Author Topic: Ametek motor magnets (Read 2233 times)

RayW · « **on:** July 31, 2006, 02:27:13 PM »

(blank)

DanB · « **Reply #1 on:** July 31, 2006, 08:51:10 AM »

The result... The current will still be limited by the resistance (so it wont be good for any more power overall) but it will reach full power output at a lower rpm. In most cases ametek motors are suitable for small 4' or so blades and putting neos in there will slow it down too much and probably stall the blade.

Slingshot · « **Reply #2 on:** July 31, 2006, 09:20:50 AM »

While the resistance would stay the same, the voltage should increase with the magnet strength. At the same RPM you would have more voltage capability and equal current, so more power. And you'd need a bigger rotor to drive it.

ghurd · « **Reply #3 on:** July 31, 2006, 09:32:45 AM »

I changed to neos in some other brush motors.

Everything got worse. They weren't very good to start with.

I expect it was because of the new magnets. They did not fit as well, so there were less square inches and less volume of magnet, and the airgap was larger.

G-

TomW · « **Reply #4 on:** July 31, 2006, 09:39:40 AM »

My conclusions are:

The Ameteks seem to run at or near magnetic saturation in the laminates to start so adding stronger magnets has little [no] effect on output but did have more drag getting started.

The pundits may tell you it works, but many of them do not "do" just read I guess.

It is a waste of time and magnets.And that is data from real world testing.

Check my diaries back maybe 2 years. Info was posted on the actual differences.

Several of us tried it but, as far as I can tell, I am the only one still active today.

Cheers.

TomW

TomW · « **Reply #5 on:** July 31, 2006, 09:42:32 AM »

BTW, the venerable old #29 [now discontinued] was an exact replacement size for this. Too bad it didn't work..

T

Slingshot · « **Reply #6 on:** July 31, 2006, 12:43:20 PM »

*********

The Ameteks seem to run at or near magnetic saturation in the laminates to start so adding stronger magnets has little [no] effect on output but did have more drag getting started.

The pundits may tell you it works, but many of them do not "do" just read I guess.

It is a waste of time and magnets.And that is data from real world testing.

***********

Tom,

Since you seemed to be aiming this at me, I'll ask that you consider the post I replied to. Dan believed that winding resistance would prevent output power increase, which is incorrect assuming you allow voltage to rise, and this prompted my (theoretical) response.

How did you deduce the point of magnetic saturation in your core? Was it inferred from the a voltage waveform? If there was only anecdotal evidence based on "no improvement", your proposed cause is also speculation unless your neos were a perfect mechanical replica of the removed ceramics, and identically located/mounted.

TomW · « **Reply #7 on:** July 31, 2006, 03:32:18 PM »

Pundit;

Well, this had no "aim" to it it was a weapon of mass destruction.

I am not going to argue it with anyone.

Fact:

The replacements were so close as to be identical, I did not weigh them, magnetize my micrometer with them nor did I measure the Tesla.

I SAID:

The Ameteks seem to run at or near magnetic saturation.

What definition of "seem" do you not understand?

The measurements were A:B with neo and stock.

I am not looking it up, I know the outcome.

RPM, voltage and current data were gathered with the same instruments and loads / devices.

So, carry on and share Your test results..

Oh, you do not have any?

Then trust mine, I have no reason to misrepresent what I did. It was documented long before this thread started.

This is where I should tell you to kiss my ### but I will not.

I did this long before you even knew the site existed so back off me.

Not sure why I waste time in here just too many jerks and know it alls lately.

T

RogerAS · « **Reply #8 on:** July 31, 2006, 03:43:42 PM »

TomW,

I'll bet the brushes didn't or wouldn't last as long either.

Wishin' I knew somethin' 'cept how blessed hot it is here in Arkansas! ;-\

Hang in there Tom.

RogerAS

Ungrounded Lightning Rod · « **Reply #9 on:** July 31, 2006, 03:54:39 PM »

Please do stick around - if only to keep me honest.

I post my best understanding, and welcome it when someone more in-the-know corrects me. (That's how I learn and correct my errors - especially now, when I'm busy landscaping rather than building mills, and thus have no first-hand data.)

David HK · « **Reply #10 on:** July 31, 2006, 04:25:48 PM »

Having read the foregoing it is quite easy for the innocent reader to observe that they are valued judgements. In the field of engineering, and any discipline in particular, it is by no means uncommon to read diverging views.

The thrust of this article, and the answers in particular, enable the questioner to realise that the Ametek motor is difficult to play around with. In a nutshell, a change of magnets may not be benficial, but he does have the caveats and is free to decide what to do.

David HK

RogerAS · « **Reply #11 on:** July 31, 2006, 07:24:14 PM »

David,

TomW has been put through the wringer lately, and some of it by yours truly. I can be an ass of the highest order, ask around.

Yes technical issues can create many various points of view. Yes folks are free to do as they wish and try whatever they like. As a person previously deeply involved in a serious scientific career I know this better than some. If one cannot defend their data the issue is more open to various interpretations. However when evidence is supported by the testing of others the data becomes less disputable, and the more testing with similar outcomes the less so.

It seems in this instance the responder took an approach of making, or taking, it personal. This is also a freedom, but come with consequences. If TomW's previous work with this particular idea showed it wasn't productive it would seem respectful to at least acknowledge that. If one then wanted to retest the data under their own conditions and criteria I say that's fine and understandable. I say that's a good thing, as the cumulative gathering of information is always productive. There's always the possibility of conflicting results, however remote.

One of the main reasons we all visit this site is to share data and ideas. Crazy ideas to me might be sound thinking to another, but repeatable results are hard to dispute no matter ones personal feelings.

Having said all that I still believe small stepper motors are a viable source of power if one is willing to build enough of them. :-)

Sorry if this message seems a broken line of thought. I just had to go kill a very thick bodied 4.5 foot long timber rattler right up by where the wife parks. It had 12 rattles and a button. My FS92 took it's head right off! Ah the joys of living in the deep woods, NOT!

RogerAS

zubbly · « **Reply #12 on:** July 31, 2006, 07:37:13 PM »

RayW,

i rewound one of the ametek 30 volt armatures. going from memory, the copper wire size in the armatures was a #28, or a #29.

it is surprising they carry the amperage they do produce without giving up quickly.

my opinion, not worth changing mags in them to burn them up quicker.

zubbly

vawtman · « **Reply #13 on:** July 31, 2006, 07:41:29 PM »

Tom how many poles do these have not familiar with them.Thanks

RayW · « **Reply #14 on:** August 01, 2006, 07:14:29 AM »

I would like to thank all who replied to my post about changing the mags in an ametek motor.

Based on the replies it appears that I would get little or no benefit by changing the mags to neos.

Thanks; RayW

DanB · « **Reply #15 on:** August 01, 2006, 08:09:28 AM »

Yes, you could get more power if you increase the voltage of the battery bank - I should think youd stick with about the same size blade though (youd have to test things). But if you stick with teh same battery voltage than the rise in voltage will mostly serve to heat up the motor. A slightly larger blade would help it produce more power in low winds but in higher winds I expect it would get pretty hot.

Slingshot · « **Reply #16 on:** August 01, 2006, 08:38:31 AM »

I was at first surprised by this tirade of defensive name-calling, but after reading through your past few weeks of postings I see it is well in character. My posting was well-intentioned, but I guess some folks have thin egos and need the last word.

TomW · « **Reply #17 on:** August 01, 2006, 09:41:53 AM »

vawtman;

Not sure on # of poles but they have 2 curved mags in them. Some have dual brush sets at 90 degrees too but those are the 40 volt ones I think.

It has been a good long while since I messed with them and my intent was to document some info on the TDM because I saw a lot of advice to use them but no info on what you could expect. I had a lot more energy and patience 4 years ago when this was a more sedate place before the know it all from books types showed up to muddy the waters. There were a lot of folks way back then that did lots of odd things trying to find that easy wind machine.

I think that it has become apparent that the dual rotor style built by our hosts is probably the most bang for the buck but folks still should try things on their own if they can afford the time and resources. Many cannot and they should follow the success stories rather than reinvent the wheel.

I apologize if my attitude offends the thin skinned but I refuse to have my integrity assaulted without responding. We get the same thing on IRC occasionally. People who never try to help or provide useful data but just hang around waiting to snipe the guy who is trying to help if he makes a mistake. Lead, follow or get the hell out of the way.

Cheers.

TomW

vawtman · « **Reply #18 on:** August 01, 2006, 04:49:23 PM »

Im still not convinced that conversions cant compete in the bang for the buck Tom.

I noticed Zubblys blades seem to have a slightly wider chord than others and that helps him break the initial cog i think.

Had the 5hp 4pl flying for a couple months and noticed if the conversion was engaged when the blades were up to speed the turbine played with it where other devices failed.They werent much though, drill motors.

Yes conversions have more loses.Trust me i know them all now.Ill have only around 120 bucks in Sparky when done wire,mags,insulation ect.

I guess well see what the bang for buck ratio is.

Testing 123.

Sorry about your confrontations.This is supposed to be all in fun i thought.

Carry on.

So those Ameteks are like little treadmill motors?Can the bearings handle tubines?

dinges · « **Reply #19 on:** August 01, 2006, 05:39:19 PM »

"I noticed Zubblys blades seem to have a slightly wider chord than others and that helps him break the initial cog i think."

If you skew the magnets (or stator) correctly, there shouldn't be any cogg. Or just a little.

Hence, a motor conversion should start up just as easily as an axial flux genny. However, there seem to be some iron losses, which an axial flux genny doesn't have. I have no idea how much extra loss to expect from this.

What I do like about motorconversions (even if they should give less power output than axial flux gennies) is the solid house, bearings and (usual) waterproofness. Very solidly built, unlike many axial flux gennies.

Again, cogg should not be an issue, if you skew properly.

vawtman · « **Reply #20 on:** August 01, 2006, 06:03:00 PM »

Peter youll see what i mean when you test.That just a little really hampers startup.

No matter how perfect you skew itll still be lumpy I beleive its called slot ripple.

If you could get a magnetized conversion to spin has easily has it was you would be a millionaire now.

Carry on

Norm · « **Reply #21 on:** August 01, 2006, 06:44:29 PM »

I'd like to hear...."Norm I got this here

Amtek and it really isn't working out....I live

a couple of states over...on my way to the

gambling casinos at Niagara Falls how about if

I just drop it off at your place?"

Kiddin' ...but you can take me serious if

you want.....

Havin' a great time in

Conneaut....

Heat index 100 but I suppose its the frame

of mind....or maybe I'm just plain crazy

and no...I haven't touched a drop since

last week....

( :>) Norm.

wdyasq · « **Reply #22 on:** August 01, 2006, 06:55:15 PM »

I've had a chance to turn one of Zubbly's early conversions by hand. I had no special tool to measure the 'slot ripple'. I could not feel it as gentle as I could turn it and I was trying to feel the 'cogging'.

I also have hand turned JacquesM's 5kW hand built turbine with outside magents and skewed laminates. It had no perceptable 'cogging'.

I am working on a project now I believe will be free of, as you call it, 'slot ripple'. I don't think zubbly or myself has a bank account where we could pull a number followed by 6 zeros after it and not get thrown in jail.

We are going to 'carry on.' We will carry on with know solutions and small improvements each time. The wheel will still be round when we finish.

Ron

vawtman · « **Reply #23 on:** August 01, 2006, 07:28:07 PM »

Hello Ron

You mention that you could spin them without noticing any forms of cogging.Slot ripple is a form of cogging(thanks Flux)

In your third sentence you mention your working on a unit free of ripple so in other words your admitting its there and is.

Im with you and Zubbly not against has you can tell.

Whats your plan of attack?

.

. Carry on and i love your last sentence thats what this is all about.

TomW · « **Reply #24 on:** August 01, 2006, 08:12:37 PM »

Norm;

Stop on over into IRC [see my signature] and give me your address, I will send you one i used awhile to play with. No charge, just to see it get played with rather than clog up my storage.

Cheers.

TomW

wdyasq · « **Reply #25 on:** August 01, 2006, 08:12:45 PM »

" In your third sentence you mention your working on a unit free of ripple so in other words your admitting its there and is."

Is this the statement?:

"I am working on a project now I believe will be free of, as you call it, 'slot ripple'. I don't think zubbly or myself has a bank account where we could pull a number followed by 6 zeros after it and not get thrown in jail."

As I am not finished, I don't know what I am going to have. Proper design and precautions, along with known techniques, are being used. So - where am I admitting to anything? Or, are you reading what you want into it?

My plan of attack is to aviod whatever you are doing that hasn't eliminated the slot ripple or cogging and at the same time avoid your problems. When I get it fully assembled I will be able to report back.

Ron

Norm · « **Reply #26 on:** August 01, 2006, 10:19:56 PM »

Tom...I click on IRC and it takes me to

irc://portslave.oneota.net/otherpower and says

page cannot be displayed ...I've switched computers....used to be able to before that...

remember we talked about our ages...I think that

was the last time...

You can E-Mail me and I'll give you my mailing

address and stuff....thanks Tom. I appreciate it.

( :>) Norm.

kurt · « **Reply #27 on:** August 02, 2006, 11:14:20 AM »

norm try these instructions http://oneota.net/~teejaydubya/IRC/chatpage.html

vawtman · « **Reply #28 on:** August 03, 2006, 05:00:04 PM »

Hello Ron

"Proper design and precautions,along with known techniques"

Any chance you could elaborate on that a bit?

Were all in this together arent we?

I dont mind being the guiny pig if thats what it takes.

Make a posting of your thoughts and lets work together to solve problems.

Its all a fun hobby to me.

Carry on

wdyasq · « **Reply #29 on:** August 03, 2006, 06:41:46 PM »

Sure, I'm going to elaborate on it, when I get it to the point of testing.

"Any chance you could elaborate on that a bit?

Were all in this together arent we?

I dont mind being the guiny pig if thats what it takes.

Make a posting of your thoughts and lets work together to solve problems."

I have no plans on releasing information unless I know it is correct. I doubt those who will not read and will do research can help much. Everything I am doing has been covered with the exception of some adaptations I am doing where I will be able to use tapered bearings.

Each time someone with knowledge and skills does make a comment it is assaulted. Even my signature line gets remarked about. Why should one try to explain something to one who cannot even understand a signature line?

Dinges stated a fact, you called him a liar. I stated facts. You said I was wrong. I have no more to comment on cogging or slot ripple until I actually build and test a machine with laminates

Those of us who do quote facts catch flack while the "Museum of Unworkable Devices" research staff encourages the ignorant to waste their money. As a group you have insulted a previous editor, called the most knowledgable posters liars and insist on building crap. Then you wonder why some of us are a bit short.

Ron

vawtman · « **Reply #30 on:** August 03, 2006, 07:42:55 PM »

What would tapered bearings help.Just wondering?

I called Peter a liar?

Not my personality.Just stating facts I LEARNED.

You always act like you know everything with nothing to show for it.

COME ON

I know you were probably itching for a reply to further the arguement.

I should know better by know.

Why the attitude Ron.Its not cool.

nothing to lose · « **Reply #31 on:** August 08, 2006, 08:16:53 PM »

I have # 29's.

Thanks I'll have to remember they should fit in case I find a dead Ametek sometime to rebuild.

News:

Author Topic: Ametek motor magnets (Read 2233 times)