[TowerTalk] OT: Bonding to Teflon

[Larry McDavid]

"Glue" is historically made from animal products. Modern bonding agents 
are "Adhesives." You will get better search results if you use "adhesive."

"Teflon" is a brand name and applies to several chemically-different 
forms. One common form is TFE and is white in color. But, FEP is also 
common and not usually white. Both types cold flow under load so will 
change shape unexpectedly.

Neither TFE nor FEP can be adhesively bonded. You might get a 
"mechanical" bond if the Teflon surface is somewhat rough but not a 
chemical adhesive bond.

A mastic adhesive like that on thick double-sided tape will show some 
adhesion to Teflon but not a chemical bond. It might be enough if the 
load is low.

But, you can treat the Teflon surface to make it chemically active and 
bondable with common adhesives, including epoxy. The most common 
treatment chemical is sold as, "Tetra-Etch" and a simple Google search 
will turn up many results. But, beware, it is pretty nasty stuff. Amazon 
does not sell it. I've used lots of Tetra-Etch over many years and it 
definitely works; it makes the Teflon surface adhesively bondable, at 
least at moderate bond strengths. It turns the white TFE surface a light 
to dark gray in color. The etched surface has reasonable, but not 
indefinite, active life; you really want to adhesively bond the etched 
Teflon surface in a day or two at most.

My recollection is that Tetra-Etch contains an alcohol and sodium; 
disposal is not simple... But, it works!

Larry


On 7/9/2020 11:13 AM, Gedas wrote:
> Pardon the OT post but we have so many knowledgeable folks here I was 
> hoping I could get a quick answer.
> 
> This is antenna & RF related so maybe not super far off OT hi-hi.
> 
> I have a 1/16" thick 3"x3" sheet of Teflon that I need to "glue" to the 
> front of a uW horn antenna to keep water, dirt, bugs, etc out of it. Can 
> anyone tell me what type of adhesive is known to adhere to Teflon and is 
> not too difficult to acquire? TU
> 
> Gedas, W8BYA EN70JT
-- 
Best wishes,

Larry McDavid W6FUB
Anaheim, California  (SE of Los Angeles, near Disneyland)