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Munchausen's Replica

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Sat May 03, 2008 5:27 am PostPost subject: Munchausen's Replica
munchausen
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Let me start by saying chances are, I'm not looking for your advice so please don't post in this thread.

That said, I am soliciting the advice of alsetalokin and I'm definitely open to hearing from some of the more helpful members of this board: MADPROF, Yadaraf, Overconfident, and Harvey.

Obviously I have no power to restrict the rest of you from posting but I will thank you for showing restraint. As Yadaraf alluded to recently, too many cooks spoil the broth.

My magnets arrived today and tomorrow it may rain so I should have some time to replicate. Already started playing with the magnets and I broke 1 of my 10 ring magnets. I sure hope that wasn't a magic one!

Al, where should I start?

Now I know some of the other guys are focusing on the spindle issue. Should I wait for them?

I do not have immediate access to any nice plastics but I'm looking into it. Should I start with wood? Does it make any sense to work on a crude replica?
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Sat May 03, 2008 6:05 am PostPost subject:
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I have not posted here for a good while. [been lurking]

munchausen, I suggest you should first carefully study your stator magnets using your magnetic viewing film. Treat each one individually. Label each one. Take good notes regarding any differences between them that you can determine using your magnetic viewing film.

Axle
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Sat May 03, 2008 7:06 am PostPost subject:
Yadaraf
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@munchausen,

Glad to hear you're diving in. Cool

.. Q: I understand you're interested in hearing from Al primarily, but for the record, have you read the log of Al's work for the period of Oct07 thru Jan08?

I ask only because I'm not sure what you've studied thusfar.

.. Log: http://www.ospmm.org/whipmag/pdf/OC_motor_012708.pdf

Note: Dec 5th is when Al received his 834's.

Cheers Smile
Yada..
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Sat May 03, 2008 11:09 am PostPost subject:
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EDIT: removed to preserve munch's thread.
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Last edited by MADPROF on Sat May 03, 2008 10:32 pm; edited 1 time in total
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Sun May 04, 2008 3:16 pm PostPost subject:
alsetalokin
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How did you break the magnet? I haven't broken any of mine {yet.}

Just a reminder to those who might not have a lot of experience with strong NdBFe magnets: Don't let them get away from you!! They can cause serious injury. Especially when they fly together and red-hot chips come spalling off, directly towards your eyes.
Don't try to drill or grind these magnets. Not only will you make a big mess, but they are flammable and can ignite, producing toxic fumes. The unburned dust is toxic too.

I second Yada's suggestion to mark the magnets in some way so that you know which is which.

Where to start? I don't know what your capabilities are, nor what tooling you have available. I doubt that you will be happy with wood, unless you have a lot of experience with that material and some good woodworking tools, like a lathe and a joiner/planer and a router table.
Acrylic plastic (and other kinds) can frequently be obtained from the right scrap piles. Check your local resource lists for plastics supply companies, sign manufacturers, etc. I would bet that if you live near any kind of big city, you can find a scrap pile that will provide your plastics for a pittance.

But seriously, I would suggest that you actually back up a bit. Just what are you trying to build, and why? What is your motivation, what do you expect to find, what will you do if your expectations turn out to be unrealistic?
The first part of scientific exploration (after study and serendipity, of course!) is to be very clear about your hypotheses and the nature of your data.
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Sun May 04, 2008 3:34 pm PostPost subject:
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@Al

I have had one go at the whipmag, but if yours was the cheese mine would have been chalk, worlds apart.

Q. If I replicate yours as close as I can would there be a good chance of seeing the same results as yours? Rolling Eyes

Sorry Munch done it again, but this will help with your enquiry.
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Mon May 05, 2008 4:46 am PostPost subject:
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Yadaraf, I've read most, if not all, but I will review the old stuff.

alsetalokin wrote:
How did you break the magnet? I haven't broken any of mine {yet.}

I let them snap together with a more powerful magnet. Big mistake.

alsetalokin wrote:
I second Yada's suggestion to mark the magnets in some way so that you know which is which.

I doubt the viewing film will be precise enough for small variations, but I will. And what do I mark them with (I remember someone was talking about this).

alsetalokin wrote:
But seriously, I would suggest that you actually back up a bit. Just what are you trying to build, and why? What is your motivation, what do you expect to find, what will you do if your expectations turn out to be unrealistic?

Oh, so the elusive Al has some questions that he wants answers to? Twisted Evil
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Mon May 05, 2008 5:00 pm PostPost subject:
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munchausen wrote:
Yadaraf, I've read most, if not all, but I will review the old stuff.


@munchausen,

I believe one could replicate Al's device if more attention were paid to Al's protocol rather than his specific choice of parts, which is why I think the log is key. Al took some parts, did a lot of tinkering, and finally got his parts to work. Luck was also important, but Al mentions this in his protocol.

Could the device be made from wood? If static electricity plays a role in the Whipmag effect, then the answer is probably "NO" unless you coat the wood. Furthermore, if SE does play a role, it might be necesary to move to Canada where SE is stronger and where the effect was demonstrated. In addtion, SE is seasonal, so the device might run only during the winter.

Cheers Smile
Yada..
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Mon May 05, 2008 11:52 pm PostPost subject:
lostcauses
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"I believe one could replicate Al's device if more attention were paid to Al's protocol rather than his specific choice of parts, which is why I think the log is key. Al took some parts, did a lot of tinkering, and finally got his parts to work. Luck was also important, but Al mentions this in his protocol. '

LOL its such that some understanding of what you are making must be done. To many variables just to do a device and expect it to do what was presented. Way to many details are left out of the specs, as well as an understanding of what is going on.

Them that have built have proven the first part of AGW sync. This is a plus as for the second????

Your just going to grap parts and build, and expect what?
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Tue May 06, 2008 12:52 am PostPost subject:
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lostcauses wrote:
"I believe one could replicate Al's device if more attention were paid to Al's protocol rather than his specific choice of parts, which is why I think the log is key. Al took some parts, did a lot of tinkering, and finally got his parts to work. Luck was also important, but Al mentions this in his protocol. '

LOL its such that some understanding of what you are making must be done. To many variables just to do a device and expect it to do what was presented. Way to many details are left out of the specs, as well as an understanding of what is going on.

Them that have built have proven the first part of AGW sync. This is a plus as for the second????

Your just going to grap parts and build, and expect what?

@lostcauses,

Al has the advantage that he understands practical magnetics very well and can observe important subtleties in magnet behavior that are critical to the tuning of the Whipmag. You and I would dismiss these behaviors as unimportant. At this time, if you wish to build a working Whipmag, then you have to hone your skills in practical magnetics. Perhaps in a year or so there might be a step-by-step procedure with a parts detail, but don't hold your breath.

In the meantime, if you have time then try to enjoy the journey. Cool

Cheers Smile
Yada ..
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Tue May 06, 2008 12:56 am PostPost subject:
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I used "Sharpie" markers, black and silver, to mark my magnets. It wears off after a while. So I redo it.
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Tue May 06, 2008 1:06 am PostPost subject:
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There is a lot that is taken for granted. I worked pretty much full-time on this over the midwinter holidays and built a couple of smaller versions before going on to the 13x8, and a lot of things did come up that others might not have noticed, or might have made different assumptions about.
One example: Most of the development and early testing was done on a wooden table. I noticed that even a small screwdriver. left within 6 inches of the unit, would prevent anything interesting like AGW from happening. Yet the unit worked perfectly well sitting on a metal table for the video--probably because the field distortion was uniform in the latter case, and orthogonal to the behavior of interest.
Another thing: before we started, I never would have thought that one could get away with ferromagnetic bearings in this kind of design. I just tried what I had, and was amazed when they didn't seize up quickly. In fact my bearings seem to work better as they get "worn in". This is probably due to the alternation of polarities experienced by every part except the stator outer races. Would ceramic or plastic/sapphire bearings even have worked at all?
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Tue May 06, 2008 1:42 am PostPost subject:
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alsetalokin wrote:

...
One example: Most of the development and early testing was done on a wooden table. I noticed that even a small screwdriver. left within 6 inches of the unit, would prevent anything interesting like AGW from happening. Yet the unit worked perfectly well sitting on a metal table for the video--probably because the field distortion was uniform in the latter case, and orthogonal to the behavior of interest.

@Al

RE: Metal table

Thanks for sharing.

I'd heard the story of the screwdriver, but it never made sense to me, because the Whipmag was demonstrated on a steel table (much larger than a screwdriver). Now that I understand that the "screwdriver-effect" was observered on a wooden table, I feel oddly reassured. Cool Havery, did you know about the wooden table?

Cheers Smile
Yada ..
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Tue May 06, 2008 2:42 am PostPost subject:
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Most interesting on any near metal as a problem and the table working. Have you used the metal table for testing since?
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Tue May 06, 2008 3:23 pm PostPost subject:
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My prediction is that soon, I will have started more than half the threads on this forum. I guess that is to be expected with this crowd: a bunch of scatter-brained mad scientists who post their crazy thoughts is whatever thread they want to. It's a small irritation, but I live with it. Smile

Yadaraf wrote:
I believe one could replicate Al's device if more attention were paid to Al's protocol rather than his specific choice of parts, which is why I think the log is key. Al took some parts, did a lot of tinkering, and finally got his parts to work.

I agree, and that is one reason I made this thread. OC and Al went back and forth for a long time talking about the designs. I have been a little surprised that no one else is doing the same with Al to make the whipmag.
alsetalokin wrote:
I used "Sharpie" markers, black and silver, to mark my magnets. It wears off after a while. So I redo it.

Sounds good. I looked back at the threads and saw that someone warned against marking the plastic stuff with permanent markers.
alsetalokin wrote:
There is a lot that is taken for granted. I worked pretty much full-time on this . . . I never would have thought that one could get away with ferromagnetic bearings in this kind of design. I just tried what I had . . .

I try to take nothing for granted. That is why Iím hoping to get a lot of insight from you. I think Iíll start with wood since my uncle has a woodworking shop. And I'll move to the plastic stuff when people figure out the spindle problem.

I have some HDD bearings and I may swing by a hobby shop for some stator bearings.

What do you think about that Al?

How long will those stators spin with a finger flip? 3 seconds? 10 seconds?

Please forgive my ignorance, but ferromagnetic just means it will stick to a magnet right? Steel, iron, etc.?

Do you still believe in your triboelectric series theory? Will wood mess that up?

I know that more qualified and more talented people have worked on this project but I figured I might get lucky. Worst-case scenario, Iím out a few bucks but at least Iím learning something.
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Tue May 06, 2008 4:55 pm PostPost subject:
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Ferromagnetic is a material that will magnetize. A curve of such is shown for such material to demagnetize and then flip it in the other magnetic direction. A good material to make permanite magnets has a very large curve.

Using such for the table in which the video was made is most interesting due to it would cause a drag on the device. Just the normal rundown time would be shortened. It would even have and effect due to induced currents in the table due to moving magnetic fields while in motion. It would be an oposing effect to the moving magnets.

It is also a good item for any stray electro magnet field in the area to cause effect on the device.

It would be interesting to know if this would work on a iron plate of a few inches. Then a non ferrous material of some thickness.
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Thu Jun 12, 2008 1:35 pm PostPost subject:
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I found a bunch of MDF scraps that I will use for my first replica. I took out the dremel and cut my first rotor (with little regard for measurments).

Is this a good material to use. It's pretty heavy and seems to be high quality. I spun my rotor on a drill bit and it appears well-balanced.

I'll cut a handful of rotors when I can get access to a drill press or lathe.

I still need to figure out what I will do for bearings for the rotor and stators.
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Thu Jun 12, 2008 4:27 pm PostPost subject:
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munchausen wrote:
I found a bunch of MDF scraps that I will use for my first replica. I took out the dremel and cut my first rotor (with little regard for measurments).

Is this a good material to use. It's pretty heavy and seems to be high quality. I spun my rotor on a drill bit and it appears well-balanced.

I'll cut a handful of rotors when I can get access to a drill press or lathe.

I still need to figure out what I will do for bearings for the rotor and stators.

munch,

IMHO Boca has the best deal on stator bearings -- $5.95 each includes shipping.

R2AZZ: http://www.bocabearings.com/main1.aspx?p=product&id=3153&n=R2A-ZZ

I bought several, and they are all very similar. I think that one bearing might work better than the others, but not by much of a margin. You can build stator assemblies with nylon spacers and washers from Home Depot. Also, because they are cheap, they have a lot of radial play and exhibit the large precession angle, which characterizes Al's stators. I guess it's time for me to make another video or two ... to show how I build the assemblies and measure the angle.

Lastly ... if you're in the market for rotor bearings, I'm sure you can find something at Boca.

Cheers Smile
Yada ...
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Mon Jun 16, 2008 3:29 pm PostPost subject:
munchausen
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Yadaraf wrote:
You can build stator assemblies with nylon spacers and washers from Home Depot. Also, because they are cheap, they have a lot of radial play and exhibit the large precession angle, which characterizes Al's stators. I guess it's time for me to make another video or two ... to show how I build the assemblies and measure the angle.


Please post a video or pics. I would love to see how you made your stators. I had some ideas, but no good ideas.

I would really like to know more about what bearings I should choose.

Are the BOCA bearings made for horizontal use? I know they sell kits for helicopters, but they sell bearings for RC trucks as well and I don't see a difference. I could put some light oil in some ABEC-5 bearings from my inline skates but then I would want to design my replica for vertical use.

A friend of mine showed me some bearings he had for his inline racing skates. He cleaned them between each practice and said they were Swiss. When he held the inner race and spun the outer race with his finger, that bearing would spin forever. I want some bearnings like those.
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Mon Jun 16, 2008 4:30 pm PostPost subject:
Yadaraf
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munchausen wrote:
Yadaraf wrote:
You can build stator assemblies with nylon spacers and washers from Home Depot. Also, because they are cheap, they have a lot of radial play and exhibit the large precession angle, which characterizes Al's stators. I guess it's time for me to make another video or two ... to show how I build the assemblies and measure the angle.


Please post a video or pics. I would love to see how you made your stators. I had some ideas, but no good ideas.

I would really like to know more about what bearings I should choose.

Are the BOCA bearings made for horizontal use? I know they sell kits for helicopters, but they sell bearings for RC trucks as well and I don't see a difference. I could put some light oil in some ABEC-5 bearings from my inline skates but then I would want to design my replica for vertical use.

A friend of mine showed me some bearings he had for his inline racing skates. He cleaned them between each practice and said they were Swiss. When he held the inner race and spun the outer race with his finger, that bearing would spin forever. I want some bearnings like those.

munch,

I'm behind in videos, but below is a pic of the stator parts. You can get the nylon bushing from Home Depot or Lowe's, and it's 0.625" OD and 0.500" ID -- like Al's. Once you have the parts in hand, it will become clear how nicely they fit together.

Note 1: The ID is slightly less than 0.500", so I wrapped a layer of packing tape around the magnet, washers, and bearing before pressing on the outer bushing.

Note 2: I used a pan head screw, and it fits nicely in the washers (no rubbing, no grinding).

Note 2a: Wink The pan head is too large to fit through the 834DIA, so make sure to place the screw in the bearing bore before assembling the holder.

Note 3: Wink Place a small 1/8" piece of shrink tubing on the 4-40 so that it fits snug in the bearing bore. This keeps the entire assembly centered while you screw it down to the base.

Note 4: The R2AZZ Boca bearings seem to work well for $5.95 (including shipping). Harvey uses a different vendor, and his bearings are cheaper I believe. Al's bearings were very cheap -- around $3 if I recall.

Note 5: The 0.500" nylon washers are also from Home Depot, but when stacked together they amount to only 0.066" and not 0.075" as in Al's holder (see holder drawing). They still work, but if you want to add 0.011", I suggest folding a few layers of packing tape together and fabricating a very thin "third" washer. (This is overkilll, unless you're me Twisted Evil )



Cheers Smile
Yada ..
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Mon Jun 16, 2008 6:13 pm PostPost subject:
munchausen
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Thanks for the pic. I'll try to hit Home Depot soon.

Yadaraf wrote:
Note 4: The R2AZZ Boca bearings seem to work well for $5.95 (including shipping). Harvey uses a different vendor, and his bearings are cheaper I believe. Al's bearings were very cheap -- around $3 if I recall.


How long will your stators spin after a finger flick?

Al, how long will yours spin?
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Mon Jun 16, 2008 6:23 pm PostPost subject:
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munchausen wrote:
Thanks for the pic. I'll try to hit Home Depot soon.

Yadaraf wrote:
Note 4: The R2AZZ Boca bearings seem to work well for $5.95 (including shipping). Harvey uses a different vendor, and his bearings are cheaper I believe. Al's bearings were very cheap -- around $3 if I recall.


How long will your stators spin after a finger flick?

Al, how long will yours spin?

Not very long ... they are very light. Perhaps s little more than one second?


Cheers Smile
Yada ..
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Mon Jun 16, 2008 10:53 pm PostPost subject:
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With rotor removed so the stator is free to spin freely, when I give it the thumb-flip technique, it spins for around 5 seconds. This is just an estimate, not an instrumental measurement. But for sure it is waaay longer than 1 second.
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Mon Jun 16, 2008 10:59 pm PostPost subject:
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alsetalokin wrote:
With rotor removed so the stator is free to spin freely, when I give it the thumb-flip technique, it spins for around 5 seconds. This is just an estimate, not an instrumental measurement. But for sure it is waaay longer than 1 second.

Al, munch

Thanks! Believe it or not, as simple as that was, it provided a very good data point. Cool My stators are free, but not nearly that free.

That reminds me ... I have a simple test for precession angle that I need to YouTube.


Cheers:)
Yada ..
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Tue Jun 17, 2008 1:46 am PostPost subject:
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hmmm 1 of the 3 stators I have spins for about 5 secs to 8 sec the other 2 only spin for 2 to 3sec.

The 7 sec one I got out of a harddrive that was busted.

-Nentin
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Tue Jun 17, 2008 2:16 am PostPost subject:
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Hi all,

The 7 sec one I got out of a harddrive that was busted.


Is that the bearing out of the head piviot?
I have one of those thats obviously a double row real nice bearing I'm concidering using on my rotor Question
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it seems a shame, the walrus said, to play them such a trick
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Tue Jun 17, 2008 6:18 am PostPost subject:
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"Thanks! Believe it or not, as simple as that was, it provided a very good data point."

yep it does at that. You should add it to lessons learned thread.
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Tue Jun 17, 2008 6:22 am PostPost subject:
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lostcauses wrote:
"Thanks! Believe it or not, as simple as that was, it provided a very good data point."

yep it does at that. You should add it to lessons learned thread.


ToDo:

Yep .. that and the upcoming fish scale test .. and precession angle test ...

EDIT: ... and the 290 RPM thing ... and the 2x vs 4x thing ...


Cheers Smile
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Tue Jun 17, 2008 8:55 am PostPost subject:
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alsetalokin wrote:
With rotor removed so the stator is free to spin freely, when I give it the thumb-flip technique, it spins for around 5 seconds. This is just an estimate, not an instrumental measurement. But for sure it is waaay longer than 1 second.


Just tested mine...thumb or finger same difference fast as I can flick it -- count one thousand one, one thousand two...stopped. Repeated the test 20 times, never get passed one thousand two. Sad
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Tue Jun 17, 2008 9:07 am PostPost subject:
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@Yadaraf,

Here's an idea:

Remember that 1/4"ID tube I brought down there? My scale lets me set the tare (zero out with weight already on it). So...I'm thinking, set the tube on the scale with two magnets in there in repulsion and a thin dowel (3/16") on top of the magnet. (you could weigh the dowel separately if it mattered). Zero the tare. Now, push down on the dowel until the magnets touch and read the force.

Comments?

I just checked two of my rotor magnets this way. I used a laser pointer between them so I could tell when they touched. After 20 tests on the same magnets I conclude the force is 3 Lbs 5 oz. +/- 1 oz. at closure for my 'N42' magnets.

Obviously a stand could be fabricated such that only the bottom magnet touched the scale and could be zeroed out. Then the other magnet and pushrod could be added and a fine adjustment on the pushrod to guarantee the push force at closure. This would be the most accurate measurement of push force.
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