Repaired Harbor Freight digital caliper

On Nov 20, 8:45 pm, Jeff Liebermann <je...@cruzio.com> wrote:

On Sun, 20 Nov 2011 16:47:25 -0800 (PST), "Ron D." wrote:

I have a cheap Caliper too and it recently went flakey.

I did my standard trick:  Remove battery.  Short battery contacts:
Insert new battery.  Worked.

My cheap electronic caliper goes nuts when I transmit on UHF anywhere
near it.  However, it doesn't require the battery removal ordeal to
recover.  I just reset to zero and continue.

Mine uses an LR44 and you HAVE TO use an LR44, not a substitute
battery that you can get a Radio Shack.
Mechanically they are not the same.

I beg to differ.  The general package name is LR44 in an 11.6mm dia x
5.4mm thick package alkaline cell.  There are slight variations, but
the IEC LR1154 equivalents (LR44/LR154, A76, 157/303/357) are all the
same size.  Where you can have problems is that the SR44/SR1154 silver
oxide cells come in the same package.  They have about 50% more
capacity and a much flatter discharge curve.  Some of the cheapo
calipers crap out below about 1.4V.  The alkaline battery has plenty
of capacity left at 1.4V, but the caliper doesn't want to run.  If
your caliper cames with a silver-oxide cell, it should probably use
silver oxide batteries.  If it came with alkaline and has a short
battery life, it might be worthwhile trying silver-oxide.  If you're
ambitious, it might be useful to run the caliper off a bench power
supply and check how low a voltage will work.

I just measured a Harbor Freight (Chinese) 8-incher.

Drain: 13.5uA (off), 14.5uA (on)
Battery low threshold (blinking display): 1.37V
Lowest operating voltage: 1.01V

So, it's clearly made for silver-oxide cells. The battery low
threshold is set appropriately for a silver oxide cell (e.g. SR-44).

It's a lousy threshold for using alkalines--they're barely broken in
at that voltage.

14.5uA means a year from a silver oxide cell--that's not horrible.

--
Cheers,
James Arthur

 

On Nov 20, 7:47 pm, "Ron D." <ron.doz...@gmail.com> wrote:

I have a cheap Caliper too and it recently went flakey.

I did my standard trick:  Remove battery.  Short battery contacts:
Insert new battery.  Worked.

Mine uses an LR44 and you HAVE TO use an LR44, not a substitute
battery that you can get a Radio Shack.
Mechanically they are not the same.

You can get the silver oxide cells occasionally from Big Lots, a card
of 5 goes for something like $2.50. Other than that, drugstores have
'em for something like $3-5, per cell (!).

And yes, they're mechanically the same.

--
Cheers,
James Arthur

 

[DoN. Nichols]

On 2011-11-20, Jeff Liebermann <jeffl@cruzio.com> wrote:

On Sun, 20 Nov 2011 13:38:36 -0000, "N_Cook" <diverse@tcp.co.uk
wrote:
An engineer told me never close the jaws of a micrometer or vernier calipers
for storage, leave the jaws open slightly.

True. With gear type calipers, the lubricating grease tends to
migrate to that position. If a sufficiently filthy environment, an
lump of dirt encrusted grease will be left in that position. If it
happens to be at 0.0, then it will be difficult to accurately
calibrate the mechanism.

But he said "Vernier calipers" which have no such mechanism.
Though people tend to lock the slides, so thermal stress distortion
could be a problem with them stored closed and locked.

There are also some minor reasons, such as
the tendency for two parallel surfaces to trap moisture between them
and rust.

Assuming non stainless steel jaws. (I've never seen calipers
with carbide faced jaws, unlike good micrometers.)

[ ... ]

How do they know of any movement of
the jaws when switched off elsewise?

Only the display is turned off. The pulse counting mechanism is still
operating and functional. The downside is that the battery will be
dead in about 6-9 months. Most include a spare LR44 battery. I had
to buy a pile of them to keep my calipers going. Somehow, the battery
is usually dead when I need to use them.

50 batteries for $3.75
http://www.ebay.com/itm/220751739681

There is your problem -- cheap cells. Don't use the LR44 (those
are alkaline batteries), use the SR44 and SR357 (Silver Oxide cells,
with much longer life). Then things will probably last at least six
months in storage. The SR44 and SR357 are pretty much interchangeable.
I don't even know why there are the two series -- though you will often
find them with both designators marked on the same cell or packaging.

I have an expensive set of Starett calipers (both metric and US). I
use them more often than the electronic variety, mostly out of habit.
My most useful measuring tools are my 6" pocket steel scale and a tape
measure.

While I tend to use the digital calipers by preference. Half as
many calipers needed to cover the metric and inch measurements.

Enjoy,
DoN.

--
Remove oil spill source from e-mail
Email: <BPdnicholsBP@d-and-d.com> | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

 

On Nov 20, 9:55 pm, "Martin Riddle" <martin_...@verizon.net> wrote:

dagmargoodb...@yahoo.com> wrote in message

news:07d0ac35-1cf3-4ed1-ba85-cd32f2f6ea0b@p2g2000vbj.googlegroups.com...



On Nov 20, 8:45 pm, Jeff Liebermann <je...@cruzio.com> wrote:
On Sun, 20 Nov 2011 16:47:25 -0800 (PST), "Ron D." wrote:

I have a cheap Caliper too and it recently went flakey.

I did my standard trick:  Remove battery.  Short battery contacts:
Insert new battery.  Worked.

My cheap electronic caliper goes nuts when I transmit on UHF anywhere
near it.  However, it doesn't require the battery removal ordeal to
recover.  I just reset to zero and continue.

Mine uses an LR44 and you HAVE TO use an LR44, not a substitute
battery that you can get a Radio Shack.
Mechanically they are not the same.

I beg to differ.  The general package name is LR44 in an 11.6mm dia x
5.4mm thick package alkaline cell.  There are slight variations, but
the IEC LR1154 equivalents (LR44/LR154, A76, 157/303/357) are all the
same size.  Where you can have problems is that the SR44/SR1154
silver
oxide cells come in the same package.  They have about 50% more
capacity and a much flatter discharge curve.  Some of the cheapo
calipers crap out below about 1.4V.  The alkaline battery has plenty
of capacity left at 1.4V, but the caliper doesn't want to run.  If
your caliper cames with a silver-oxide cell, it should probably use
silver oxide batteries.  If it came with alkaline and has a short
battery life, it might be worthwhile trying silver-oxide.  If you're
ambitious, it might be useful to run the caliper off a bench power
supply and check how low a voltage will work.

I just measured a Harbor Freight (Chinese) 8-incher.

Drain: 13.5uA (off), 14.5uA (on)
Battery low threshold (blinking display): 1.37V
Lowest operating voltage: 1.01V

So, it's clearly made for silver-oxide cells.  The battery low
threshold is set appropriately for a silver oxide cell (e.g. SR-44).

It's a lousy threshold for using alkalines--they're barely broken in
at that voltage.

14.5uA means a year from a silver oxide cell--that's not horrible.


Why bother including an on off switch?

It's really not worth it for 1uA.

If I designed these, I'd shoot for 2uA active draw, like the
Mitutoyos, and set the battery low threshold at 1.1V (for alkalines).
The battery consumption is the biggest fault with these. Apart from
that, they're impressive.

I sometimes think about wiring up a "AAA" or solar cell and just
forgetting it, but for $0.50 a year it's not worth the trouble.

--
Cheers,
James Arthur

 

[DoN. Nichols]

I've ignored the "Followup-To: " header, because I believe that this
also belongs in at least rec.crafts.metalworking, where I am following
it, and I would miss my own followup and any responses if it were kept
to a single group as requested.

On 2011-11-20, Fred Abse <excretatauris@invalid.invalid> wrote:

On Sun, 20 Nov 2011 06:41:03 -0600, amdx wrote:

That's why I like the Dial calipers vs Digital Calipers, no concern
about batteries or electronics.

I prefer a "proper" vernier. At least you can verify those by eye.

Depends on how old the eye is and how good the illumination is.

I never
did trust digital calipers to hold their zero and not skip under workshop
conditions, Half a lifetime dealing with incremental encoders has made me
wary.

The old B&S ones, which used glass encoders in the slot where
the rack gear would otherwise be were sensitive to coolant in the slot.
But the modern units seem to be quite good at not skipping.

I *might* trust a Mitutoyo digital caliper or height gage in inspection
room conditions.

I trust them (as much as a caliper *can* be trusted compared to
a micrometer) in shop conditions as well.

Dial calipers have all sorts of racks and gears to go sloppy.

Agreed -- or to pick up bits of swarf and skip.

I suppose nobody under fifty knows how to read a real vernier, or a slide
rule for that matter ;-(

I know how to use both -- but then I am (well) over fifty.

But there have been verniers on the thimbles of the better
micrometers much more recently than that, so presumably some of the
younger crowd know.

Enjoy,
DoN.

--
Remove oil spill source from e-mail
Email: <BPdnicholsBP@d-and-d.com> | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

 

[gregz]

Jeff Liebermann <jeffl@cruzio.com> wrote:

On Sun, 20 Nov 2011 23:47:58 +0000 (UTC), gregz <zekor@comcast.net
wrote:

Jeff Liebermann <jeffl@cruzio.com> wrote:
On Sat, 19 Nov 2011 22:19:11 -0600, Jim Yanik <jyanik@abuse.gov
wrote:

I wonder if Cramolin/DeOxit would work on the conductive strip?

http://siber-sonic.com/electronics/caig.html
Sorta. The original Cramolin contained about 5% oleic acid, which is
great for removing surface oxidation, but is also mildly corrosive to
copper. The current version is DeOxit from Caig Labs. It comes in an
amazing variety of forms, and is allegedly non-corrosive.
http://store.caig.com/s.nl/sc.2/.f
The MSDS data shows the active ingredients as a "trade secret". Oh
well.

I never have been able to get much visible effect of so called corrosion
removers. Oleic acid probably being best, but supposedly the cramolin
chemist also had input on making deoxit. On a short term test I can visibly
wipe off oxide with an alcohol swipe, being just as effective. Most of the
removing is mechanical in nature, and any liquid helps.

The oleic acid is only about 5% of the contact cleaner. Over a period
of time, it will help remove any oxide deposits. However, at such a
low concentration, it should not be expected to dissolve a substantial
oxide accumulation. Basically, any detergent will do as well if you
can live with the residue.

More on Cramolin:
http://www.pitt.edu/~szekeres/caigcram.htm
http://siber-sonic.com/electronics/caig.html

Cleaning brass clocks. Note the section on oleic acid.
http://www.abbeyclock.com/brass2.html
The oleic acid therefore has two functions: to remove
the oxide layer from the metals and to act as a soap
to remove the dirt and oils. The cleaning solution
has about 90% ammonia solution with about 5% oleic
acid and 5% acetone added, thereby leaving plenty
of excess ammonia molecules to keep the solution
alkaline.
The acetone is to accelerate evaporation. Oleic acid also has the
advantage of being common, cheap, and non-toxic. It's a by product of
corn and veggie oil production.

http://www.dialcover.com/components.html
Scroll down to "Cease and Desist" contact cleaner. Much the same as
my home made formula except I won't use acetone because it eats
plastic. Ordinary isopropyl alcohol is safer.

Homebrew cleaners and protectors:
http://www.pitt.edu/~szekeres/cleaner.htm
The comments on the effects of silicones plus salt in WD40 are
interesting.

Yes, some old navy guy contacted me and I stuck it in there. Have not
updated anything for a while.

Greg szekeres

 

[gregz]

gregz <zekor@comcast.net> wrote:

Jeff Liebermann <jeffl@cruzio.com> wrote:
On Sun, 20 Nov 2011 23:47:58 +0000 (UTC), gregz <zekor@comcast.net
wrote:

Jeff Liebermann <jeffl@cruzio.com> wrote:
On Sat, 19 Nov 2011 22:19:11 -0600, Jim Yanik <jyanik@abuse.gov
wrote:

I wonder if Cramolin/DeOxit would work on the conductive strip?

http://siber-sonic.com/electronics/caig.html
Sorta. The original Cramolin contained about 5% oleic acid, which is
great for removing surface oxidation, but is also mildly corrosive to
copper. The current version is DeOxit from Caig Labs. It comes in an
amazing variety of forms, and is allegedly non-corrosive.
http://store.caig.com/s.nl/sc.2/.f
The MSDS data shows the active ingredients as a "trade secret". Oh
well.

I never have been able to get much visible effect of so called corrosion
removers. Oleic acid probably being best, but supposedly the cramolin
chemist also had input on making deoxit. On a short term test I can visibly
wipe off oxide with an alcohol swipe, being just as effective. Most of the
removing is mechanical in nature, and any liquid helps.

The oleic acid is only about 5% of the contact cleaner. Over a period
of time, it will help remove any oxide deposits. However, at such a
low concentration, it should not be expected to dissolve a substantial
oxide accumulation. Basically, any detergent will do as well if you
can live with the residue.

More on Cramolin:
http://www.pitt.edu/~szekeres/caigcram.htm
http://siber-sonic.com/electronics/caig.html

Cleaning brass clocks. Note the section on oleic acid.
http://www.abbeyclock.com/brass2.html
The oleic acid therefore has two functions: to remove
the oxide layer from the metals and to act as a soap
to remove the dirt and oils. The cleaning solution
has about 90% ammonia solution with about 5% oleic
acid and 5% acetone added, thereby leaving plenty
of excess ammonia molecules to keep the solution
alkaline.
The acetone is to accelerate evaporation. Oleic acid also has the
advantage of being common, cheap, and non-toxic. It's a by product of
corn and veggie oil production.

http://www.dialcover.com/components.html
Scroll down to "Cease and Desist" contact cleaner. Much the same as
my home made formula except I won't use acetone because it eats
plastic. Ordinary isopropyl alcohol is safer.

Homebrew cleaners and protectors:
http://www.pitt.edu/~szekeres/cleaner.htm
The comments on the effects of silicones plus salt in WD40 are
interesting.

Yes, some old navy guy contacted me and I stuck it in there. Have not
updated anything for a while.

Greg szekeres

I bought some oleic acid from bill. I tried diluting it with isopropyl
alcohol, seems to mix well.

My old cans of spray of Contaclean got all sticky and the metal was looking
bad where it contacted the fluid build up. I think it also gummed up pots.
Contaclean is Cramolins replacement for cramolin. I'm not trying to order
it anymore because it costs watt too much to ship into the states.
Interesting though, my old vial of cramolin never gummed up on the injector
tube. The can of Contaclean clearly states to remove before operating, with
a cleaner. Gummy!!
I can't remember if I dried pure oleic acid to test for gumminess. Probably
does.
Deoxit does not gum. Never tried to dry up pure red caig in the vial
injector.
Deoxit is only 5% concentration in the spray.

Greg

 

[Jeff Liebermann]

On Mon, 21 Nov 2011 03:33:20 +0000 (UTC), gregz <zekor@comcast.net>
wrote:

Jeff Liebermann <jeffl@cruzio.com> wrote:
Homebrew cleaners and protectors:
http://www.pitt.edu/~szekeres/cleaner.htm
The comments on the effects of silicones plus salt in WD40 are
interesting.

Yes, some old navy guy contacted me and I stuck it in there. Have not
updated anything for a while.

Greg szekeres

Oh, those are your pages. Nice info and thanks.

The silicone and salt atmosphere problem is real. It forms sodium
silicate, which is water soluable. Add almost any acid, and you get
silicic acid. Heat and dry that you get silica gel, which is quite
hard and not very soluable in anything. It takes a while, but it does
happen.

I used to work for a marine radio manufactory in the 1970's. Customers
would sometimes use various lubricants loaded with silicone to clean
pots and switches. It would work, but about a year later, we would
get the radios back with seriously intermittent pots and switches. No
amount of solvent cleaning would fix them, so we just replaced them.
We just assumed they were internally corroded or salt encrusted. I
didn't discover the silicone and salt atmosphere problem until many
years later (when I repeated the mistake on a consulting project).

--
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]

On Mon, 21 Nov 2011 03:57:48 +0000 (UTC), gregz <zekor@comcast.net>
wrote:

I bought some oleic acid from bill. I tried diluting it with isopropyl
alcohol, seems to mix well.

Olive oil works almost as well. It's about 50% oleic acid. My
solution is mostly Coleman fuel (naphtha), some olive oil, and a
little alcohol. It works and leaves the radio smelling "organic".

My old cans of spray of Contaclean got all sticky and the metal was looking
bad where it contacted the fluid build up. I think it also gummed up pots.

Well yes. Such cleaners (and Cramolin) are mostly mineral oil. Remove
the volatiles and antioxidants, and what's left is mineral oil. There
are different types of mineral oils: paraffin, naphtha, various
petroleum distillates, and mixtures. The paraffin residue left after
evaporation might be the gum that you're seeing.

Contaclean is Cramolins replacement for cramolin. I'm not trying to order
it anymore because it costs watt too much to ship into the states.

It appears that Contaclean is the same as the old Cramolin Red
(R-100). Mostly mineral oil (hexane) and isopropyl alcohol. MSDS:
<http://www.farnell.com/datasheets/1493224.pdf>
Hmmm... looks like the oleic acid was removed.

Interesting though, my old vial of cramolin never gummed up on the injector
tube. The can of Contaclean clearly states to remove before operating, with
a cleaner. Gummy!!
I can't remember if I dried pure oleic acid to test for gumminess. Probably
does.

I would blame the mineral oil instead, especially since there doesn't
seem to be any oleic acid in the Contaclean reformulation. Oleic acid
is much like corn oil or olive oil. It will leave a gummy residue
under the correct conditions. However, there is only 5% oleic acid in
the bottle, which isn't enough to leave much residue. If there's
plenty of residue, it's probably the mineral oil.

Deoxit does not gum. Never tried to dry up pure red caig in the vial
injector.
Deoxit is only 5% concentration in the spray.

Greg
--

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]

On Sun, 20 Nov 2011 22:41:49 -0800, Jeff Liebermann <jeffl@cruzio.com>
wrote:

It appears that Contaclean is the same as the old Cramolin Red
(R-100). Mostly mineral oil (hexane) and isopropyl alcohol. MSDS:
http://www.farnell.com/datasheets/1493224.pdf
Hmmm... looks like the oleic acid was removed.

Oops. It's still there, but well hidden. It's listed as an
"aliphatic hydrocarbon", which includes fatty acids such as oleic
acid.

--
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

 

[Gunner Asch]

On 21 Nov 2011 03:24:37 GMT, "DoN. Nichols" <BPdnicholsBP@d-and-d.com>
wrote:

On 2011-11-20, Bob Engelhardt <bobengelhardt@comcast.net> wrote:
Jamie wrote:
I have the HF digital calipers and I need to pull the battery when not
in use other wise, it'll be dead next time I need it. It seems to drain
quite fast.
...

I have one & the battery lasts quite a while (doesn't get used much).
Maybe a different model. Or a different batch. Or different spots on
the quality curve <G>.

Or different quality of battery as I just posted above.

Enjoy,
DoN.

Many 99c stores sell a flatpack of 5-10 standard 357 batteries for a
dollar.

So I use 2 batteries a year. Or even 3. Im still way ahead of the curve
when SR44s are $3 each

Gunner

One could not be a successful Leftwinger without realizing that,
in contrast to the popular conception supported by newspapers
and mothers of Leftwingers, a goodly number of Leftwingers are
not only narrow-minded and dull, but also just stupid.
Gunner Asch

 

[N_Cook]

Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> wrote in message
news:2ddjc7tt4m10a6q7k7adtaofgaem1dhrrl@4ax.com...

On Sun, 20 Nov 2011 17:45:47 -0800, the renowned Jeff Liebermann
jeffl@cruzio.com> wrote:

On Sun, 20 Nov 2011 16:47:25 -0800 (PST), "Ron D."
ron.dozier@gmail.com> wrote:

I have a cheap Caliper too and it recently went flakey.

I did my standard trick: Remove battery. Short battery contacts:
Insert new battery. Worked.

My cheap electronic caliper goes nuts when I transmit on UHF anywhere
near it. However, it doesn't require the battery removal ordeal to
recover. I just reset to zero and continue.

Mine uses an LR44 and you HAVE TO use an LR44, not a substitute
battery that you can get a Radio Shack.
Mechanically they are not the same.

I beg to differ. The general package name is LR44 in an 11.6mm dia x
5.4mm thick package alkaline cell. There are slight variations, but
the IEC LR1154 equivalents (LR44/LR154, A76, 157/303/357) are all the
same size. Where you can have problems is that the SR44/SR1154 silver
oxide cells come in the same package. They have about 50% more
capacity and a much flatter discharge curve. Some of the cheapo
calipers crap out below about 1.4V. The alkaline battery has plenty
of capacity left at 1.4V, but the caliper doesn't want to run. If
your caliper cames with a silver-oxide cell, it should probably use
silver oxide batteries. If it came with alkaline and has a short
battery life, it might be worthwhile trying silver-oxide. If you're
ambitious, it might be useful to run the caliper off a bench power
supply and check how low a voltage will work.

Be sure to check how high a voltage too, and report back. ;-)



Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers:
http://www.trexon.com
Embedded software/hardware/analog Info for designers:
http://www.speff.com

If I had one of these I'd fit onto the calipers a small solar cell and diode
to trickle charge the original battery ie not specifically rechargeable ,
and replace the lid of its casing with a glass panel and leave on a bright
position .

 

[William Sommerwerck]

I never have been able to get much visible effect of so called corrosion
removers. Oleic acid probably being best, but supposedly the Cramolin
chemist also had input on making deoxit. On a short term test I can
visibly
wipe off oxide with an alcohol swipe, being just as effective. Most of the
removing is mechanical in nature, and any liquid helps.

I'm inclined to disagree. Cramolin/DeOxit definitely work on tin- and
nickel-plated surfaces. They are not as effective on gold-plated surfaces;
ProGold does a better job. It isn't just a matter of mild abrasion; a
chemical reaction of some sort is needed.

 

[J.B. Wood]

On 11/19/2011 11:19 PM, Jim Yanik wrote:

use Boeing Boeshield T-9 to prevent the rusting of your tools.

I wonder if Cramolin/DeOxit would work on the conductive strip?

Hello, and DeoxIT is the best thing I've ever come across for cleaning
and de-oxidizing electrical contacts. It also does wonders with
scratchy volume and tone pots and it'll be long while before you have to
apply it again. Sincerely,


--
J. B. Wood e-mail: arl_123234@hotmail.com

 

[Jim Yanik]

Jeff Liebermann <jeffl@cruzio.com> wrote in
news:ff9jc7h30fqjm073j6k38tic1cj6pg51jk@4ax.com:

Homebrew cleaners and protectors:
http://www.pitt.edu/~szekeres/cleaner.htm
The comments on the effects of silicones plus salt in WD40 are
interesting.

WD-40 is mostly kerosene.

--
Jim Yanik
jyanik
at
localnet
dot com

 

[Jeff Liebermann]

On Mon, 21 Nov 2011 10:36:03 -0600, Jim Yanik <jyanik@abuse.gov>
wrote:

Jeff Liebermann <jeffl@cruzio.com> wrote in
news:ff9jc7h30fqjm073j6k38tic1cj6pg51jk@4ax.com:


Homebrew cleaners and protectors:
http://www.pitt.edu/~szekeres/cleaner.htm
The comments on the effects of silicones plus salt in WD40 are
interesting.


WD-40 is mostly kerosene.

Close. It's mostly Stoddard Solvent, also known as mineral spirits.
<http://www.snopes.com/inboxer/household/wd-40.asp>
<http://en.wikipedia.org/wiki/WD-40>
<http://en.wikipedia.org/wiki/Stoddard_solvent>
50% Stoddard solvent (i.e., mineral spirits: primarily hexane,
somewhat similar to kerosene)
25% Liquefied petroleum gas (presumably as a propellant; carbon
dioxide is now used instead to reduce WD-40's considerable
flammability)
15+% Mineral oil (light lubricating oil)
10-% Inert ingredients

Reverse engineering at its best:
<http://www.wired.com/science/discoveries/magazine/17-05/st_whatsinside>

USA MSDS sheet:
<http://www.wd40company.com/files/pdf/msds-wd494716385.pdf>

The key ingredient is a sulfactant (wetting agent), to reduce surface
tension and make it "cling" to objects and "puddle" water. My
guess(tm) the reason it took 40 trys is that they had a difficult time
finding one that would work in a solvent solution.

--
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

 

[Ron D.]

Th 357 and the LR44 ARE NOT quite the same in experience, The LR44
seems to have a slightly domed top and it seems to make a difference
in all of my products that use them. I can't find evident to support
my claim, but experience, unfortunately.

In general, the LF357's fit a little looser in the holder and the
LF44's are easier to insert.

 

[gregz]

Jeff Liebermann <jeffl@cruzio.com> wrote:

On Mon, 21 Nov 2011 10:36:03 -0600, Jim Yanik <jyanik@abuse.gov
wrote:

Jeff Liebermann <jeffl@cruzio.com> wrote in
news:ff9jc7h30fqjm073j6k38tic1cj6pg51jk@4ax.com:


Homebrew cleaners and protectors:
http://www.pitt.edu/~szekeres/cleaner.htm
The comments on the effects of silicones plus salt in WD40 are
interesting.


WD-40 is mostly kerosene.

Close. It's mostly Stoddard Solvent, also known as mineral spirits.
http://www.snopes.com/inboxer/household/wd-40.asp
http://en.wikipedia.org/wiki/WD-40
http://en.wikipedia.org/wiki/Stoddard_solvent
50% Stoddard solvent (i.e., mineral spirits: primarily hexane,
somewhat similar to kerosene)
25% Liquefied petroleum gas (presumably as a propellant; carbon
dioxide is now used instead to reduce WD-40's considerable
flammability)
15+% Mineral oil (light lubricating oil)
10-% Inert ingredients

Reverse engineering at its best:
http://www.wired.com/science/discoveries/magazine/17-05/st_whatsinside

USA MSDS sheet:
http://www.wd40company.com/files/pdf/msds-wd494716385.pdf

The key ingredient is a sulfactant (wetting agent), to reduce surface
tension and make it "cling" to objects and "puddle" water. My
guess(tm) the reason it took 40 trys is that they had a difficult time
finding one that would work in a solvent solution.

Good info. Darn, I liked to use the can as a flame thrower to kill pests
with the flammable propellant. Bags worms met their doom.

Greg

 

[P E Schoen]

"Gunner Asch" wrote in message
news:aa0kc750e2tsad3028cqpm25aer8aus1mn@4ax.com...

Many 99c stores sell a flatpack of 5-10 standard 357 batteries
for a dollar.

I'm not sure I'd trust them in something any more expensive than a
flashlight. I have seen them corrode and leak. And the only thing the 99
cent store might be willing to do is give you another pack or refund your
dollar.

So I use 2 batteries a year. Or even 3. Im still way ahead of the
curve when SR44s are $3 each

I just purchased four genuine SR44s from an eBay store, for $3, including
first class mail shipping. The same company also has larger packs for quite
a bit less.
http://stores.ebay.com/RL-batterydepot?_trksid=p4340.l2563

I also measured the current draw on my calipers, and it's about 12.5 uA
either on or off. It seems to spike a bit when turned on. (So do I

They are specified at about 175 mAhr, according to http://www.sr44.com/, so
lifetime should be about 14000 hrs or 1.5 years, but the spec is for a low
voltage of 1.3V, which is probably below the limit of the electronics in the
caliper, at least for the low battery indicator.

Here is a handy list of the various sizes with different chemistry and their
mA-hr capacities: http://en.wikipedia.org/wiki/List_of_battery_sizes

Paul
www.pstech-inc.com

 

[amdx]

Harbor Freight Has the 6" dial Caliper on sale 11/24

http://www.harborfreight.com/preview-thanksgiving.html?utm_medium=email&utm_campaign=4711a&utm_source=1003

Mikek