John Curl's Blowtorch preamplifier part II

[Kindhornman]

Back to the teflon insulation I am wondering if there are any advantages at all in using that wire insulation for certain instances, and I understand JN's concerns with creep and failure of the insulation, would there ever be a practical application where the teflon was coextruded with another material outside of the teflon? I haven't looked if that is even possible with the different melt temperatures and material compatibilities but am just curious.

 

[iko]

Gentlemen, nobody likes disrespect, and we will not tolerate it. So, please maintain your decency. Let's get back to our regular schedule now.

 

[SY]

Back to the teflon insulation I am wondering if there are any advantages at all in using that wire insulation for certain instances, and I understand JN's concerns with creep and failure of the insulation, would there ever be a practical application where the teflon was coextruded with another material outside of the teflon? I haven't looked if that is even possible with the different melt temperatures and material compatibilities but am just curious.

Not so easy. PTFE is a bear to extrude, it takes high temps, creates corrosive gases (extruder barrel and die materials are critical, and wire has to be silver or silver plated) and, as advertised, sticks to nothing.

 

[Kindhornman]

Thanks Sy,
I assumed you would know that answer, extrusion is something I haven't had to deal with but I understand what you are saying.

 

[wrinkle]

Most of it is made offshore now and labour isn't even a consideration when you guys are paying by the piece to the OEM production house!

Oh wait... You're concerned about ATI's labour costs? Do they not quote a production run based on unit count to come up with a cost per unit?

Yeah I'm sure labour is built into that but it sure as hell isn't on your books is it less R&D.

You have not yet realised that JN does not sell stuff on here, this is hobby time for him, me and many others.

The Teflon comment I made earlier, was written with sloppy english, the triboelectric problems with teflon are problems at any temperature, but at 200C your choice of plastics is more limited.

 

[SY]

Thanks Sy,
I assumed you would know that answer, extrusion is something I haven't had to deal with but I understand what you are saying.

Yeah, unfortunately, I've put in my time at wire factories.

 

[jan.didden]

As for an article, I would be honored but Jan wouldn’t be. He does well keeping the standards of his magazine high.George

You're to modest George. Even SY writes for L|A

Between you and me, why don’t you…?
George

Yeah why don't you jn?

Jan

 

[gpapag]

You're aerospace right?
I have a friend that does maintenance on large commercial aircraft and he told me on a "refit" they rip the entire cabin apart and remove a lot of cable segments.
Are you trying to tell me he's soldering those wires like you guys doing your AV design work to PCBs?

I was in aerospace sector.
Anything (OK, 99,99% of it) external to the boxed electronic units is crimped joints, not solder joints.
As for the choise of wire insulation material, in the last two decades, it is more of flammability/smoke toxicity pass test. Specs get stringer year after year.
http://www.fire.tc.faa.gov/pdf/TN04-32.pdf

But whatever the subject under discussion, try to behave (you are drifting)!!!

George

 

[jneutron]

Yeah why don't you jn?
Jan

Check your mailbox. Gimme some FB..

jn

 

[gpapag]

You're to modest George. Even SY writes for L|A
Yeah why don't you jn?
Jan

It is about ‘delivering’ Jan, not modesty.
SY, jn, Scott, Pavel, they can deliver the essentials .
I can do the question marks.

George

 

[DF96]

you characters!

If you want to insult people it is helpful to identify them. If not, they might not notice the insult and others may unnecessarily take offence. Better still, do more lurking on here so you have a better idea who you are talking to. Then you might feel less need to reach for the rude button. Some of the people on here are acknowledged experts in their own field. We argue amongst ourselves but we do try (not always successfully) to attack the issue and not the person.

 

[scott wurcer]

I read that "white paper" on Bybee's site and it's a steaming pile of ____.

Best not bother, we have beaten that one to death.

 

[elektroj]

Not so easy. PTFE is a bear to extrude, it takes high temps, creates corrosive gases (extruder barrel and die materials are critical, and wire has to be silver or silver plated) and, as advertised, sticks to nothing.

Re. silver/silver plated - that was my impression too, but what about the Teflon insulated pure copper cables that are sold on audiophile market? Kimber TCSS comes to mind.. Do they have some secret recipe?

 

[john curl]

They must have.

 

[fas42]

Teflon, however, does NOT necessarily make a great cable. I once ordered some Teflon cable for a laser control system that was recommended to me by an associate at LBL.
The wire was pure white, coax, small, flexible, reasonably priced, and had a 5,000V breakdown (this was important in my application).
I tried to make audio cables from it, just to try, and they wound up sounding LOUSY!

If someone went to substantial effort, and worked out precisely what was happening here, I feel a great deal would be learnt ...

 

[SY]

Re. silver/silver plated - that was my impression too, but what about the Teflon insulated pure copper cables that are sold on audiophile market? Kimber TCSS comes to mind.. Do they have some secret recipe?

Looking at Kimber's site, they are careful not to say Teflon. It appears that the wires are coated with a cheaper, lower temperature fluorocarbon, not PTFE (e.g., Tefzel, Kynar...). The wires in their photos have clear insulation- PTFE is very cloudy-to-white.

 

[DF96]

near-Teflon?

 

[SY]

No, I don't think there's superconductivity involved.

 

[elektroj]

Looking at Kimber's site, they are careful not to say Teflon. It appears that the wires are coated with a cheaper, lower temperature fluorocarbon, not PTFE (e.g., Tefzel). The wires in their photos have clear insulation- PTFE is very cloudy-to-white.

Good observation, SY. All others are still talking about Teflon..

Kimber Kable 8TC

Kimber TCSS Hookup Wire, Per Foot

 

[SY]

Moral: go right to the source.

One other possibility is that they're using something like the amorphous AF grades, which can be applied at a lower temperature, but at the cost of already-poor mechanical properties.