Mayday ! "create your own spark project"

D. Bergeron · Post by **D. Bergeron** » Sat Feb 24, 2007 3:55 pm

I am helping my son with project, and it is completely built unable to generate magnetic field with primary coil. using 12 guage wire wrapped around small diametor bolt. Six winds on the primary there is no short to the bolt. using 13.8 volt DC power supply no magnetism at bolt head. What am I doing wrong?

LewisWhaley · Post by **LewisWhaley** » Sat Feb 24, 2007 5:04 pm

Hi D. Bergeron.

Please refer to Science Buddies Project:
"Create Your Own Spark"

Web page:

https://www.sciencebuddies.org/mentorin ... p027.shtml

The specifications for the bolt,
5/8th inch diameter bolt,
and
number of turns for the primary coil,
30 inches of 12 guage wire ,
need to be closer to the specifications as described on Science Buddies
web page.

The power supply should be,
preferably 1 or 2 Lantern Batteries,
and produce 6 volts DC to 12 volts DC.

The use of a power pack that converts your home's AC voltage to DC at 13.6 volts DC is not recommended by myself, in case this is being used.

The Lantern Batteries should be used for
portability and independence from an AC voltage source
such as the wall outlets in the home.

This is my recommendations.
I'm sure there will be many more.

Please let us know if this helps you with your son's project.

Good Luck!

D. Bergeron · Post by **D. Bergeron** » Sun Feb 25, 2007 7:41 am

Hi Lewis thanks for answering my question, but I have allready tried following the original specs. A 5/8 in. bolt with 30 in. of #12 wire minus the six in. to be removed for the spark gap gives you 12 turns on the primary. The pvc insulator that has to slide over this has a circumference of 3 in. usuing the 250 in. of enameled magnet wire in the specs. only gives you about 70 turns on the secondary. I used a 1/4 in. bolt with 10 turns on the primary. the pvc insulator that slides over primary has a circumference of 2in. I used 650ft. of #26 enameled magnet wire giving me approx. 5000 turns on the secondary. this ratio should produce 6000v. I am using a 13.8v DC power supply because the two batteries conn. in series only providing 11.5v. Voltage at primary is directly related to the magnetic field generated. I thought the extra 2v. would help. the magnetic field being produced is very weak unable to open conn. on the interrupter.

MelissaB · Post by **MelissaB** » Sun Feb 25, 2007 8:38 am

Hi,

I'm a Life Sciences forum expert and know nothing about electrical engineering so I can't really help--but there are several previous threads in this forum about this project where experts were able to help the posters. I have no idea if you have similar problems, but you might want to read those topics in case they give you ideas if you haven't already.

D. Bergeron · Post by **D. Bergeron** » Sun Feb 25, 2007 9:28 am

Hi Melissa, I really have tried reading everything that I could find on this subject. I am also not an electrical engineer. And my son who is in the sixth grade took on this project, which is really over both of our heads. I feel that our problem lies in the amount of magnetic field being produced. I have ajusted the interrupter so that it is as close as possible to the bolt head, and that the tension on the spring is as slight as I can get it. It is very difficult to try different things do to how delicate this swith is. I am wondering if the type of metal bolt will affect the amount of magnetic field produced. I am hesitant to try because the entire coil and interrupter would have to be taken apart. this project is do on the 28th of this month I am quickly running out of time.

Louise · Post by **Louise** » Sun Feb 25, 2007 2:55 pm

D. Bergeron wrote:Hi Melissa, I really have tried reading everything that I could find on this subject. I am also not an electrical engineer. And my son who is in the sixth grade took on this project, which is really over both of our heads. I feel that our problem lies in the amount of magnetic field being produced. I have ajusted the interrupter so that it is as close as possible to the bolt head, and that the tension on the spring is as slight as I can get it. It is very difficult to try different things do to how delicate this swith is. I am wondering if the type of metal bolt will affect the amount of magnetic field produced. I am hesitant to try because the entire coil and interrupter would have to be taken apart. this project is do on the 28th of this month I am quickly running out of time.

Yes, the type of metal is critical- one of our other experts mentioned in a different thread that the material of the bolt needs to be soft steel, not hard steel. If there is a hardness stamped on the top, it won't work.

The thread is at:
http://www.sciencebuddies.com/mentoring ... php?t=2328

Louise