If you need assistance, please send an email to forum at 4hv dot org. To ensure your email is not marked as spam, please include the phrase "4hv help" in the subject line. You can also find assistance via IRC, at irc.shadowworld.net, room #hvcomm.
Support 4hv.org!
Donate:
4hv.org is hosted on a dedicated server. Unfortunately, this server costs and we rely on the help of site members to keep 4hv.org running. Please consider donating. We will place your name on the thanks list and you'll be helping to keep 4hv.org alive and free for everyone. Members whose names appear in red bold have donated recently. Green bold denotes those who have recently donated to keep the server carbon neutral.
Special Thanks To:
Aaron Holmes
Aaron Wheeler
Adam Horden
Alan Scrimgeour
Andre
Andrew Haynes
Anonymous000
asabase
Austin Weil
barney
Barry
Bert Hickman
Bill Kukowski
Blitzorn
Brandon Paradelas
Bruce Bowling
BubeeMike
Byong Park
Cesiumsponge
Chris F.
Chris Hooper
Corey Worthington
Derek Woodroffe
Dalus
Dan Strother
Daniel Davis
Daniel Uhrenholt
datasheetarchive
Dave Billington
Dave Marshall
David F.
Dennis Rogers
drelectrix
Dr. John Gudenas
Dr. Spark
E.TexasTesla
eastvoltresearch
Eirik Taylor
Erik Dyakov
Erlend^SE
Finn Hammer
Firebug24k
GalliumMan
Gary Peterson
George Slade
GhostNull
Gordon Mcknight
Graham Armitage
Grant
GreySoul
Henry H
IamSmooth
In memory of Leo Powning
Jacob Cash
James Howells
James Pawson
Jeff Greenfield
Jeff Thomas
Jesse Frost
Jim Mitchell
jlr134
Joe Mastroianni
John Forcina
John Oberg
John Willcutt
Jon Newcomb
klugesmith
Leslie Wright
Lutz Hoffman
Mads Barnkob
Martin King
Mats Karlsson
Matt Gibson
Matthew Guidry
mbd
Michael D'Angelo
Mikkel
mileswaldron
mister_rf
Neil Foster
Nick de Smith
Nick Soroka
nicklenorp
Nik
Norman Stanley
Patrick Coleman
Paul Brodie
Paul Jordan
Paul Montgomery
Ped
Peter Krogen
Peter Terren
PhilGood
Richard Feldman
Robert Bush
Royce Bailey
Scott Fusare
Scott Newman
smiffy
Stella
Steven Busic
Steve Conner
Steve Jones
Steve Ward
Sulaiman
Thomas Coyle
Thomas A. Wallace
Thomas W
Timo
Torch
Ulf Jonsson
vasil
Vaxian
vladi mazzilli
wastehl
Weston
William Kim
William N.
William Stehl
Wesley Venis
The aforementioned have contributed financially to the continuing triumph of 4hv.org. They are deserving of my most heartfelt thanks.
Registered Member #3637
Joined: Fri Jan 21 2011, 11:07PM
Location: Buffalo, NY
Posts: 1068
Never mind. I tried heating it up with an oven, to get rid of moisture in the cardboard, and the entire tube shrunk as a result. All that magnet wire came loose and basically 4-5 hours of work lost.
Registered Member #480
Joined: Thu Jul 06 2006, 07:08PM
Location: North America
Posts: 644
Inducktion -
Don't feel bad, I did the same thing a long ago, only with two secondaries at the same time.
I had wound a pair of 3" X 12" secondary coils on thin wall PVC pipe with fine gage wire for a bipolar-twin setup; both had been carefully matched with exactly the same resonant frequency. I decided to place them in a "warm" oven for a few hours prior to epoxy coating them to make sure that they were dead dry.
I removed the oven racks, set the temperature knob on the electric oven to the "warm" setting, let it warm up for 15 minutes or so, and turned the heat off. I opened the door (the oven felt only moderately warm inside), and carefully placed both secondaries vertically on the floor of the oven.
I came back 15 minutes later to check on the coils, and everything was perfect. I came back about two hours later, and was horrified to see that much of the the wire had slipped down the coilforms, and was overlapped and lumpy, with gaps every 1/4" or so.
I think what happened was that the the PVC expanded with the heat, and stretched the #30 wire ever so slightly. When the PVC cooled and shrank, the now-stretched wire was loose enough to slide down the coilform and overlap the lower turns. I thought I could somehow "salvage" the coils by sliding the "slipped" turns back into place, but it was useless, and I had to strip all the wire off both coils and scrap it all.
Lesson learned: don't heat ANY coilform with a high coefficient of thermal expansion (e.g. any plastic pipe or tubing) after being wound with fine gage wire.
I did hear one report where someone stored an uncoated secondary wound on a 6" PVC pipe in an unheated garage during a cold winter, and it suffered the same slipped-turn fate because the coilform shrank so much in the ice-cold garage.
Registered Member #3450
Joined: Sun Nov 28 2010, 05:01AM
Location:
Posts: 61
Inducktion
That really sucks!!! If your looking for a good source of free magnet wire try a 120v bathroom fan. The wire on the motor is on a nice bobin and easy to remove. Also inside a microwave, the fan motor is the same with a good supply of mag wire.
PS. Remember to coat your wire with some clear polyurethane spray paint right after winding.
Registered Member #3637
Joined: Fri Jan 21 2011, 11:07PM
Location: Buffalo, NY
Posts: 1068
I've got another relay to use, and the wire looks a few gauges thinner than the stuff I used before. I think I'm going to try a slightly smaller coilform as well, and use something more...durable, like PVC.
This site is powered by e107, which is released under the GNU GPL License. All work on this site, except where otherwise noted, is licensed under a Creative Commons Attribution-ShareAlike 2.5 License. By submitting any information to this site, you agree that anything submitted will be so licensed. Please read our Disclaimer and Policies page for information on your rights and responsibilities regarding this site.
My first Telsa coil secondary...
