Teflon & Arlon Circuit Boards

PC board dielectrics

Several audio manufactures have used teflon boards. David Berning and Borbely Audio come to mind as two. Arlon is a cross woven PTFE(Teflon) material. Teflon is nasty to work when fabbing boards. It loves to break small drill bits. My board shop owner gives me unpleasant looks when I talk about it. The cost is WAY up there. Soldering to PTFE boards is fun too. The copper traces will lift from the board substrate very easily. I recommend a Polyimide material as more reasonable choice if a lower dielectric constant than FR-4 is wanted. The persnickity swear by point to point wiring...... That how I build my DIY audio projects.



Agreed. Moreover, the PTFE or fibre-reinforced PTFE is not as stiff as FR4 and causes the traces to craze and to break and, please, another person then shall seek the bug s in the intermittent circuit.
But i think it is a brilliant idea to use 5 mm thick Teflon as a carrier board for point-to-point wiring (sooo easy to be cut and machined) If Teflon is not stiff enough to carry the components, plywood will do fine for those components. Teflon is heavily damped and damping, getting down eventual µphony, a nice side effect.

And if elevated mounting or multiple soldering posts are required, combine this Teflon-board-based p-p wiring with ceramic soldering strips like used by Tektronix in the late 50ies and early 60ies. I have heaps of them, i slaughtered 5 or 6 old'n'dead Tek scopes to get them and many other fancy stuff.
<a href="http://www.rogers-corp.com/mwu/translations/prod.htm">Rogers Corporation, Microwave Materials Division</a>
RT/duroid® 5000 (PTFE/random microfiber glass),
Ultralam® 2000 (PTFE/woven glass)
RT/duroid® 6000 (PTFE/ceramic)
TMM® (Thermoset ceramic loaded plastic)
RO3000® and RO3200® (PTFE/Ceramic)
RO4000® (Woven glass/ ceramic loaded thermoset plastic resin)
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<a href="http://www.4taconic.com/dielctrc/Taconic%20Base%20Material.pdf">Taconic Advanced Dialectrics</a>
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<a href="http://www.rexolite.com/list.html">Rexolite®</a>(X-lined Polystyrene, Dielectric Constant 2.53 to 500Ghz) 1422 or 2200 copper thicknesses ranges from half ounce to two ounces copper.
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2001-04-07 10:03 pm

Yes, I had figured that out in the meantime. Got samples of that (4003) in a 12x9" copper-clad panel and also the RD/duroid 6002. The duriod 6002 is a much more expensive material, and has a lower dialelectric constant, but since I got it for free, should I use it instead of the 4003?

Thanks again,

-- Aaron Finley


2001-04-07 10:03 pm

Basically, I've narrowed my searches down to two types of Teflon-based substrates.

1) A highly-dimensional-stable dialectric with a X, Y, and Z pp/m stability similar to FR4. For instance, Taconic TLE and Rogers duroid 6002, both with dialectric constants of 2.90-2.95.

2) Or, a very low dialectric material such as Taconic TLY, but with more Y-axis flex, something like 280 PPm.

Also the 6002 does not require double etching.

So my question is, I'd like to use a material with the lowest dialectric constant, but is the high y-pp/m going to cause problems with a single-sided circuit?

Seems like the 6002 is a good compromise. (Anyhow FR4's constant is above 4 anyhow, so any of these are improvements, even 25N/4003, with 3.30, if I must)

Any thoughts?

-- Aaron Finley