Digest for sci.electronics.repair@googlegroups.com - 25 updates in 4 topics

John-Del <ohger1s@gmail.com>: Apr 12 10:27AM -0700

On Thursday, April 12, 2018 at 12:48:04 PM UTC-4, Terry Schwartz wrote:
 
> > One of the important features of those testers is that they provide a load to the circuit under test, something the LED won't be able to provide.
 
> That too can be addressed with an appropriate resistor across the entire circuit.
 
Yes, but now it's getting absurd. We're up to two LEDs (to counteract polarity, a current limiting resistor, and now a load resistor.
 
In the meantime, Oldfart could run to Harbor Freight and buy this for U.S. $3.99:
 
https://www.harborfreight.com/circuit-tester-30779.html
 
If he pays attention to the Sunday circulars and can work a scissors (or tear paper reasonably well), he can get an LED flashlight, moving blanket, tarp, or DMM *free* with *any* purchase if he brings in a coupon.
Terry Schwartz <tschw10117@aol.com>: Apr 12 10:33AM -0700

Agreed. I was just pointing out solutions.
 
Oldfart is going to do whatever he wants anyways. Probably something else absurd.
 
As long as the solution doesn't involve China. Unless that's convenient.
gregz <zekor@comcast.net>: Apr 13 07:10AM


> If he pays attention to the Sunday circulars and can work a scissors (or
> tear paper reasonably well), he can get an LED flashlight, moving
> blanket, tarp, or DMM *free* with *any* purchase if he brings in a coupon.
 
I guess that depends on distance traveled.
 
Greg
oldschool@tubes.com: Apr 13 03:37AM -0500

On Thu, 12 Apr 2018 14:11:40 +0100, Richard Jones
>Car battery charged is nominally 13.8V, take 2V off for the led = 11.8.
>Run the led at say 10mA then it's 11.8/0.010 = 1180 Ohms. An easy to
>find 1k resistor will do nicely.
 
Thanks, 1K sounds like a winner. And I will likely use a green one too.
oldschool@tubes.com: Apr 13 03:41AM -0500

On Thu, 12 Apr 2018 08:19:04 -0700 (PDT), Terry Schwartz
 
>That can easily be addressed by using two LEDs in parallel, in opposite polarity.
 
>> At the risk of pointing out the obvious, an incandescent bulb doesn't care which
>> end is positive. An LED on the other hand..................
 
Although this tester is shaped like a pen with a needle point (made to
puncture wire insulation) and a wire with a clip on the end. I normally
use the wire as the ground (to any metal part of the car body). But I do
like the idea of putting two LEDs reversed polarity in there. Easy
enough to do...
oldschool@tubes.com: Apr 13 03:51AM -0500

On Thu, 12 Apr 2018 09:48:01 -0700 (PDT), Terry Schwartz
 
>> One of the important features of those testers is that they provide a load to the
>>circuit under test, something the LED won't be able to provide.
 
>That too can be addressed with an appropriate resistor across the entire circuit.
 
Why would I need a load? This is not to test the car battery, it's just
used to check for live wires under the dash or on fuses. I mostly use it
when there is something like the heater blower wont run, or the radio is
dead, or head or tail lights not working. Trailer light wiring... Stuff
like that. My multimeter works for that too, but when I'm under the dash
it's a lot easier to see the tester light up, than to have to look at a
meter. Plus the wire puncture point on them testers is handy.
 
I should mention that the bulbs in those testers never seem to last very
long. I bet changing to a LED will last me the rest of my life.
Tim R <timothy42b@aol.com>: Apr 13 05:15AM -0700

On Friday, April 13, 2018 at 4:43:18 AM UTC-4, olds...@tubes.com wrote:
But I do
> like the idea of putting two LEDs reversed polarity in there. Easy
> enough to do...
 
Now I'll ask what is certain to be a dumb question. But maybe I'll learn something.
 
If we have two LEDs in parallel in reversed polarity, and we put 12 volts across them, aren't we exceeding both Vf and Vr? will they share the current, at some calculable ratio?
 
Sorry for my ignorance, that electrical circuits class was in the 80s.
Jeff Liebermann <jeffl@cruzio.com>: Apr 12 09:54AM -0700


>I thought I'd post this to see if anyone has used this for
>semiconductors on heat sink, grease, or is there some reason NOT to use
>this stuff for that purpose?
 
The best way to use thermal goo is to have the heat sink and device
touch each other with direct metal to metal contact, and with whatever
thermal goo you select filling in only the gaps. Making a thermal
sandwich with a thick layer of thermal goo which prevents direct
contact doesn't work very well. Idea is to grind flat and mirror
polish the heat sink and whatever is getting hot to get more metal to
metal contact, and use very little thermal goo. Some CPU's and video
chips have a mirror finish.
 
However, if you want to roll your own, diamonds are your best friend.
Here's a list of thermal conductivity of various compounds and
concoctions.
W/m*K
Diamond 1000
h-BN 600 (boron nitride)
c-BN 740 (boron nitride)
Silver 406
Copper 385
Gold 314
AlN 285 (aluminum nitride ceramic)
Aluminum 205
Graphite 200
Carbon 150
SiC 120 (silicon carbide)
Brass 109
ZnO 50 (zinc oxide)
Al2O3 25 (aluminum oxide ceramic)
TiO2 10 (titanium dioxide)
 
The common white thermal grease is zinc oxide, aluminum oxide, or
both. The expensive stuff adds boron nitride. The clear stuff is
just the grease, which is totally useless for thermal conduction but
might be a handy carrier if you want you mix your own using various
powders.
 
Tooth paste is the most common "alternative" thermal goo, although sun
screen which contains zinc oxide and perhaps titanium oxide should
also work.
 
If you can used and control a conductive thermal goo, try "liquid
metal", and alloy of bismuth and indium:
<https://www.gamersnexus.net/guides/3064-intels-thermal-problem-pt1-liquid-metal-vs-thermal-paste-benchmarks-7900x>
<http://www.thermal-grizzly.com/en/products/26-conductonaut-en>
 
Good luck.
 
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Jeff Liebermann <jeffl@cruzio.com>: Apr 12 10:16AM -0700


>I like Dow 340.
 
I have several tubes of the stuff. It works, but I prefer Arctic
Silver 5 for CPU overclocking and RF power devices. Actually, I
prefer lapping and polishing the device and heatsink, but that's not
always an option. A small tube of Arctic Silver 5 lasts me about 20
i7 size CPU's or about $0.25/per CPU because I use very little.
 
>near or between the mounting screw(s) and tighten to squeeze out
>the excess. Spreading it can cause air pockets which defeats the
>purpose. This method prevents that.
 
That's not very compatible with my dictum "The less thermal goo you
use, the better it works". You want metal to metal as much as
possible with the thermal goo just filling in the cracks and gouges.
 
>can make me case and it is hard to argue against. Anyone wants
>to dispute it make your case and then my case will bury you.
>Guaranteed.
 
I've posted my test results in sci.electronics.design. I'll see if I
can find the article. You might find it of interest.
 
>on to the heatsink by hand with as much force as possible.
>Screws strip in aluminum and some of them have a spring type
>hold down.
 
Sigh.
 
>thermal insulator but it beats air. the white stuff has microscopic
>particles in suspension and they do most of the heat conduction.
>the clear stuff doesn't have it. Don't use it.
 
At least we agree on that part.
 
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Jeff Liebermann <jeffl@cruzio.com>: Apr 12 10:31AM -0700

On Thu, 12 Apr 2018 10:16:55 -0700, Jeff Liebermann <jeffl@cruzio.com>
wrote:
 
>I've posted my test results in sci.electronics.design. I'll see if I
>can find the article. You might find it of interest.
 
This should work:
<https://groups.google.com/d/msg/sci.electronics.design/s_TJxYnypVk/1oSFPQdCBwAJ>
 
A bit on tooth paste:
<https://groups.google.com/d/msg/sci.electronics.design/s_TJxYnypVk/545qJWVLBwAJ>
 
Using gold leaf:
<https://groups.google.com/d/msg/sci.electronics.design/s_TJxYnypVk/yCgpwwtQBwAJ>
 
Plenty more in that thread:
 
I found a more complete list of thermal conductivity:
 
W/m*K
Diamond 1000
c-BN 740 (Cubic Boron Nitride)
h-BN 600 (Hexagonal Boron Nitride)
Silver 406
Copper 385
Gold 314
AlN 285 (aluminum nitride ceramic)
Aluminum 205
Graphite 200
Carbon 150
SiC 120
Brass 109
Indium 86
ZnO 50 (zinc oxide)
Al2O3 25 (aluminum oxide ceramic)
Pastes 4.0
SilPad 2000 3.5
Circuit Works 1.84
Dow Corning 340 0.67
 
Note that most white thermal goo at the low end of the thermal
conductivity list with Dow Corning 340 in the really awful category.
Don't believe me? See:
<http://www4.dowcorning.com/applications/search/products/details.aspx?prod=01015443&type=PROD>
and look in the box under "properties".
Thermal Conductivity = 0.67 Watts per meter K
 
 
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
etpm@whidbey.com: Apr 12 11:59AM -0700

On Thu, 12 Apr 2018 10:31:09 -0700, Jeff Liebermann <jeffl@cruzio.com>
wrote:
 
><http://www4.dowcorning.com/applications/search/products/details.aspx?prod=01015443&type=PROD>
>and look in the box under "properties".
> Thermal Conductivity = 0.67 Watts per meter K
I use some very fine particle size diamond lapping compounds in my
shop. Maybe I should consider using some for heat sink compound next
time I want to overclock the crap out of something. In fact, it could
first be used for lapping the parts and then just left in place.
Eric
John-Del <ohger1s@gmail.com>: Apr 12 12:05PM -0700

On Thursday, April 12, 2018 at 1:17:00 PM UTC-4, Jeff Liebermann wrote:
 
> >Screws strip in aluminum and some of them have a spring type
> >hold down.
 
> Sigh.
 
Not sure where you disagree Jeff. Not speaking for the other Jeff (jurb), but I agree with him. If you get too much compound out of the sides, you've wasted it. If none appears you may not have put enough.
 
The idea is to squeeze as much out as is possible ensuring that only enough to fill gaps is left, on that we all agree. Forcing the device down by external pressure helps make sure any excess is forced out without relying on the devices own hardware to accomplish.
 
The center daub verses the even spread is debatable either way. RCA back in the late 60s told us to use the center daub and let it spread out on it's own. Their reason was to avoid air pockets. On small devices like transistors, that's what I do. On larger devices, I don't think enough pressure can be exerted to ensure a large area can force enough compound out of the joint, so I tend to carefully spread as thin a layer as I can accomplish.
Jeff Liebermann <jeffl@cruzio.com>: Apr 12 01:31PM -0700


>I use some very fine particle size diamond lapping compounds in my
>shop.
 
What's the grain diameter? If it's larger than the depth of the
cracks and crevasses in the aluminum extruded heat sink, then you're
taking a step backwards. The bulk of the heat is passed by metal to
metal contact.
 
>Maybe I should consider using some for heat sink compound next
>time I want to overclock the crap out of something. In fact, it could
>first be used for lapping the parts and then just left in place.
 
As I vaguely recall, the typical flatness specs for extruded heat
sinks is something like 0.007 in/in. So, if the heat sink is 2 inches
wide, it can be warped 0.014" and still be considered usable. Ugh. It
will take an awfully large amount of heat sink goo to fill a 0.014"
gap.
 
The lack of flatness also causes problems when one tries to using such
a heat sink as a lapping plate. If the CPU can is softer than the
aluminum, it will convert the formerly flat can into a warped version
of the not very flat heat sink. I did stuff like this in the distant
past and found a really flat lapping plat to be a necessity.
 
If you want to see how bad it can get, take a black felt tip pen and
"paint" the top of the CPU or the heatsink black. Find a flat surface
(glass is good). Drop a sheet of fine emery cloth (2000 grit) on the
flat plate. Move the heat sink very slightly over the sand paper.
Inspect the heatsink. Where the heat sink was raised, the sandpaper
will remove the ink. Where there was a depression, the paint will
remain in place. Extra credit for repeating the test with a hot or
cold heat sink. Thermal expansion in an extrusion isn't uniform and
you will see bending in the heatsink.
 
There's also a problem with diamond dust and grease. While the grease
is great of keeping the diamond dust in place and making it easy to
apply, thermal cycling tends to pump the grease away from hot spots
leaving rather voids. You can sometimes see this when disassembling a
CPU and heatsink combination that has been running for a few years. If
you take it apart immediately after assembly, the thermal goo is
uniformly distributed (as long as the heat sink is reasonably flat).
However a few hundred thermal cycles later, it will have voids.
 
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Jeff Liebermann <jeffl@cruzio.com>: Apr 12 08:05PM -0700

On Thu, 12 Apr 2018 12:05:53 -0700 (PDT), John-Del <ohger1s@gmail.com>
wrote:
 
>> >hold down.
 
>> Sigh.
 
>Not sure where you disagree Jeff.
 
Sigh 2.0
 
>Not speaking for the other Jeff (jurb), but I agree with him.
 
That makes three Jeff's. Nobody ever agrees with me, so you must be
referring to Jeff 1.0.
 
>devices, I don't think enough pressure can be exerted to ensure
>a large area can force enough compound out of the joint, so
>I tend to carefully spread as thin a layer as I can accomplish.
 
As usual, I beg to differ:
 
1. If you apply enough pressure to make the thermal goo ooooze out
from the sandwich, you will either bend the device (as in a TO-3 or RF
power xsistor) or simply not be able to apply enough pressure with the
mounting screws and springs. I was going to calculate or measure the
pressure applied based on the recommended mounting screw torque for
various heat sinks, but don't have the time. I might have some time
this weekend to sandwich some Dow Corning 340 between two metal slabs
in an arbor press with a load cell and see what it really takes to
squeeze out the thermal goo. As you mention, I also suspect it will
be rather high pressure, far beyond what can be done with small
fasteners. Offhand, I would guess that this method was invented by a
thermal goo salesman in order to inspire users to consume more of his
company's thermal goo.
 
2. The problem with forming bubbles (voids) in the thermal goo was
originally mentioned in the literature in reference to removing the
heat sink after the thermal goo was applied. That will certainly
create bubbles. Somehow, someone extended that to the initial
application of thermal goo, which is not correct. I've never bothered
to prove this, so if you have time, try a blob of your favorite
thermal goo between two glass plates and look at it under a
microscope. If there are any bubbles, they should be obvious. If you
want, I can do this Friday as I have the necessary equipment:
<http://802.11junk.com/jeffl/pics/microscopes/Olympus%20BH/slides/Olympus%20BH.html>
3. Thermal goo is fairly cheap. However, it does make a mess when
the excess is squeezed out of the heat sink sandwich. I prefer not
cleaning up the mess.
 
My method of applying thermal go is fairly simple. Find the direction
on the heat sink in which the machining marks and gouges run. Apply a
tiny amount of thermal goo to the heat sink. Use a plastic razor
blade:
<https://www.google.com/search?q=plastic+razor+blade&tbm=isch>
to smear the thermal goo in the direction of ACROSS the machine marks.
The idea is to push the thermal goo into the grooves, crevasses, and
gouges in the heat sink. If the mating part of the sandwich also has
machine marks, do the same thing. The initial blob of thermal goo is
intentionally insufficient to cover the entire heat sink. Add small
blobs and continue to smear until the surface is covered. You will
see quite a bit of metal. That's good as you want metal to metal
contact. If there's any excess, wipe it off with the plastic razor.
When done, clamp it together and DON'T take it apart for "inspection".
If you do, start over by wiping the heat sink clean with alcohol, let
dry, and do the blob thing again. Thermal goo tends to harden as the
carrier evaporates. It will not flow into the cracks easily and will
resist compression. Best to start from scratch.
 
 
 
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Fox's Mercantile <jdangus@att.net>: Apr 12 10:34PM -0500

On 4/12/18 10:05 PM, Jeff Liebermann wrote:
> the direction on the heat sink in which the machining marks
> and gouges run. Apply a tiny amount of thermal goo to the
> heat sink. Use a plastic razor blade:
 
As the original Jeff-1.0, I have to agree with Mr. Liebermann.
 
Originally, I was in the "blob and clamp" group. But, aside
from the mess that tends to make, I learned that really was
not the right method.
 
Of course, being the lazy cunt I am, what I usually do is just
put a small blob on the part, smear it around with my fingertip
until I have a very thin layer spread over the entire part.
Then clamp it together. It may not be quite as right, but it's
a hell of a lot messy and I haven't had any overheating failures.
 
As in all things in life, there's a right way to do things, then
there's the internet, which will teach you all the other 101 ways
of doing it wrong.
 
 
--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com
jurb6006@gmail.com: Apr 13 01:37AM -0700

>"What's the grain diameter? If it's larger than the depth of the
cracks and crevasses in the aluminum extruded heat sink, then you're
taking a step backwards."
 
Now you're getting into the RMS finish left by the machines. In mass production I doubt it is very good. It is likely the grain is fine enough, in fact I have seen the results of machining on the surface and it looks like manufacturers are derating enough or just don't care.
 
>"The bulk of the heat is passed by metal to
metal contact. "
 
Which is why I apply as much pressure as possible before tightening any screws. The strip, some devices are mounted by clips and the pressure depends on its modulus of elasticity. One advantage is that over time it presses continually and closes the gap, if any.
 
There is this pink shit out there that has such a high viscosity that I consider it unacceptable. It is hard to squeeze out of the damn tube, as such it would take so much force to actually get the high spots down to metal to metal contact that it would probably damage the device.
 
I have used tools to compress these, and I know when to stop. When you tighten the vise grips or whatever a little bit more and get no more goop then it is pretty much done. In the case of a large STK IC for example, I will take the old part and put it on top of the new part so it spreads the force and isn't likely to break the case. Squeeze the whole shebang until no more comes out.
 
As far as the compound and its additives, diamond dust is probably the best. Copper beats aluminum or zinc oxide, but diamond blows their doors off. It also has a very good dielectric strength except for blue diamond. Apparently whatever "impurity" is in there causes it. I don' t feel like looking up what that is, feldspar or some shit ? Doesn't matter. Diamond does have a cost though, just how much is that semiconductor worth ?
 
>"The lack of flatness also causes problems when one tries to using such a heat sink as a lapping plate. "
 
I wouldn't do that with a computer CPU. I have done it a few times with other devices and that was only so mush, I did not really remove any significant material. Truth is I was low on the "birdshit" so I thinned it out a bit. Beats nothing and the guy didn't want to wait.
 
Actually I have cleaned a bunch of them with coffee filters. They do remove some metal. In fact the did it to VCR heads as well, seeing that black on it was not dirt, it was aluminum. It is time to stop, but the heads were about as clean as they'll ever get, and it may have enhanced head to tape contact a bit. Just don't take off too much or there will be a bunch of wear and there goes your gap and azimuth offset sooner.
 
>"If you want to see how bad it can get, take a black felt tip pen and "paint" the top of the CPU or the heatsink black. Find a flat surface (glass is good). Drop a sheet of fine emery cloth (2000 grit) on the flat plate. "
 
Actually the coffee filter should work.
 
That sounds like scraping. you know you have machines, and the ways are straight. Well those are cut on machine with straight ways so they are straight. And the ways for that machine are cut on a... this could go on forever. What is the FIRST reference ?
 
Scraped on plates. People actually scrape them by hand. they have a special surface on which the high spots are perfectly flat to withing a millionth of an inch, but there are valleys for oil. A roller will roll perfectly straight, or any guide that does not damage the plate. How to achieve this ?
 
They take two plates that are somewhat flat and blue them and put them together, where the bluing is not is a high spot so they take that down with the scraping tool. The two plates eventually seem flat, but they might not be. One could be perfectly concave and the other convex to the exact same degree so they mate, but are not straight. So they have to use a third plate. you can't have a concave and a convex plate math another plate, it is simply impossible. And with hand tools they get them within millionths of an inch. I have watched them, and watched them sell them. Most companies do not need that accuracy but some do. they cannot tolerate a copy of a copy of a copy of a copy of flatness, they want the original. My friend makes the originals.
 
This is more accurate than polishing granite plates or even countertops. usually those are done with optical flats and/or light at an oblique angle, along with a good eye. I got a few sample from my late friend who did those granite and marble tops at his day job, other times he was a sculptor. I commissioned him to do one but he died so it is not done. i use those samples to process food, meat usually because we buy in bulk. not easy lugging a piece into the kitchen but it is worth the trouble, and I like to use on the occasions when I make a real pizza. All the pizza places around here just get worse and worse. They mostly suck or charge an arm and a leg.
 
>"thermal cycling tends to pump the grease away from hot spots
leaving rather voids"
 
Hopefully those voids are where metal to metal contact was actually achieved. They are usually under spring pressure.
 
>"Thermal expansion in an extrusion isn't uniform and
you will see bending in the heatsink. "
 
Mass production. I am surprised things work as well as they do. but all the mid fi audio amps are junk. Of course they want things to last two days past the warranty. One day is pushing it a bit too much.
oldschool@tubes.com: Apr 13 04:10AM -0500

On Thu, 12 Apr 2018 13:31:11 -0700, Jeff Liebermann <jeffl@cruzio.com>
wrote:
 
>cracks and crevasses in the aluminum extruded heat sink, then you're
>taking a step backwards. The bulk of the heat is passed by metal to
>metal contact.
 
For power transistors, there is no metal to metal contact at all, if
there is a mica insulator in between the transistor and the heat sink.
Somehow that thermal paste transfers the heat thru that mica.
 
Going way back, I think my first encounter with power transistors were
the audio power output transistor in car radios. I remember working on
one and got that grease on my hands and I had to ask the teacher what
that was. He handed me a tube of it and told me to make sure the mica is
not cracked and make sure to apply enough of that grease so it oozes out
when I tighten the screws. Then he explained the purpose of it. That was
in the 1960s.
 
Since then, I've probably used more on CPUs than I ever did on
transistors. But the CPUs dont have an insulator on between.
oldschool@tubes.com: Apr 13 04:18AM -0500

>Knowing how marginal some automotive cooling systems are, I'd plump for
>the 60% mix personally, even if there are other benefits to using 100%.
 
>This was a few years back though, maybe newer coolants behave differently?
 
I dont know how this got into discussing Antifreeze, but you are
supposed to mix it 50-50. They claim that 100% antifreeze can freeze.
(Personally I have never seen it freeze). But I usually mix around 60%
AF and 40% water. I dont buy that premixed AF. The price is usually
about the same per gallon, so you're paying for water. That stuff is
made for people who are too lazy or stupid to mix it themselves...
jurb6006@gmail.com: Apr 13 04:56AM -0700

>"I dont know how this got into discussing Antifreeze,"
 
I mentioned it, but that was in another thread.
 
>"but you are supposed to mix it 50-50. They claim that 100% antifreeze can freeze."
 
Whoever claimed that is an idiot. Don't listen to them. Actually anytihng can freeze, but that is not what they meant. The statement indicates they're totally unfamiliar with chemistry and physics.
 
>"(Personally I have never seen it freeze). But I usually mix around 60% AF and 40% water. I dont buy that premixed AF. The price is usually about the same per gallon, so you're paying for water. That stuff is made for people who are too lazy or stupid to mix it themselves... "
 
It used to be that sex sells, now it is easy sells. This country and half the world is into easy, the easy way out. It has its costs.
 
As for antifreeze, if there is no water at all in there it is much less likely to form corrosive components. There is a difference in how it cools though, thus :
 
At the cylinder walls the heat gets intense enough to boil the antifreeze mixture and there will be a vapor pocket in between the coolant and the heat. It does cool by evaporation some, but that also decomposes the ethylene glycol to some extent.
 
Though water has better thermal conductivity than ethylene glycol, that is offset by the higher boiling point which means that more of the coolant will be in contact with the heat. Conduction of the heat causes more even cooling than evaporation.
 
Also, the overall pressure in the cooling system is lower, resulting in less stress on all the sealing components as well as the hoses.
 
Since I started using pure antifreeze with no water I have never had a cooling system problem. Periodic flushes are unnecessary, look at it years later and it is still green, it never turns brown. It will never freeze in any environment in which you can survive, about 8.9F. It does not boil until 387F, much higher than water, which is what makes it cool better.
 
There is a car maker that uses pure polypropylene glycol as coolant in some models, don't recall which. It is highly hydrophilic so it is in a sealed system with no overflow or return. It boils at 381F and freezes at -74F. Another uses oil, though I am pretty sure it is not regular engine oil. the thermal conductivity is low so while it would not boil much, it would not remove as much heat and the localized pockets of it hot would probably cause breakdown. It may be a synthetic, I am not sure right now.
 
Another thing abut the lazy consumer, soem of them don't even read. First of all if they read the ingredients of the shit they buy to eat they wouldn't. But I think stores put the mixed coolant right with the pure antifreeze and people who don't pay attentyion just buy it because they see a slightly lower price. Lkke im a grocery store, you got "tastes like BUTTER", "can't beleive it's not BUTTER". Even paint, want oil based primer ? Look at the label carefully, many of them say "for OIL BASE", "to be used with OIL BASE" etc.
 
The money game. It keeps the stupidity contest on and people are winning all the time.
Jeff Liebermann <jeffl@cruzio.com>: Apr 12 10:53AM -0700

On Thu, 12 Apr 2018 09:31:50 -0700 (PDT), John-Del <ohger1s@gmail.com>
wrote:
 
>I've heard of Jeff - never heard of you. From what I've read
>so far, you will never know a tenth of what Jeff does (and
>I suspect I'm being generous). Further, he's not "snit"..
 
Cool. My favorite subject... me. I'm honored.
Oh wait. Which Jeff?
 
 
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Fox's Mercantile <jdangus@att.net>: Apr 11 09:55PM -0500

On 4/11/18 9:23 PM, Ragnusen Ultred wrote:
> Apple.
 
Yup. Called it. It's another one of your anti-Apple rants.
 
Come tomorrow, I'll still be not Snit, and you'll still be
a useless troll.
 
And I've never felt the need to hide behind constantly changing
names.
 
Twelve years ago, I was an expert witness testifying against
Motorola in Federal court.
Their plan was to claim that any third party repairs were
counterfeiting.
Fortunately for everyone involved, with the exception of Motorola
and their lawyers, that fell through due to my testimony.
 
<https://www.manatt.com/>
Harold Pick, Et. Al. vs Motorola
Despite having 375 lawyers, Motorola couldn't make their case.
They lost.
 
 
 
--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com
John-Del <ohger1s@gmail.com>: Apr 12 12:08PM -0700

On Thursday, April 12, 2018 at 1:53:37 PM UTC-4, Jeff Liebermann wrote:
> >I suspect I'm being generous). Further, he's not "snit"..
 
> Cool. My favorite subject... me. I'm honored.
> Oh wait. Which Jeff?
 
The good looking one of course!!!!
Fox's Mercantile <jdangus@att.net>: Apr 12 10:16AM -0500

On 4/12/18 6:56 AM, Ragnusen Ultred wrote:
> hehhehheh ... no way...
 
Yeah, I know, sucks to be you huh?
Sitting alone in a room surrounded by sticky Kleenex tissues
as you bleat endlessly about shit you don't understand.
 
 
--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com
Jon Elson <jmelson@wustl.edu>: Apr 12 05:52PM -0500

N_Cook wrote:
 
> Stretch over the active face of each cart with a drop of
> meths/denatured-alcahol in each balloon and store on a ledge with
> balloons dangling.
The ONLY way to avoid bloced jet nozzles is to TOTALLY AVOID inkjet
printers. I CURSE the things! I curse my stupidity in rescuing some of
them from the trash at work and trying to make them work.
 
We had some at work, and every Monday morning I had to fiddle with them to
get them unblocked. Just 2 days idle during the weekend and they were in
trouble.
 
Give me a laser printer, please! (Wax jet is the 2nd choice, but the ink is
expensive.)
 
Jon
N_Cook <diverse@tcp.co.uk>: Apr 13 08:38AM +0100

On 12/04/2018 23:52, Jon Elson wrote:
 
> Give me a laser printer, please! (Wax jet is the 2nd choice, but the ink is
> expensive.)
 
> Jon
 
I was watching the latest David Attenborough natural history series and
nature got there first. Apparently the mottled colouration on bird eggs
is due to an inkjet printer like process. The caulm containg yolk and
albumen is rotated in a chamber with multiple ducts that eject a
different colour calcium based chemical formulation at different times
building up the patterning, clever stuff. Millions of years before
Epson,Canon, HP etc
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