Electromagnetics info source
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- blacknwhite
- Posts: 483
- Joined: Thu Apr 24, 2008 2:57 am
- Location: US
Electromagnetics info source
[EDIT] SEE SECOND POST
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Can anyone reccomend, what are some of the simplest-to-understand books on PRACTICAL electromagnetics, written more for "electronic hobbyists" who can design and build simple audio circuitry, NOT for electronics engineers?
Ideally, I'd love to find something called "101 voice coil experiments you can weld in your workshop".
Something that a person with a welder, some scrap metal, and a supplier of different gauges of winding coil, could just "experiment" with, making different sizes & shapes of driver and feedback coils, armatures, magnets, and casings.
Thanks,
- Bob
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Can anyone reccomend, what are some of the simplest-to-understand books on PRACTICAL electromagnetics, written more for "electronic hobbyists" who can design and build simple audio circuitry, NOT for electronics engineers?
Ideally, I'd love to find something called "101 voice coil experiments you can weld in your workshop".
Something that a person with a welder, some scrap metal, and a supplier of different gauges of winding coil, could just "experiment" with, making different sizes & shapes of driver and feedback coils, armatures, magnets, and casings.
Thanks,
- Bob
Last edited by blacknwhite on Mon Dec 01, 2008 10:12 pm, edited 2 times in total.
- blacknwhite
- Posts: 483
- Joined: Thu Apr 24, 2008 2:57 am
- Location: US
Found what looks like a good "electromagnetics for non-EE majors" book, for those interested in cutterhead design experimentation...
"Electromechanical Devices & Components Illustrated Sourcebook", Brian Elliott
the book is US $71.96 new, but they have used copies starting around $40 on Amazon.
The amazon page lets you "look inside" & see the table of contents which includes all the basics of electromagnetics as well as design of all types of electric motors & other electromagnetic devices, including loudspeakers, microphones, & similar transducer devices:
http://www.amazon.com/Electromechanical-Devices-Components-Illustrated-Sourcebook/dp/0071477527
[EDIT] Got the book - its great, has all necessary info for getting started in home cutterhead design experimentation
- Bob
Last edited by blacknwhite on Sun Dec 21, 2008 2:03 am, edited 2 times in total.
Have you looked into the books published by Lindsay's?
http://www.lindsaybks.com/
They publish a wealth of info on lost art subjects. A few titles to look at:
Old-Time Secrets of Making Permanent Magnets
Soleniods, Electromagents, & Electromatnetic Windings
Coil Winding Machine
Gingerly's Magneto Magnetizer
I have the second and third sources cited and they are a great resource. There is some math involved, but if you are getting into this, you have to be prepared to get into the details.
P.S. I've built a lathe from scratch using off the shelf Home Depot parts and an old Presto T-18 turntable. I built a stereo cutter head using small speakers I found available from Mouser. Not super results, but I intend to refine it. I now have a Presto 6N/ 1-C and want to eventually adapt my head to it. I am also getting pretty good at lapping my own cutting stylii using 1/16" HHS drill blanks. I recently purchased some saphire .032" X .380" rod stock and will try lapping these and inserting into a 1/16" aluminum shank.
http://www.lindsaybks.com/
They publish a wealth of info on lost art subjects. A few titles to look at:
Old-Time Secrets of Making Permanent Magnets
Soleniods, Electromagents, & Electromatnetic Windings
Coil Winding Machine
Gingerly's Magneto Magnetizer
I have the second and third sources cited and they are a great resource. There is some math involved, but if you are getting into this, you have to be prepared to get into the details.
P.S. I've built a lathe from scratch using off the shelf Home Depot parts and an old Presto T-18 turntable. I built a stereo cutter head using small speakers I found available from Mouser. Not super results, but I intend to refine it. I now have a Presto 6N/ 1-C and want to eventually adapt my head to it. I am also getting pretty good at lapping my own cutting stylii using 1/16" HHS drill blanks. I recently purchased some saphire .032" X .380" rod stock and will try lapping these and inserting into a 1/16" aluminum shank.
- blacknwhite
- Posts: 483
- Joined: Thu Apr 24, 2008 2:57 am
- Location: US
Awesome, thanks for the info! That's the exact path I'm looking to go down, including sapphire rod stock. In the mean time, i've purchased a stock of used sapphire metal-shank needles for resurfacing, but no time/lapping tools yet to get started with. Saved lots of pics, videos & plans from online for building gem faceting machines & plan to modify to make more high-precision.markrob wrote:P.S. I've built a lathe from scratch using off the shelf Home Depot parts and an old Presto T-18 turntable. I built a stereo cutter head using small speakers I found available from Mouser. Not super results, but I intend to refine it. I now have a Presto 6N/ 1-C and want to eventually adapt my head to it. I am also getting pretty good at lapping my own cutting stylii using 1/16" HHS drill blanks. I recently purchased some saphire .032" X .380" rod stock and will try lapping these and inserting into a 1/16" aluminum shank.
No, I hadn't found that series of books you mentioned yet, thanks, will check it out! You mentioned Gingery - I've been picking up some of David & Vencent Gingery's series of books (amazon & elsewhere) on building metalworking tools from scrap metal parts / old washing machine motors / etc, including how to build a fullsize working metalworking lathe, and thermoplastic injection molding (modifiable to pressing)... Inspiring for building a higher-precision, somewhat smaller, record-cutting lathe & other stuff.
Great relatively-cheap retail source of surplus electromechanical parts, large & small:
Surplus Center http://www.surpluscenter.com/
Your projects sound GREAT. When you get something you're sufficiently proud of, please post pics and.or video. You're way ahead of me in terms of finding time to "go and do it"! I'd especially like to refine a "Presto-fidelity" 3-speed cutter to the point that it's economically feasible for me to cast the parts out of metal and/or plastics for small-scale "mass production" at home as a hobby, for resale to hobbyists/general public at much lower costs than current going rates.
Fun stuff, just need to invent a time-generator...
- Bob
Hey Bob,
Sounds like we have a great deal in common. I just put up a simple web site with some pictures. I can add some better shots if you are interested.
http://home.comcast.net/~markrob1066/site/[url/] For lapping I'm using a home brew base with a Inland swap top and one 1200 grit diamond lap (not the whole kit shown). The swap top runs about $30 and the lap was another $40. You also need an master lap and arbor. All told, a bit over $100 got me going. After rough grinding, I flip the lap over and use the blank side to polish to a mirror finish using 14000 grit diamond powder. I then wind a few turns of .005" Nichrome wire for heating. [url]http://www.inlandcraft.com/singleproduct.asp?position=5&department_id=17&keyword=&category=&partnum=10685[url/] I'm using a simple template faceter that does not require a precision head. The angles are set with wood blocks and a simple template. There are plans available here: [url]http://www.thegemconnection.com/faceting/index.htm
Sounds like we have a great deal in common. I just put up a simple web site with some pictures. I can add some better shots if you are interested.
http://home.comcast.net/~markrob1066/site/[url/] For lapping I'm using a home brew base with a Inland swap top and one 1200 grit diamond lap (not the whole kit shown). The swap top runs about $30 and the lap was another $40. You also need an master lap and arbor. All told, a bit over $100 got me going. After rough grinding, I flip the lap over and use the blank side to polish to a mirror finish using 14000 grit diamond powder. I then wind a few turns of .005" Nichrome wire for heating. [url]http://www.inlandcraft.com/singleproduct.asp?position=5&department_id=17&keyword=&category=&partnum=10685[url/] I'm using a simple template faceter that does not require a precision head. The angles are set with wood blocks and a simple template. There are plans available here: [url]http://www.thegemconnection.com/faceting/index.htm
- blacknwhite
- Posts: 483
- Joined: Thu Apr 24, 2008 2:57 am
- Location: US
SWEET! That Rocks.
Like, I said, other priorities of mine currently are blocking (i.e. day work, night classes, career change) so I've only enough free time to be in "info collecting mode"... so, I'm all talk and no DO far as Vinyl goes right now... great to see someone DOING this stuff.
THANKS for the sources, and the awesome pics Funny, I'd also chosen the aluminum-diaphragm tweeters for my planned future projects; got the 40w ones. Was going to try machining & soldering a ring to go around the dustcap area of the tweeter, to three tiny aluminum beams converging to a point, rather than a cone, but otherwise, same plans.
I'n a huge fan of true mono so planned my first head to be mono with single tweeter and precision point-bearing low-mass mechanical linkage to convert from vertical motion to lateral (similar to victrola soundbox linkage but with needle chuck pointing at a right angle from the pivot joint, pointing in same direction as diaphragm face, and lower-mass smaller shorter linkage arms)
Keep up great work!
- Bob
Like, I said, other priorities of mine currently are blocking (i.e. day work, night classes, career change) so I've only enough free time to be in "info collecting mode"... so, I'm all talk and no DO far as Vinyl goes right now... great to see someone DOING this stuff.
THANKS for the sources, and the awesome pics Funny, I'd also chosen the aluminum-diaphragm tweeters for my planned future projects; got the 40w ones. Was going to try machining & soldering a ring to go around the dustcap area of the tweeter, to three tiny aluminum beams converging to a point, rather than a cone, but otherwise, same plans.
I'n a huge fan of true mono so planned my first head to be mono with single tweeter and precision point-bearing low-mass mechanical linkage to convert from vertical motion to lateral (similar to victrola soundbox linkage but with needle chuck pointing at a right angle from the pivot joint, pointing in same direction as diaphragm face, and lower-mass smaller shorter linkage arms)
Keep up great work!
- Bob