric for you. I didn't realize when I first joined that this was an Aussie site. But all the better. Thanks guys.

Huckster
Newbie

Joined: 28/01/2015
Location: United States
Posts: 4

Posted: 01:16pm 31 Jan 2015

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Here are the measurements of my rotor.

Diameter = 99.25mm. (3.75 in.)
Circumference = 298.45mm. (11.75in.)
Depth to shaft = 38.1mm. (1.5 in.)
Width of rotor = 85.725mm. (3.325 in.)

Shaft diameter = 9.5mm (3/4 in.)

I have done more research and am now looking into inserting 3/4 inch cylindrical neos instead of the rectangular blocks I was considering. 3/4 in is the diameter of US pennies. Putting a penny or two under mags should shield the flux. Also looking into placing copper or aluminum around mags to do same, as I don't have the means to make a new rotor. Shouldn't this focus and separate each magnet's flux? Or would I be just fine to just epoxy them in without shielding.

I noticed people are putting rows of mags offset at an angle which makes sense for smoother rotation and I assume flatter waves of current as well. Sorry my vernacular is primary, I am new to this. Also have looked at several magnet sites, wondering if someone would clue me in on one that is more reasonably priced.

Huckster

Huckster
Newbie

Joined: 28/01/2015
Location: United States
Posts: 4

Posted: 02:47pm 03 Feb 2015

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I found some excellent info by zubbly to help me out three part series on induction conversion. God rest his soul. Has past on since his writing. Extremely helpful and easy to follow. Just do a search zubbly ac induction conversion.

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