Bimetalic domes
N_Cook
continuous curving with temperature, these are 0.5 inch diameter and make a
definite flip from concave to convex at a specific temperature. About 1mm of
abrupt movement gives a very positive transition for the switch contacts.
Would it be possible to change the characteristic temperature by grinding
back a spot/ring/radii? on one face? which face? or would it just destroy
the action/activation force?
Steve Lusardi
Steve
"N_Cook" <div...@tcp.co.uk> wrote in message news:hd608l$u0r$1...@news.eternal-september.org...
William Sommerwerck
You might find one of the sort that used to be used in kitchen appliances,
that could be inserted in a grill, waffle maker, cookpot, etc. These have
adjustable settings, which (I assume) are varied by changing the pressure on
the sensor.
N_Cook
news:hd683k$jvj$00$1...@news.t-online.com...
According to patent
"Laser adjusted set-point of bimetallic thermal disc"
it is done at production , for precise adjustment, but no specific details
of patterns/which surface/degree of variation. I'm more interested in
adjusting otherwise useless batch made for set point of 16 degree C up to
50 or 60 degree C, with no great precision, +/- 10 deg C would be fine
William Sommerwerck
> "Laser adjusted set-point of bimetallic thermal disc"
> it is done at production , for precise adjustment, but no specific details
> of patterns/which surface/degree of variation. I'm more interested in
> adjusting otherwise useless batch made for set point of 16 degree C up to
> 50 or 60 degree C, with no great precision, +/- 10 deg C would be fine
If you could find the patent for the controller I described (it's a famous
patent, from a man who patented many devices in the 50s and 60s), it might
show how this is done.
N_Cook
news:hd6ik6$eip$1...@news.eternal-september.org...
probably a John Taylor
http://content.yudu.com/A15ex7/Apro9/resources/8.htm
but no further forward, I'll suck some and see
William Sommerwerck
> http://content.yudu.com/A15ex7/Apro9/resources/8.htm
I'm not sure. The guy I'm thinking of is American.
N_Cook
remain froststats. Surprising ping and bounce as much as six inches on
change of state, the loud ping is somewhat damped when inside the casing.
Need freezer spray to change the state of these discs (hysteresis and all
that). When back to body temp I tried grinding a spot in the centre of the
concave side, no change in set temp. Tried 4 diametrical marks on the
concave side , no change in response. Tried deeper but small 8 cuts just on
the perphery, now no ping but slowly migrates from one state to the other ,
still requiring freezer spray. I wonder how they "weld" these 2 materials
together.
Jeff Liebermann
>As used in thermal switches. Instead of in form of a bimetal strip and
>continuous curving with temperature, these are 0.5 inch diameter and make a
>definite flip from concave to convex at a specific temperature. About 1mm of
>abrupt movement gives a very positive transition for the switch contacts.
Like this?
<http://www.google.com/patents/about?id=VQ4XAAAAEBAJ&dq=5903210>
or this?
<http://www.google.com/patents/about?id=BygyAAAAEBAJ&dq=3852697>
>Would it be possible to change the characteristic temperature by grinding
>back a spot/ring/radii? on one face? which face? or would it just destroy
>the action/activation force?
I don't think so (but I'm guessing). Grinding might change the
deflection or force but probably not the transition temperature. Below
some force level, it simply will not transition. My guess(tm) is that
the transition temperature is controlled by the curvature which is
rather difficult to modify.
Note that some discs are "manual reset" or "single operation" and act
as thermal fuses.
Search Google for "bimetallic snap disk".
<http://www.cpi-nj.com/snap.htm>
<http://www.thermodisc.com>
(etc...)
I tried to find the vendor of the actual discs, which might include
design information, but couldn't find anything useful.
--
Jeff Liebermann je...@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
Have you considered fire alarm heat sensors? They use a bimetal switch
internally.
Gunner
"IMHO, some people here give Jeff far more attention than he deserves,
but obviously craves. The most appropriate response, and perhaps the
cruelest, IMO, is to simply killfile and ignore him. An alternative, if
you must, would be to post the same standard reply to his every post,
listing the manifold reasons why he ought to be ignored. Just my $0.02
worth."
Jeff Liebermann
>I wonder how they "weld" these 2 materials
>together.
Probably by electroplating one of the meterials onto the other.
Martin H. Eastburn
Simple as that.
Martin
William Wixon
"Martin H. Eastburn" <lion...@consolidated.net> wrote in message
news:mxLJm.189672$Jp1....@en-nntp-02.dc1.easynews.com...
(sorry for the digression.)
huh! yesterday i was going to ask how they make copper clad stainless steel
cookware but i thought it was too dumb and too trivial a question to ask.
couple days ago i had a copper clad stainless pan delaminate the copper
cladding and was stunned. made me wonder how they attach it in the first
place. i'm guessing some sort of furnace brazing process(?). this pan is
probably over 50 years old, i think this is one of the pans my mother got as
a wedding present in the 50's. i've seen stuff (on tv and in books) about
explosive welding but am totally assuming that's NOT how they make copper
clad cookware.
http://www.frontiernet.net/~wwixon/delamination.jpg
b.w.
Roger Shoaf
"William Wixon" <wwi...@frontiernet.net> wrote in message
news:0EMJm.3532$rE5....@newsfe08.iad...
> huh! yesterday i was going to ask how they make copper clad stainless
steel
> cookware but i thought it was too dumb and too trivial a question to ask.
> couple days ago i had a copper clad stainless pan delaminate the copper
> cladding and was stunned. made me wonder how they attach it in the first
> place. i'm guessing some sort of furnace brazing process(?). this pan is
> probably over 50 years old, i think this is one of the pans my mother got
as
> a wedding present in the 50's. i've seen stuff (on tv and in books) about
> explosive welding but am totally assuming that's NOT how they make copper
> clad cookware.
>
> http://www.frontiernet.net/~wwixon/delamination.jpg
>
That is really wild. I have never heard of these delaminating. Was there
something you did like overheat the pot or something?
--
Roger Shoaf
About the time I had mastered getting the toothpaste back in the tube, then
they come up with this striped stuff.
Roger Shoaf
> huh! yesterday i was going to ask how they make copper clad stainless
steel
> cookware but i thought it was too dumb and too trivial a question to ask.
> couple days ago i had a copper clad stainless pan delaminate the copper
> cladding and was stunned. made me wonder how they attach it in the first
> place. i'm guessing some sort of furnace brazing process(?). this pan is
> probably over 50 years old, i think this is one of the pans my mother got
as
> a wedding present in the 50's. i've seen stuff (on tv and in books) about
> explosive welding but am totally assuming that's NOT how they make copper
> clad cookware.
>
> http://www.frontiernet.net/~wwixon/delamination.jpg
>
> b.w.
>
Here is how:
http://www.patentstorm.us/patents/4103076/description.html
William Wixon
"Roger Shoaf" <sh...@nospamsyix.com> wrote in message
news:12577461...@news01.syix.com...
>
>
>
> That is really wild. I have never heard of these delaminating. Was there
> something you did like overheat the pot or something?
>
> --
>
> Roger Shoaf
>
probably in it's 50 years of use it might've been overheated, there's no
specific recent incident that i'm aware of though. for months and months
when i put the pot on the stove i could hear little "pops" of steam
explosions in between the copper and stainless, i figured something was
going on but i assumed it was a pin hole in the copper or something. i
think it happened eventually over time, and it probably wouldn't've even
come off completely except i stacked it inside another pot the same size and
when i lifted the one pot out of the other the copper stayed behind (which
startled me). maybe some long slow electrolytic reaction? once water
started getting in there, that ultra thin gap, wicked in by capillary
action, it just kept getting worse and worse? probably a combination of an
overheating incident and water getting in there? i mean, this is not an
earth shattering event but just when someone posted about laminated metal,
and "explosive welding" it reminded me of something i wanted to post
yesterday but thought was too uninteresting to bother you all with.
b.w.
William Wixon
>
-snip-
come to think of it, that's something i've wondered about too. even more.
how in the heck do they make aluminum stick to stainless steel, and for
thousands of heating cycles. it endures terrible abuse, fluctuations in
heat thousands of times, probably like "shock cooling" too (i have no idea
if that's an actual term)(ok, how about "quenching"?).
i tried to read that article and tried to understand it as best i can and it
still amazes me they're able to reliably get aluminum to stick to stainless
steel, and copper to stainless too (under/after thousands of heating
cycles). the article talks about bringing the two metals together under
great pressure, or putting them through a rolling mill. wow. weird. i
wouldn't think putting them through a rolling mill would make them stick,
more like probably resist to an even greater degree wanting to stick
together, like work hardening them both. and so like they make a round disc
of copper stick to a sheet of stainless, but they can accurately register
it?!
hey, i guess for that matter, aren't some u.s. coins bimetallic?
i know they can get dissimilar metals to stick together using explosive
welding, but how to they do it otherwise? that's, as far as i know, a very
rare and extremely limited technique.
b.w.
N_Cook
news:mxLJm.189672$Jp1....@en-nntp-02.dc1.easynews.com...
I would have thought friction welding, probably many to a spin and then
press cut to small discs
Doug White
<snip>
> hey, i guess for that matter, aren't some u.s. coins bimetallic?
>
> i know they can get dissimilar metals to stick together using
> explosive welding, but how to they do it otherwise? that's, as far as
> i know, a very rare and extremely limited technique.
US coins used to be explosively welded. I assuem that is still what they
do. The use large thick sheets, and then roll them out thin. That way
they get a lot of welded metal per bang.
Doug White
whit3rd
wrote:
> N_Cook wrote:
> > I wonder how they "weld" these 2 materials
> > together.
>Explosive welding.
>Simple as that.
This might be the correct answer, but there are fill-metal/reducing
atmosphere/heat solutions that might do a kind of brazing for lower
cost
if you get the materials right. Explosive welding is used for US
coins
because it was possible to mimic the electromagnetic properties of
silver well enough to keep lots of vending machines in service.
I've gotta believe the requirements for a thermostat bimetal system
are loose enough to allow for alloys that don't require explosive
welds.
Baron
I was under the impression that two sheets of material were hot rolled
together and the discs just stamped out complete with the dome shape.
--
Best Regards:
Baron.
William Wixon
"Baron" <baron....@linuxmaniac.nospam.net> wrote in message
news:hd9vjc$bu7$1...@news.eternal-september.org...
how about instead of removing material from the flat surface of the dome to
remove material around the outside diameter? would that alter the point at
which the dome went PING? i was just wondering if the outside edge is
constrained in a bezel, if there was more room to expand there if that would
alter it's temperature rating?
b.w.
Mark Rand
wrote:
>
>
>how about instead of removing material from the flat surface of the dome to
>remove material around the outside diameter? would that alter the point at
>which the dome went PING? i was just wondering if the outside edge is
>constrained in a bezel, if there was more room to expand there if that would
>alter it's temperature rating?
>
>b.w.
>
If there were room, one could add a preload spring to change the set point.
Mark Rand
RTFM
N_Cook
news:MB%Jm.24082$Wd1....@newsfe15.iad...
The use I see them is located fairly loosely in a well in a bakelite disc
that is itself located loosely in the bakelite outer housing
N_Cook
news:dhahf59546oirlspq...@4ax.com...
I might try that , will require adding a small well for the spring
Joe
<wwi...@frontiernet.net> wrote:
>come to think of it, that's something i've wondered about too. even more.
>how in the heck do they make aluminum stick to stainless steel, and for
>thousands of heating cycles. it endures terrible abuse, fluctuations in
>heat thousands of times, probably like "shock cooling" too (i have no idea
>if that's an actual term)(ok, how about "quenching"?).
>
>i tried to read that article and tried to understand it as best i can and it
>still amazes me they're able to reliably get aluminum to stick to stainless
>steel, and copper to stainless too (under/after thousands of heating
>cycles). the article talks about bringing the two metals together under
>great pressure, or putting them through a rolling mill. wow. weird. i
>wouldn't think putting them through a rolling mill would make them stick,
>more like probably resist to an even greater degree wanting to stick
>together, like work hardening them both. and so like they make a round disc
>of copper stick to a sheet of stainless, but they can accurately register
>it?!
>
>hey, i guess for that matter, aren't some u.s. coins bimetallic?
>
>i know they can get dissimilar metals to stick together using explosive
>welding, but how to they do it otherwise? that's, as far as i know, a very
>rare and extremely limited technique.
>
>
>b.w.
>
I remember reading that the process used by the Mint for forming
tri-clad coins was invented (patented?) by the company that makes the
very good but outrageously expensive All-Clad cookware. I think that
their sucess at the coin process led them to introduce the cookware.
Joe
Winston
> As used in thermal switches. Instead of in form of a bimetal strip and
> continuous curving with temperature, these are 0.5 inch diameter and make a
> definite flip from concave to convex at a specific temperature. About 1mm of
> abrupt movement gives a very positive transition for the switch contacts.
> Would it be possible to change the characteristic temperature by grinding
> back a spot/ring/radii? on one face? which face? or would it just destroy
> the action/activation force?
I wonder if one could paint the convex face with fingernail polish as
an etch resist and put the disc in an etching solution to thin the
concave side? Would the relatively smaller 'concave mass' shift the
trigger temperature upwards?
--Winston
--
On YouTube, all the tools have volume controls.
William Sommerwerck
> and make a definite flip from concave to convex at a specific temperature.
> About 1mm of abrupt movement gives a very positive transition for the
> switch contacts. Would it be possible to change the characteristic
> temperature by grinding back a spot/ring/radii? on one face? which
> face? or would it just destroy the action/activation force?
Heaven knows, I don't like reinventing the wheel, but unless you can find
documentation (such as a patent) that explains in detail how these devices
work, and how a particular temperature is set, you're going to have to
experiment.
I again recommend looking for one of those interchangeable thermostats.
Perhaps ripping it apart will reveal the secret!
http://www.gopresto.com/products/products.php?stock=07211
http://www.acehardwareoutlet.com/(uahrtsrsnq0tcxf1wt3tllmg)/productDetails.aspx?SKU=998000074
http://www.advertisingcookbooks.com/si/004123.html
The Presto "Control Master" has been around at least 40 years, and Presto is
still making appliances that use it. (I don't know whether the internal
design or operating principles have changed. The probe part does appear to
be longer and narrower in the current version.)
Roger Shoaf
"Joe" <see_re...@sig.lin> wrote in message
news:i9vif5he68ao4hg00...@4ax.com...
DuPont patented the process of explosion welding that was originally used
for the clad coins, but they stopped using the method somewhere along the
line and now use some sort of rolling method to do it.
http://www.dynamicmaterials.com/data/brochures/1-%20Young%20Paper%20on%20EXW%20History.pdf
--
Roger Shoaf
If you are not part of the solution, you are not dissolved in the solvent.
Bill McKee
Kaiser Steel figured out the original Aluminum to steel "welding" Was used
in the armor plating of tanks. Abrams I think.
Michael A. Terrell
Bill McKee wrote:
>
> Kaiser Steel figured out the original Aluminum to steel "welding" Was used
> in the armor plating of tanks. Abrams I think.
Armco steel, (Now A-K Steel) developed the aluminum clad stainless
steel used for catalytic converters. It was great for body work, too.
:)
--
The movie 'Deliverance' isn't a documentary!
Bill McKee
"Michael A. Terrell" <mike.t...@earthlink.net> wrote in message
news:gP6dneJ2r7RtkWfX...@earthlink.com...
I got to tour the Armco rolling mill in Middletown, OH when it opened. One
of the more impressive experiences. 50 ton block of steel goes into an oven
to get red hot and then sheared off in to manageable pieces. That
eventually are rolled out to very long sheets of steel. Those big rolls of
steel you see at times.
Martin H. Eastburn
Looks like some heat spots here and there and in a ring.
Martin
dca...@krl.org
> As used in thermal switches. Instead of in form of a bimetal strip and
> definite flip from concave to convex at a specific temperature. About 1mm of
> abrupt movement gives a very positive transition for the switch contacts.
> Would it be possible to change the characteristic temperature by grinding
> back a spot/ring/radii? on one face? which face? or would it just destroy
> the action/activation force?
I have been waiting for someone to suggest that the temperature at
which they switch is controlled by how domed the discs are. At least
that is my guess. Suggest you get some rubber and a ballpein hammer.
Test what the temperature is that one switches at, and then make in a
bit more domed and see if that changed the temperature at which it
switches. My guess is that more domed means more change from ambient
temperature before it switches.
Dan
N_Cook
news:453facae-8a15-42ea...@33g2000vbe.googlegroups.com...
Dan
I will give it a go with large ballbearing in a cup and a press. But the
full range of temp (10 to 220 deg C at least) switches all come in the same
size package and the internal spaces and activation pins are the same
dimensions including degree of doming, all that changes is the materials or
construction within the domes. Normally open for the same temp normally
closed is simply just the same dome in, the other way up
Michael A. Terrell
I lived near the 'Project 600' plant for 20+ years. The original
'rolling mill' was built in the late 1800s. 'Project 600' was its
replacement and the first computerized steel mill in the US. The air
was red with rust, until the old mill was decommissioned, years after
'Project 600' was in full operation. It was used to make specialty
steels, while 'Project 600' made steel for the big three auto companies
and several companies that built major appliances. It also made the
steel skin for their 'Armco Steel Buildings' division.
Early pilots used the red cloud as a navigation aid. Some days it
could be spotted 100 miles away. The original plant had so much of that
fine rust clinging to the inside walls and roof that part of the complex
collapsed.
I had a friend who was their analytic chemist. He did all the stack
sampling tests, as well as chemical testing of the various alloys. He
got me a few pieces of aluminized stainless in the late '80s to repair
the sliding doors on my stepvan. That stuff was hard to drill! :)
Ned Simmons
wrote:
><dca...@krl.org> wrote in message
. My guess is that more domed means more change from ambient
>temperature before it switches.
>
> Dan
>
>I will give it a go with large ballbearing in a cup and a press.
Another thing to try is local heating and quenching in order to change
the distribution of internal stresses in the dome.
--
Ned Simmons
isw
Ned Simmons <ne...@nedsim.com> wrote:
It's bimetal; I don't think you want any "unexpected" stresses.
Isaac
Bill McKee
I remember seeing a red cloud above some buildings. Was 1968 and I worked
for NCR in those days and wife and I went down to tour the plant when they
opened it to the public for the grand opening. Was in Dayton for a class.
Growing up 10 blocks from San Francisco bay, did not see a lot of rolling
mills here.
Paul Hovnanian P.E.
> As used in thermal switches. Instead of in form of a bimetal strip and
> continuous curving with temperature, these are 0.5 inch diameter and make
> a definite flip from concave to convex at a specific temperature. About
> 1mm of abrupt movement gives a very positive transition for the switch
> contacts. Would it be possible to change the characteristic temperature by
> grinding back a spot/ring/radii? on one face? which face? or would it just
> destroy the action/activation force?
Pretty difficult to calibrate that change. I'd try mounting a small coil
spring so as to work with or against the direction of the snap. A setscrew
can then be used to modify the spring preload and adjust the snap point.
--
Paul Hovnanian pa...@hovnanian.com
----------------------------------------------------------------------
Have gnu, will travel.
isw
"Paul Hovnanian P.E." <pa...@hovnanian.com> wrote:
> N_Cook wrote:
>
> > As used in thermal switches. Instead of in form of a bimetal strip and
> > continuous curving with temperature, these are 0.5 inch diameter and make
> > a definite flip from concave to convex at a specific temperature. About
> > 1mm of abrupt movement gives a very positive transition for the switch
> > contacts. Would it be possible to change the characteristic temperature by
> > grinding back a spot/ring/radii? on one face? which face? or would it just
> > destroy the action/activation force?
>
> Pretty difficult to calibrate that change. I'd try mounting a small coil
> spring so as to work with or against the direction of the snap. A setscrew
> can then be used to modify the spring preload and adjust the snap point.
If you load it to pop in one direction, then it may be so loaded that it
won't be able to pop back...
Isaac
Michael A. Terrell
That's why they vary the ratio of the two metals when they design the
things. They don't make something, then half ass it till it almost
works.
Paul Hovnanian P.E.
One can play with spring loads and lengths such that this effect can be
controlled to some degree. It has the advantage over the OP's approach
of grinding material off the disc in that it is reversible.
--
Paul Hovnanian mailto:Pa...@Hovnanian.com
------------------------------------------------------------------
Stupidity kills. But not nearly often enough.
steamer
inversely proportional to the radius of curvature; i.e. greater radius
translates to smaller temp changes to make it flip. I was working on what I
call a 'kinetic solar cell' which works very well in theory...
--
"Steamboat Ed" Haas : Currently broke and
Hacking the Trailing Edge! : looking for a job...
www.nmpproducts.com
---Decks a-wash in a sea of words---