Marvelous Magnetic Machines: Building Model Electric Motors from Scrap
You’re standing in front of an old card table in a driveway at a garage sale. On that table is a one-quart aluminum saucepan, a votive candle holder, pieces of some office machinery, and a wooden awards plaque. What do you see there? If you did not answer “a six-cylinder radial electromagnetic attraction motor,” then you need this book! H.P. Friedrichs (author of The Voice of the Crystal and Instruments of Amplification) returns this time to explore the principles behind the operation and construction of five simple, yet impressive, model electric motors. Aspiring mechanical model makers are often discouraged by their lack of access to machine tools, like mills, lathes, or drill presses. Friedrichs demonstrates that with some basic knowledge, an open eye, and a sharp mind, one can use commonly available (and often discarded) parts and materials to engineer one’s way around any lack of expensive machine tooling. In fact, every motor in this book was built from scrap, and can be assembled with hand tools. You’ll learn where to hunt for and find materials, and where to salvage suitable bearings. You’ll know where useful solenoids can be extracted from scrap, and how to fabricate bobbins to wind your own. You’ll learn how to time your motors, fashion a connecting rod, make a commutator from scratch, use a hall effect sensor to detect magnet position, use a transistor as a switch, and much more. Hardcover, 160 pages,177 photos and illustrations.
You’re standing in front of an old card table in a driveway at a garage sale. On that table is a one-quart aluminum saucepan, a votive candle holder, pieces of some office machinery, and a wooden awards plaque. What do you see there? If you did not answer “a six-cylinder radial electromagnetic attraction motor,” then you need this book!
H.P. Friedrichs (author of The Voice of the Crystal and Instruments of Amplification) returns this time to explore the principles behind the operation and construction of five simple, yet impressive, model electric motors.
Aspiring mechanical model makers are often discouraged by their lack of access to machine tools, like mills, lathes, or drill presses. Friedrichs demonstrates that with some basic knowledge, an open eye, and a sharp mind, one can use commonly available (and often discarded) parts and materials to engineer one’s way around any lack of expensive machine tooling. In fact, every motor in this book was built from scrap, and can be assembled with hand tools.
You’ll learn where to hunt for and find materials, and where to salvage suitable bearings. You’ll know where useful solenoids can be extracted from scrap, and how to fabricate bobbins to wind your own. You’ll learn how to time your motors, fashion a connecting rod, make a commutator from scratch, use a hall effect sensor to detect magnet position, use a transistor as a switch, and much more.
Hardcover, 160 pages,177 photos and illustrations.
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
Chapter III<br />
The Texas Motor<br />
Figure 3-1: The Texas<br />
Motor, front.<br />
Amateur Radio is a wonderful and instructive pastime. There is great fun in exercising<br />
the privilege to build, experiment with, and use radio transmitting equipment. Over<br />
the years, I’ve learned an awful lot, and met a lot of nice people. The ham radio fraternity<br />
is one immersed in a rich culture with longstanding traditions. One such tradition is the<br />
so-called “hamfest”.<br />
Hamfests are social gatherings where hams converge to buy, sell, and trade<br />
parts, equipment, and tall tales. Hamfests may be conducted in a community center, the<br />
conference room of a hotel, or in an unoccupied school building on a Saturday, but where<br />
I live, the weather is nice most of the time. Most of the hamfests I’ve attended have been<br />
conducted outdoors, in a parking lot or in an open field.<br />
One never knows what treasure may be found at a hamfest. Sellers cover their truck<br />
beds, tailgates, and folding tables with vintage radio transceivers, old tubes, antenna parts,<br />
recording equipment, computer parts, switches, wire, decommissioned military electronics,<br />
and who knows what else. Prices are often good, and many sellers like to haggle. It’s great<br />
fun for anyone who tinkers with electricity or electronics, ham operator or not.<br />
44
Change language