The AM Forum
March 29, 2024, 04:59:43 AM *
Welcome, Guest. Please login or register.

Login with username, password and session length
 
   Home   Help Calendar Links Staff List Gallery Login Register  
Pages: [1]   Go Down
  Print  
Author Topic: black Nylon  (Read 5441 times)
0 Members and 1 Guest are viewing this topic.
aa5wg
Member

Offline Offline

Posts: 435


« on: July 19, 2011, 06:29:19 AM »

Hi to all:
Is black nylon (i.e. washers, nuts and bolts) a safe material for use at HF and high power. i.e. building RF coils for antenna tuners.
Chuck
Logged
kg8lb
Guest
« Reply #1 on: July 19, 2011, 07:43:51 AM »

Black Nylon ?

 Sure looks good with short skirts and high heels.

  However, not real good in RF fields. Ok as fasteners etc depending on use/location.  Delrin (not delrOn) is a better choice.
Logged
Ralph W3GL
Contributing
Member
*
Offline Offline

Posts: 748



« Reply #2 on: July 19, 2011, 04:12:20 PM »



   Chuck, to do a quick check of the nylon hardware for use in an RF environment
   stick a sample of what you want to use in the microwave oven  for a few seconds
   at full power  Shocked Shocked.  If the sample gets warm it is no good for the job... Roll Eyes Roll Eyes

Logged

73,  Ralph  W3GL 

"Just because the microphone in front of you amplifies your voice around the world is no reason to think we have any more wisdom than we had when our voices could reach from one end of the bar to the other"     Ed Morrow
kg8lb
Guest
« Reply #3 on: July 19, 2011, 04:58:48 PM »

 Nylon is hygroscopic so the reaction may vary with moisture content. (From some reports) Delrin is a more stable material. Although it looks a lot like Nylon it is a totally different material.
Logged
KL7OF
Member

Offline Offline

Posts: 2313



« Reply #4 on: July 20, 2011, 10:54:07 AM »

Black Nylon ?

 Sure looks good with short skirts and high heels.

  However, not real good in RF fields. Ok as fasteners etc depending on use/location.  Delrin (not delrOn) is a better choice.

I like the ones with the seam running down the back
Logged
kg8lb
Guest
« Reply #5 on: July 20, 2011, 07:41:22 PM »

Black Nylon ?

 Sure looks good with short skirts and high heels.

  However, not real good in RF fields. Ok as fasteners etc depending on use/location.  Delrin (not delrOn) is a better choice.

I like the ones with the seam running down the back

Yep !

  Seriously though , I repeat:
However, not real good in RF fields. Ok as fasteners etc depending on use/locationDelrin (not delrOn) is a better choice.
Logged
W7TFO
WTF-OVER in 7 land Dennis
Contributing
Member
*
Offline Offline

Posts: 2521


IN A TRIODE NO ONE CAN HEAR YOUR SCREEN


WWW
« Reply #6 on: July 20, 2011, 08:05:47 PM »

To get to your original question, commercial RF inductors are held together with nickle plated brass or stainless hardware, and have washers of fiber, porcelain, or plastic in between so as to not make a connection across the coil end supports. 

Those supports usually are of aluminum strap and form a triangle or square to hold the turns spacer bars in place. 

The same bolts usually pierce the turns spacer material, and this arrangement makes for secure construction with no eddy currents.  These bolts do not form part of the RF current-carrying metal, as that is usually a separate fastener thru the turns spacer bar holding a soldered lug from the end of the coil.

Where you get into trouble is making RF go thru ferrous hardware and multi-metal joints.  Use plated brass or stainless for that, and don't worry too much about support hardware getting too hot from induction.  Most of it will be too small to react to the field.

Don't use plastic hardware for any job that must stay torqued, such as that carrying RF across a joint.

73DG
Logged

Just pacing the Farady cage...
aa5wg
Member

Offline Offline

Posts: 435


« Reply #7 on: July 22, 2011, 10:31:23 AM »

DG and all:
Thank you for your helpful information. 
Chuck
Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
 AMfone © 2001-2015
Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
Page created in 0.054 seconds with 18 queries.