If you are new to pulse motors,and are going to build the standard SSG-know that if built the way JB describe's,you have just built the worst possible configuration.If you make it so as the coil end that faces the rotor magnets,is fireing a north field,and the rotor also has the north field's facing out,your soft iron(steel rod) core will become magnetised,and the efficiency of the motor will slowly degrade.
There is two simple fixes for this.
1-reverse the polarity of both the run coil,and trigger coil,so as your motor become's an attraction motor.The coil will then be fireing a south field at the rotor end,and the rotor magnets remain north.This will help stop the core becoming magnetised.
2-Simply turn the magnets around on the rotor,so as the south field faces out,while leaving the coil as is(standard ssg)
Another improvment i have found is-dont rap your two wires on together. First wind the trigger coil on (.4-.5mm wire is best for 12 volts)Dont worry to much about how many turn's,just wind on 4 layers as neat as possable.Then use thread tape,and lay on one layer of thread tape over the trigger coil. Then 8 layer's of .6 or .71mm wire over the top. Make your coil core 3/4 inch by 2 1/2-3 inches long. Use 1/2 inch wide x 3/4 inch long neo magnet's in the rotor.
If using a lot of magnets in the rotor that will be closer than 2 inches together-alternate the fields N/S/N/S. This will insure the transistor switches cleanly,and will run cold.

Mmm-maybe i should write my own book,on how to build a decent machine lol.

lol @einstein.it baffles you because there is a possibility that they can do exactly that.

I remember analyzing the "10 coiler."  It was very crudely designed.  I got into a debate with a guy named Jeff that bought a 10-coiler and had battery banks and a computerized swapper and a grid-tie inverter, the whole nine yards.  He was going to draw energy from the system while the 10-coiler was swapped back and forth between the two banks to "keep the self-charging going." 

I told him it would never work and he scowled at me and I scowled back.  He couldn't answer my basic questions about the characteristics of his 10-coiler and scowled at me some more.

I lost track or he disappeared or both.  However, about a year later he made a posting trying to sell his 10-coiler.

So Jeff bought into the myth, and then spent a lot of his money and time and energy.  At one of the Bedini conferences there was even a projected animation of a house with a Bedini motor and a bank swapper powering a home.  But of course we all know that if anybody asks the question directly to Bedini or one of his minions then they always say that they never claimed a Bedini motor is a free energy device.  Some may remember the episode of the "leaked clip" with a Renaissance solar charger that was allegedly over unity, Bedini himself stated it in the clip, and the story of how that one played out.

So Jeff was a victim, even if he was a willing victim at the start.  He spent lots of money and was writing the code for the battery swapper, etc, etc.   I asked him to test it manually without the computerized swapper but he wouldn't listen to me.  All of his time, money, energy, and thought process lost for no good reason.  Poor guy, he really got burned.

Would you buy a used Ferris Wheel motor from Jay Bee?  One caveat, you can't live on the equator.  lol