TD replications

[Floor]

I put a set / array of 5 magnets on the test bench yesterday. I will try to give a
good written description rather than doing a drawing at this time.

The assembly..

Each magnet is  1 7/8 inches  long by 7/8 of an inch wide.
A magnetic pole is on this broad face.
Each magnet is 3/8 of an inch thick through from pole to pole.....

With the north poles of each magnet facing up, the five magnets
were clamped to a flat surface, edge to edge.

This formed a flat, rectangular single magnetic pole, magnet surface which
measured 4 and 3/8 inches by 1 and 7/8 inches.

I used this surface to see if an out put magnet would travel the entire
length due to "luc's force".  It does.  Although the luc's force is greatest
near the ends, there is  NO DEAD SPOT near the center of length of the travel.

This modified user gotoluc configuration can have a very long output magnet travel length.

THERE IS NO LIMIT TO THE OUTPUT, except for the length of this magnet array
which is underneath the output magnet.

    floor

[Floor]

Now...

What seems to be to good to be true just might be.
          And
I cannot say that absolutely, that at 8 inches of output magnet travel length,
rather than at 4 and 3/8 inches of length, there will be no lull in force
when near the center of travel.  I only tried the 4 3/8 inches of travel.
          But
I can say that at 4 3/8 inches of output magnet travel, it does appear to me
as though there is no limit to the potential travel distance in this configuration.
            If
as in the previous drawings (given again below), a single magnet of 8 inches
length were used instead of those 5 magnets (like poles all facing up),  I think
there would be (in fact I know there would be), a lull near to the center of the
output magnet's travel.
         Also
In this last test, I used the output magnet in a 90 degrees of rotation orientation.
That is to say, instead of the 1 and 7/8 inches long edge of the output magnet
riding over the array, one of the ends (7/8 inch length) was oriented over the array.

This was because,  a strip of wood was used to keep the array magnets from popping
straight up and out from the wooden frame work (clamped to the bench top) surrounding them.
This additional wooden member across the surface of the 5 magnets, reduced the width
available for sliding the output magnet along.

One more thing.  If the output travel has a length limitation.  this design is still O.U..

            floor

[Floor]

Some of the neodymium magnets have an extreme coercivity,
or resistance to demagnetization.

I have heard that two neodymium magnets clamped together in
repulsion will lose only a small percentage of their strength even
after ten years. 

But I don't know if this is really true or not.

If someone knows of a reliable information source as to this point
can you please post a link.

floor

[Floor]

Here is what K and J magnetics had to say about it...

    Will my neodymium magnets lose strength over time?

    Very little. Neodymium magnets are the strongest and most permanent magnets known to man. If they are not overheated or physically damaged, neodymium magnets will lose less than 1% of their strength over 10 years - not enough for you to notice unless you have very sensitive measuring equipment. They won't even lose their strength if they are held in repelling or attracting positions with other magnets over long periods of time.

There are some exceptions (like if the magnets are heated up too much or if the magnets are very thin in the magnetization direction relative to the other dimensions), but in general we've found this to be a good assumption.

[Floor]

Now then,  :
Question
"so why don't you just hook the ends of the track to each other ?"

Answer,  / question
Which design (A) or (B) ?
       
Answer
Design (A)

Question
"so why don't you just hook the ends of the track to each other ?"

Answer
Because the magnet gets stuck at either end...
           At one end it must be pushed on.
           At the other end it must be pulled off.
                           Unless
The out put magnet's travel is arrested just short of either end of the track.

In which case, It can then be easily removed from the track, along a different direction.

Question
And if you hooked the track end to end ?.

Answer / question
In which case below ?

1.  The field gradient could be dominated by a single polarity and constant / equal
in magnitude of force, around the interior of that hole / in line with the
length of the track.
   or
2. There could be a bulge in the field at one or more points along that interior.

Which case (1) or (2) ?

Answer
case (2).
... ... ... ... ... ... ... ... ...
Now we are looking at case (2).

Observation
If there is ONE bulge in the field, we are looking at design (A).
                otherwise
If there are TWO or more bulges in the field, we are looking at design (B).

In either design, (A) or (B), I don't know what happens if we hook the ends together.
I have not tried it !   Maybe, with a large enough circle / track diameter, design (B)
would keep going ?
    But that doesn't matter
                   because
                          both are O.U. without connecting the ends like that.
   
When the ends ARE NOT connected like that...
one can  in a manner "connect them" via a  kinetic energy transfer
          (it's also, partly a magnetic transfer).
One can allow specific magnetic force balancing to occur (because physical
relocations are allowed to occur).
    and like I said...
                        I DO KNOW, what occurs upon a straight track....
                                in either design (A) or (B).
Do you ?
              Also
I don't want to run around in circles.
                  smile
I want cyclical work from magnets.
   floor