OT: Has anyone tried this product for heat-sink compound?

[Barry]

"larry moe 'n curly" <larrymoencurly@my-deja.com> wrote in message
news:16d67a3d-32c5-43f5-84db-7751d0f1358c@k40g2000pro.googlegroups.com...

The Dr. is right, except for possibly one point: Ultra Copper does
NOT release acetic acid when it cures because it's instead alcohol-
based to be safe for use in cars equipped with exhaust oxygen
sensors. All of the Permatex silicone RTVs with the word "Ultra" in
their names are made for oxygen sensor compatibility, and all of them
smell like alcohol before they're cured. Also "Copper" refers only to
the color (actually reddish brown) and physical characteristics and is
not an indication of any copper content (none). BTW Permatex doesn't
produce silicone RTV in different colors merely for cosmetic purposes,
and many if not all of the colors indicate different physical
characteristics. For example, Ultra Copper is made to withstand
higher temperatures than any of their other RTVs, while Ultra Grey is
for gaskets with bolts that are close together, and they have others
made for withstanding gear oil or antifreeze:

You are correct. Permatex Ultra products are an alcohol cure. But they
still make two high temperature red silicones that are an acetoxy cure.
They, and the Ultra Copper silicones, are all brick red.

When I worked at Eastman Chemical Company's research labs, I was called
in to work on a problem with the thermocouples in their coal gasifiers.
Their maintenance people were using an acetoxy cure one-part GE red
silicone to encapsulate and insulate the "cold" end of the thermocouple
assembly. What they did not realize was that the silicone would only
cure to a depth of about 1/4 inch. The deeper material was uncured. I
had them switch to a two-part cure that did not create any volatile
byproducts that had to diffuse out through the cured "skin." I wish all
problems were so easy to fix.

This 1/4 inch issue can be a problem when a wide gasket is needed. The
material will cure along the outside edges, but still be uncured in the
middle. When the gasket gets hot, the uncured material can cause
localized over pressurization. If you forgetfully leave the cap off a
tube of silicone, a cured plug will form. This can usually be pulled out
allowing the rest of the tube to be used so try this before throwing the
tube away.

73, Barry WA4VZQ

 

[Barry]

"Bob Villa" <pheeh.zero@gmail.com> wrote in message
news:3eae9f09-2e5b-4b53-97f8-e53fb9cb8d94@x18g2000yqe.googlegroups.com...
On Apr 25, 8:28 pm, "Barry" <n...@nospam.org> wrote:

Are you the doctor that writes on nutrition?

No. In my case the "doctor" refers to my having a PhD. I am an oddball
having a PhD in chemical engineering while minoring in electrical
engineering and automatic control. At Eastman, I worked in a group that
designed and built custom instrumentation for their manufacturing
divisions. I later worked for W. L. Gore & Associates before retiring. I
have been on the Usenet newsgroups since 1983.

How many chemical engineers do you know that took graduate courses in
antennas and transmission lines? ;-)

Barry

 

[Jeff Liebermann]

On Mon, 25 Apr 2011 21:28:22 -0400, "Barry" <none@nospam.org> wrote:

If you go to a gardening supply and buy genuine Holland tulip bulbs, you
will likely get bulbs grown in Washington state. These bulbs are shipped
to the Netherlands and packaged. This allows them to be called "imported
from Holland."

When I was in Hawaii, the local Macadamia nuts were shipped to Los
Angeles, packaged, and shipped back for sales to the tourists.

Made in USA:
<http://en.wikipedia.org/wiki/Made_in_USA>
and from the FTC point of view, which is a confusing mess:
<http://business.ftc.gov/documents/bus03-complying-made-usa-standard>
<http://www.msnbc.msn.com/id/35821593/ns/business-us_business/>

Most pharmaceutical intermediates are today made in India or China, and
many drugs are totally made there and shipped to U.S. manufacturers who
compound the drugs with fillers and then stamp out the pills. They then
qualify as U.S. made pills.

It's possible to buy direct for India or China via various internet
vendors and spammers. The problem is that most of these don't contain
any of the advertised drugs. Great for a placebo, but not much else.

(...)
A number of generic drug manufacturers made it and a three
month supply cost less than $10. One "unnamed" pharmaceutical
manufacturer decided to go through the FDA testing and got it approved.
They then were able to get the FDA to force all the generic houses to
stop selling it. That three month supply is now well over $400. By the
way, these numbers are AFTER insurance.

This horror story is also at:
<http://en.wikipedia.org/wiki/Colchicine#Marketing_exclusivity>
Basically, the FDA gave them an exclusive in trade for paying for
their own drug tests, thus saving the FDA some budget money. Of
course, the FDA is defending their actions with various excuses but
never mentioning the cost to the public. However, they did release a
drug interaction warning at the same time probably intended to
convince the public that Colchicine is too dangerous to remain an
uncontrolled drug:
<http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalPRoducts/ucm174596.htm>

Drivel: I was synthesizing some of my own prescription drugs for a
while. The kitchen looked like Dr Frankenstein's laboratory.
Synthesis was generally successful, but I had only limited equipment
and ability to do potency tests. After two accidental overdoses, I
decided that this was not going to work. Even with the cost of all
the expensive reagents, glassware, and hardware, it was still cheaper
than paying retail for the drugs. Unfortunately, I can't deduct the
costs as a medical expense on my taxes. I managed to get one sample
tested and analyzed by a lab before they deduced what I was doing and
suggested I go elsewhere. However, now that I know the potency of
this one batch, I have the equivalent of a 20 year supply.

"Made in the United States of America" somehow doesn't mean what it once
did.

If we went on a protectionist tariff frenzy, and decide to "promote"
domestic manufacture, the prices of just about everything will go
dramatically higher. Given the choice, methinks Joe Sixpack would
chose to perpetuate the current mess. At this time "Made in USA"
means "you overpaid".

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com jeffl@cruzio.com
# http://www.LearnByDestroying.com AE6KS

 

[Bob Villa]

On Apr 25, 8:28 pm, "Barry" <n...@nospam.org> wrote:

"Bob Villa" <pheeh.z...@gmail.com> wrote in message

news:a42aa133-7d44-4573-85b0-6cf2fd911fb4@q32g2000yqn.googlegroups.com...
On Apr 24, 10:07 pm, "Barry" <n...@nospam.org> wrote:









"Bob Villa" <pheeh.z...@gmail.com> wrote in message

news:0a0e4aa2-74a4-4c20-bb66-5b2b021bec7f@u15g2000vby.googlegroups.com....

http://www.permatex.com/products/automotive/automotive_gasketing/gask....

It would "seem" to have good properties for filling minute gaps;
copper for heat transfer; can't dry-out; not a bonding type on
silicone.

Thanks
bob_v

This stuff is NOT a silicone grease but rather a room temperature
vulcanizing silicone rubber. There is no copper in it, and it is a poor
heat conductor. General Electric used to be the manufacturer, but it
appears that they have sold out to a Chinese company. If memory serves
it used to be either RTV-60, RTV-650, or RTV-106. I cannot remember
which is the two-part and which is the one-part material. MG Chemicals
is a distributor for Momentive Performance Materials, the _obviously_
Chinese company that makes it now. They do make two higher thermal
conductivity silicones known as TSE3331 and TSE3941. The former is a
grey potting and encapsulating compound while the latter is a white
adhesive.

~The tube I have says, "Made in USA".

I suspect Permatex used to buy from GE because their sales would be too
small to manufacture it themselves.  If you look for GE silicones, many
companies still stock them.  However if it is made in China and sold in
bulk and Permatex packages it for sale, I think they can get away with
calling it "Made in the USA."

If you go to a gardening supply and buy genuine Holland tulip bulbs, you
will likely get bulbs grown in Washington state.  These bulbs are shipped
to the Netherlands and packaged.  This allows them to be called "imported
from Holland."

Most pharmaceutical intermediates are today made in India or China, and
many drugs are totally made there and shipped to U.S. manufacturers who
compound the drugs with fillers and then stamp out the pills.  They then
qualify as U.S. made pills.

As you no doubt can tell, I am not very enamored with the pharmaceutical
industry.  I take colchicine for ankylosing spondylitis.  As a drug, it
has been around for over 2000 years and is normally used to treat gout.
My usage is "off-label" meaning it was prescribed for other than its
approved use.  My rheumatologist gave it to me for its anti-inflammatory
properties since my congestive heart failure prevents me from using
NSAIDs (non-steroidal anti-inflammatory drugs reduce your kidney
function).  A number of generic drug manufacturers made it and a three
month supply cost less than $10.  One "unnamed" pharmaceutical
manufacturer decided to go through the FDA testing and got it approved.
They then were able to get the FDA to force all the generic houses to
stop selling it.  That three month supply is now well over $400.  By the
way, these numbers are AFTER insurance.

"Made in the United States of America" somehow doesn't mean what it once
did.

        73, Dr. Barry L. Ornitz     WA4VZQ    ham_call_letters
live.com

Are you the doctor that writes on nutrition?

 

[Meat Plow]

On Mon, 25 Apr 2011 19:26:02 -0700, Jeff Liebermann wrote:

On Mon, 25 Apr 2011 21:28:22 -0400, "Barry" <none@nospam.org> wrote:

If you go to a gardening supply and buy genuine Holland tulip bulbs, you
will likely get bulbs grown in Washington state. These bulbs are
shipped to the Netherlands and packaged. This allows them to be called
"imported from Holland."

When I was in Hawaii, the local Macadamia nuts were shipped to Los
Angeles, packaged, and shipped back for sales to the tourists.

Made in USA:
http://en.wikipedia.org/wiki/Made_in_USA> and from the FTC point of
view, which is a confusing mess:
http://business.ftc.gov/documents/bus03-complying-made-usa-standard
http://www.msnbc.msn.com/id/35821593/ns/business-us_business/

Most pharmaceutical intermediates are today made in India or China, and
many drugs are totally made there and shipped to U.S. manufacturers who
compound the drugs with fillers and then stamp out the pills. They then
qualify as U.S. made pills.

It's possible to buy direct for India or China via various internet
vendors and spammers. The problem is that most of these don't contain
any of the advertised drugs. Great for a placebo, but not much else.

Dr. Reddy is a very popular Indian drug manufacturer. They make a lot of
USA store brand OTC, Ibuprofen for one. I've purchased antibiotics back
in 2007 from a legitimate online distributer and they were sealed boxes
in blister packs, pretty hard to counterfeit. And they worked. At the
time I was in between having prescription insurance coverage for a couple
months and I saved $150 bucks purchasing them from this internet company
who is still in business. The ones to watch out for are the Russian pill
spammers (Canadian Pharmacy) offering dick drugs and narcotics. The
company I dealt with offered neither. I researched the company and made
sure they were actually based in Canada. Also used Paypal. The drugs were
shipped directly from India.



--
Live Fast Die Young, Leave A Pretty Corpse

 

[josephkk]

On Sun, 24 Apr 2011 23:07:52 -0400, "Barry" <none@nospam.org> wrote:

Working around chemists, I had easy access to silicone vacuum stopcock
grease. I have used it in a pinch for thermal grease and it worked well.
You can find a similar grease in the plumbing department of Lowes and
Home Depot. It is used to lubricate valve stems, rubber seals, and those
ungodly expensive ceramic Price-Pfister faucets. It will work far better
than any Permatex product as a heat transfer grease.

Oh, and one other reason to not use Permatex in this application. This
silicone is an acetoxy cure which means it releases corrosive acetic acid
when it cures.

Ahem, not any more.

Dr. Barry L. Ornitz WA4VZQ ham_call_letters at live.com

Only the very old version from thee 1960s were acetoxy cure. I had a lot
of corroded connections to learn my lesson about that. Then in the early
1970s GE came out with the thixotropic variants which use atmospheric
moisture as an initiator. No more acid release as a byproduct of cure.
Please get up to date.

 

[Bob Villa]

On Apr 24, 10:07 pm, "Barry" <n...@nospam.org> wrote:

Oh, and one other reason to not use Permatex in this application. This
silicone is an acetoxy cure which means it releases corrosive acetic acid
when it cures.

        Dr. Barry L. Ornitz     WA4VZQ    ham_call_letters at live.com

Here is what I have used (in a pinch). And, no...I don't have stock in
Permatex. http://www.permatex.com/products/automotive/lubricants/specialty_lubricants/Permatex_Anti-Seize_Lubricant_a.htm

 

[GS]

On Apr 28, 2:01 pm, josephkk <joseph_barr...@sbcglobal.net> wrote:

On Sun, 24 Apr 2011 23:07:52 -0400, "Barry" <n...@nospam.org> wrote:

Working around chemists, I had easy access to silicone vacuum stopcock
grease.  I have used it in a pinch for thermal grease and it worked well.
You can find a similar grease in the plumbing department of Lowes and
Home Depot.  It is used to lubricate valve stems, rubber seals, and those
ungodly expensive ceramic Price-Pfister faucets.  It will work far better
than any Permatex product as a heat transfer grease.

Oh, and one other reason to not use Permatex in this application. This
silicone is an acetoxy cure which means it releases corrosive acetic acid
when it cures.

Ahem, not any more.



       Dr. Barry L. Ornitz     WA4VZQ    ham_call_letters at live.com

Only the very old version from thee 1960s were acetoxy cure.  I had a lot
of corroded connections to learn my lesson about that.  Then in the early
1970s GE came out with the thixotropic variants which use atmospheric
moisture as an initiator.  No more acid release as a byproduct of cure.
Please get up to date.

Permatex blue is electronic sensor safe, and I was using it in the
80's the cheapest of the electronic grade rtv.
I have used stopcock grease at times.
Regardless of type, but never used 1960 rtv, stuff WILL corrode under
silicone because of moisture build up, not acid corrosion. Clear
varnish should be applied to metal before rtv.
I have tested acidic rtv on foils. The vapor escapes rapidly unless
it's used in a closed box.

Greg

Greg

 

[isw]

In article <tiajr6d495fif2ggmqi23fi9me1mglcohu@4ax.com>,
josephkk <joseph_barrett@sbcglobal.net> wrote:

On Sun, 24 Apr 2011 23:07:52 -0400, "Barry" <none@nospam.org> wrote:


Working around chemists, I had easy access to silicone vacuum stopcock
grease. I have used it in a pinch for thermal grease and it worked well.
You can find a similar grease in the plumbing department of Lowes and
Home Depot. It is used to lubricate valve stems, rubber seals, and those
ungodly expensive ceramic Price-Pfister faucets. It will work far better
than any Permatex product as a heat transfer grease.

Oh, and one other reason to not use Permatex in this application. This
silicone is an acetoxy cure which means it releases corrosive acetic acid
when it cures.

Ahem, not any more.

Dr. Barry L. Ornitz WA4VZQ ham_call_letters at live.com


Only the very old version from thee 1960s were acetoxy cure. I had a lot
of corroded connections to learn my lesson about that. Then in the early
1970s GE came out with the thixotropic variants which use atmospheric
moisture as an initiator. No more acid release as a byproduct of cure.

And far too often, no curing, either. At least the acetic-acid-releasing
stuff got hard in a reasonable amount of time.

Isaac