Knob & Tube Insulators

[Roy K8VWX]

        I have a Ham friend looking for a couple of 10 or 12 inch crock tubes to bring open wire feeders into his shack. Any one have any laying around or what would be another choice of material for such??  TNX / k8vwx

[KB5MD]

I use the hot water type of PVC pipe.  The outside diameter is about 1/2"

[Roy K8VWX]

     Years ago I was running my BC 610 on a multiband open wire fed antenna using latter line out of the soffit of my garage with some PVC material as feed through insulators and had serious RF flashovers. The wood around the PVC tubes was very badly  charred. Could have burned the garage down. ( The tubes were closely spaced ) 

[KA0HCP]

http://www.daburn.com/10-67metalbaseinsulators.aspx

Daburn.com has many types of ceramic insulators.

http://www.daburn.com/10-30steatiteconeinsulators.aspx

[W3GMS]

        I have a Ham friend looking for a couple of 10 or 12 inch crock tubes to bring open wire feeders into his shack. Any one have any laying around or what would be another choice of material for such??  TNX / k8vwx

Roy,

I have always used big ceramic feed though insulators.  I throw away the bolts that come with them and get some "all thread rod".    If you drill things properly, the rod will not touch anything since its centered in the middle of the ceramic feed through.  Put that in about 40 years ago and still working very well.

Joe, GMS

[W1RKW]

Glass tubing inside of PVC

[Detroit47]

Teflon tubing is a  stable and just about arc proof material to use.
http://www.professionalplastics.com/Teflon_PTFE

http://www.polyzone.com/products/rods-tubes-profiles/ptfe-teflon-rod-tube

[Roy K8VWX]

         Thanks Guys for all the good input. I will pass this on to my friend in Tennessee. I think he is running SSB now but is very interested in AM also. 73 / Roy