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Graphics of magnetic fields, A5rod, A5rod w/ baseplate

10/31/2002 1:37 PM
Graphics of magnetic fields, A5rod, A5rod w/ baseplate
FEMM 3.2 generated  

10/31/2002 2:29 PM
A5rod beveled top
I was rather surprised to see a minor bevel make such a difference....
10/31/2002 2:44 PM
Re: Graphics of magnetic fields, A5rod, A5rod w/ baseplate
Great and very useful too ....... could you do the same excercise again but this time take the metal baseplate about a third of the way up the magnet, imagine it was a u shape and partially went up the outside of the coil.  
10/31/2002 3:00 PM
A5rod in U bracket
Here ya go Andy
10/31/2002 4:15 PM
A5rod w/ wide U bracket

Here's one where the bracket goes on the outside of the coil, I think this is what you originally wanted. I also did a version of this with copper filling the void between the magnet and bracket to simulate the coil windings. It made no appreciable difference to the magnetic field in this design. I may have not set adequate boundaries for the copper though...
11/1/2002 8:21 AM

Many thanks, its great when someone can confirm experience......  
I make a stacked P90 and use a compound steel plate which goes about half way up the outside of the bottom coil, and your schematic shows the field (mag) does exactly what I've always thought.  
Any chance of giving us a link to this super useful freeware.  
11/1/2002 9:06 AM
mike landry
i just did a search on google for FEMM

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