Film-Tech Forum ARCHIVE: Worst shock you have given?

This is topic Worst shock you have given? in forum Film-Yak at Film-Tech Forum ARCHIVE.

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Posted by Freddie Dobbs (Member # 915) on 10-04-2001, 07:50 AM:

Will's post about the toilet seat got me thinking, Whats the worst shock you have given someone? I am not proud to say that I hooked a plug wire to a bike that did not have grips on it, talked my little brother into holding the handle bars then pulled the cord...

Posted by Rick Long (Member # 213) on 10-05-2001, 12:07 AM:

Gord McLeod and I have previously discussed, on the forum, various tortures we like to inflict on apprentice projectionists.

One of the nastiest tortures we both enjoyed was in telling a newbie that the static discharge he got while inspecting film on the rewind could be cured by clamping an alligator lead with one end to the grounded rewind table, and the other end to the metal tag on his fly.

Posted by John Pytlak (Member # 331) on 10-05-2001, 08:27 AM:

Rick Long said: "...the static discharge he got while inspecting film on the rewind could be cured...".

Hopefully getting shocks while rewinding film is now a rare occurance, since Kodak VISION Color Print Film has a transparent conductive backing layer to help dissipate any static charge buildup. Fewer shocks, and prints stay cleaner.
http://www.kodak.com/US/en/motion/products/lab/2383.shtml

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John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Research Labs, Building 69, Room 7525A
Rochester, New York, 14650-1922 USA
Tel: 716-477-5325 Cell: 716-781-4036 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com
Web site: http://www.kodak.com/go/motion

Posted by Jerry Chase (Member # 660) on 10-05-2001, 01:03 PM:

Since Kodak VISION Color Print Film has a transparent conductive backing layer, can we use the film as wiring? What happens when a strip of film drops across a couple of unprotected leads? Will interweaving two reels of the film make a big capacitor? Is there a standard resistance per foot of film, so that custom resistors could be made out of trailers? Inquiring minds want to know.

Posted by John Pytlak (Member # 331) on 10-05-2001, 01:15 PM:

The resistivity is on the order of about 10**9 ohms per square (a measure of internal resistance). Won't carry much current at the lower voltages used for power, but very effective in dissipating thousands of volts of static charge.

An equivalent application is the conductive plastic bags used to shield sensitive packaged circuit boards from static.

Try this test: rub a piece of processed KODAK VISION Color Print film through a dry cloth and try to pick up some cigarette ashes with the static charge. Now try it with an older print, or with "no name" print stock sometimes used for ads. The difference in dirt attraction is quite remarkable.

Posted by Randy Stankey (Member # 64) on 10-06-2001, 12:14 AM:

So, then, could we use a loop of cheap, "no name" film from an old trailer as the friction band in a Van de Graff generator?

Posted by JC Cowles (Member # 914) on 10-06-2001, 04:24 AM:

The worst shock I've ever received is by grabbig a toaster by the slots. But I saw a 350 pound woman touch a 220volt bare wire and knock a hole in a walkin freezer.

Posted by Freddie Dobbs (Member # 915) on 10-06-2001, 09:15 AM:

Hey, we have found an alternative power sourse.. old prints......

Posted by Steve Guttag (Member # 268) on 10-06-2001, 10:11 AM:

>>" Try this test: rub a piece of processed KODAK VISION Color Print film through a dry cloth and try to pick up some cigarette ashes with the static charge."<<

Now wait a minute John....just where does one get this cigarette ash?

Steve

Old projectionists never die, they just pick up cigarette ash!

Posted by John Pytlak (Member # 331) on 10-06-2001, 07:43 PM:

Steve, thanks for reminding me there are no cigarette ashes in a well-run projection room!

So take the strips of film outside to run the experiment. If you don't smoke, use fresh coffee grounds or shredded styrofoam as "dirt".

Randy: Yes, non-conductive film will make an excellent belt for a VDG generator.

Posted by Steve Guttag (Member # 268) on 10-07-2001, 02:41 AM:

But John....

I don't smoke (except out my ears) and I don't drink coffee! So now what? This is starting to get complicated!

Steve

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"Old projectionists never die, they just changeover!"

Posted by Randy Stankey (Member # 64) on 10-07-2001, 09:24 AM:

Lycopodium powder?

Posted by John Pytlak (Member # 331) on 10-08-2001, 11:30 AM:

Steve --- tear open a full vacuum cleaner bag to get "dirt" for your static experiment (outside of the projection room please!)

Posted by Brad Miller (Member # 2) on 10-08-2001, 01:49 PM:

Something tells me Steve does not have carpet in his booth, and as such will not have a vacuum cleaner bag.

Posted by Will Kutler (Member # 770) on 10-08-2001, 03:59 PM:

Tellin' a hair raising story to a bald headded man!

Posted by Randy Stankey (Member # 64) on 10-08-2001, 04:34 PM:

How about sprinkling some flakes of ground pepper on a sheet of paper?

Again, Lycopodium powder, the spores of the lycopodium fern, which are used as a form of flash powder; a means of preventing pills and capsules from sticking together in the bottle; and as an herbal medicine might also be a good test for static electricity. It's a fine, yellow powder which, if spread in a thin layer on a piece of paper might be picked up by a static charged surface.

In my science classes in high school, we used both of these methods. Then we sucked the lycopodium up into a pipette and puffed it into a lit bunsen burner.