IR reflective thermometer
Buerste
little as $30 or do I have to spend more? Or should I get a contact
thermometer? Or try to find my thermocouple digital one?(buried in "The
Move")
Michael Koblic
"Buerste" <bue...@wowway.com> wrote in message
news:pIBVm.50789$cX4....@newsfe10.iad...
I suspect the answer is "maybe". I assume you would get one with the
appropriate temperature range. I use one regularly for many purposes: The
quickest way to determine the room temperature in my garage is to take the
temperature of the walls. It was great when trying to determine where are
the heat leaks in the house. It works well when cooking (frying pan
temperature), it is quite reliable in measuring the temperature of the
etching bath (ferric chloride - a big advantage as you do not want to dip
things into that stuff). The one area where it consistently fails is on
shiny metal surfaces. For my heat transfers I use an aluminium plate and it
under-reads the temp by quite a bit. However, it reads the temperature of
the items *on the plate* and that for my purposes is sufficient.
I understand there are thermometers which correct for emissivity but I doubt
that they will be $30.
What I am saying is that even though the thermometer my not do the job of
reading the temperature of the surface of the molten lead for you
accurately, there may be creative ways of getting around that problem.
--
Michael Koblic
Campbell River, BC
Steve W.
The easy way is to attach a thermocouple to the outside of the pot. I
used a simple wire clamp that holds the couple to the exterior of the
pot. Then fire up the pot. When the lead melts use a contact unit and
compare the readings.
--
Steve W.
sta...@prolynx.com
Way too complicated for the purpose. The bimetal thermometer I use is
designed for casting purposes, cost less than $20 at the time. The
temp you need to know isn't the pot's surface temp, it's the internal
temp. And once you get good results, remember where the rheostat
position is on the electric pot control for next time. Both Lyman and
RCBS retail thermometers for casting. They're stainless and won't get
dissolved by hot lead. One of the easiest ways to improve bullet
quality is a good thermometer. You want the lowest temp that you can
get full fillout with.
Stan
Jim Wilkins
There isn't much I can add to the good answers posted already.
I have used professional equipment like the emissivity-corrected IR
thermometers and multipoint thermocouple loggers.
Thermocouples read randomly low unless they are in a deep hole packed
with conductive material. Strapping them to the wall under insulation
doesn't always give a good reading.
Aluminum is awful to read accurately. The IR emissivity varies from
below 0.1 to above 0.9 depending on oxidation, i.e. how long it's been
hot. You can't tell by its appearance.
http://www.engineeringtoolbox.com/emissivity-coefficients-d_447.html
Black heat sinks weren't so bad, a setting around 0.8 - 0.9 made the
IR temperature agree fairly well with an embedded thermocouple.
Notice on the chart that most dark materials like black hi-temp paint
and cast iron are in that area. I'd soot the surface or spray a thin
film of wood stove or barbecue paint.
My personal IR thermometer is a cheapie from Radio Shack that doesn't
read hot enough for molten lead. I use it as MK suggested, to check
the house insulation, and also to find a misfiring engine cylinder.
Thanks for the Christmas list idea.
jsw
Wild_Bill
stainless steel sheathed model could possibly be ideal for molten lead
temperatures.
A bracket attached to the side of the lead pot housing with a ceramic heat
insulator, could be a good way to mount the probe.
--
WB
.........
metalworking projects
www.kwagmire.com/metal_proj.html
"Jim Wilkins" <kb1...@gmail.com> wrote in message
news:c1188b0c-259d-42d0...@h10g2000vbm.googlegroups.com...
Rich Grise
I'd think "it depends". What's the emissivity of molten lead? What's your
crucible made of? What's its emissivity?
Good Luck!
Rich
F. George McDuffee
======
Just my 2 cents worth, but you appear to be going overboard.
People cast lead bullets for 100s of years by simply melting the
lead over a fire and pouring it in the molds. What do you expect
to gain by very precise temperature measurement/control of the
molten lead?
Unka George (George McDuffee)
..............................
The past is a foreign country;
they do things differently there.
L. P. Hartley (1895-1972), British author.
The Go-Between, Prologue (1953).
whit3rd
On Dec 15, 12:52 pm, F. George McDuffee <gmcduf...@mcduffee-
associates.us> wrote:
> People cast lead bullets for 100s of years by simply melting the
> lead over a fire and pouring it in the molds. What do you expect
> to gain by very precise temperature measurement/control of the
> molten lead?
That's a bit disingenuous. Real heat control starts with the kind
of fire you use (propane/air, acetylene/air, MAPP/air, propane/oxygen,
etc.), and our forebears were VERY cognizant of their fire's
properties. A thermometer on a melting pot is just a way to
recover that kind of knowledge even when using a heat
source that's capable of burning the melt.
The expectation, is to gain proficiency.
(OK, so I'm a measurement junkie; my kitchen sports
half a dozen thermometers and a pH meter... betcha
there's other readers on this group who could match
me for micrometers and verniers!)
F. George McDuffee
<whi...@gmail.com> wrote:
<snip>
>Real heat control starts with the kind
>of fire you use (propane/air, acetylene/air, MAPP/air, propane/oxygen,
>etc.), and our forebears were VERY cognizant of their fire's
>properties.
=======
Again this seems overly complex if you are melting lead and lead
alloy. A simple stove type natural gas or lp burner or
electrical hot plate is all that is required.
http://www.vmisales.com/hurricane/63-5111.html
http://www.midwayusa.com/viewProduct/?productNumber=523105
if you want/need a purpose built lead melter see
http://www.midwayusa.com/viewProduct/?productNumber=637732
http://www.midwayusa.com/browse/BrowseProducts.aspx?pageNum=1&tabId=1&categoryId=8660&categoryString=9315***685***
If you shop locally and hit the second hand stores you can do
much better on the prices. I just grabbed the first items I found
on the web.
Buerste
"F. George McDuffee" <gmcd...@mcduffee-associates.us> wrote in message
news:titfi51louiti5k3d...@4ax.com...
> On Mon, 14 Dec 2009 20:34:14 -0500, "Buerste"
> <bue...@wowway.com> wrote:
>
>>Can I use one of there for my lead pot and casting molds? I see them for
>>as
>>little as $30 or do I have to spend more? Or should I get a contact
>>thermometer? Or try to find my thermocouple digital one?(buried in "The
>>Move")
> ======
> Just my 2 cents worth, but you appear to be going overboard.
> People cast lead bullets for 100s of years by simply melting the
> lead over a fire and pouring it in the molds. What do you expect
> to gain by very precise temperature measurement/control of the
> molten lead?
>
>
Reproducibility. The idea is to make the same product every time by
controlling all the variables and have the highest productivity per hour of
good parts. Then, be able to exactly reproduce those conditions at any time
in the future. Sorry, it's in my nature.
Buerste
I have a bottom-pour 20# pot and a bunch of 6 cavity molds. It's easy to
make crap parts in large numbers.
Larry Jaques
<bue...@wowway.com> scrawled the following:
I have a pyrometer floating around here somewhere. I think the limit
is 800F, so it may be in your range.
--
Every day above ground is a Good Day(tm).
-----------
Stormin Mormon
shiny metal I want to read. That isn't useful information
when you want to read molten lead, though. Out of the tape's
useful temp range. And tape doesn't stick very well to
liquids.
--
Christopher A. Young
Learn more about Jesus
www.lds.org
.
"Michael Koblic" <mko...@uniserve.com> wrote in message
news:hg6qb...@news1.newsguy.com...
sta...@prolynx.com
> "F. George McDuffee" <gmcduf...@mcduffee-associates.us> wrote in messagenews:titfi51louiti5k3d...@4ax.com...
>
> - Show quoted text -
Exactly, with each mold there's a small range of temperatures with a
given alloy that you'll get good results. When things go well, most
of my bullets are within .5 gr of each other. The others get
remelted. The cheap bimetal thermometer will be good enough, save
your bucks for a digital scale to weigh them afterwards. You'll be
hard-put, though, to get good results with a bottom-pour pot and gang
molds in my experience, get a fairly large ladle to pour from. Bottom-
pour pots just don't flow fast enough. If you gotta use one that way,
put some charcoal over the top to cut down vapors. Latest Handloader
mag has a lot of myth-busting about casting in it.
Stan
Buerste
<sta...@prolynx.com> wrote in message
news:216fd640-ec23-4e0c...@t42g2000vba.googlegroups.com...
Stan
Thanks! I do have a pot and ladle too. I can fill all 6 in about 12
seconds with the bottom pour. It would be cool to have two spigots!
Buerste
"Larry Jaques" <novalidaddress@di\/ersify.com> wrote in message
news:d0pgi5h3jvue65ouj...@4ax.com...
Send it.
> -----------
Wes
I'm not currently casting due to a lack of lead. I use an immersion probe and a Omega
temp controller with a relay to control my lead pot.
I have a feeling thata IR thermometer would give you a reference value. Both on the top
of melt and molds.
That might be numbers that ties to nothing else but works for you in finding a sweet spot
in casting.
I have both but when I get back in action, casting wise, I'll look up this thread and add
what I learn.
Wes
--
"Additionally as a security officer, I carry a gun to protect
government officials but my life isn't worth protecting at home
in their eyes." Dick Anthony Heller
Jim Wilkins
42512. Does anyone have experience with them or know of a cheaper one
that will read to 1600F or 900C for heat treating steel?
jsw
Martin H. Eastburn
I have used with comparison matches an Extech 'Amp-probe' like jaw current
meeter. It was a hall effect unit and was tested by a large company
and was shown to be a good bargain and ample for the work intended.
I have a 1000 amp HP clamp - but I don't need that often :-)
Martin
Larry Jaques
<bue...@wowway.com> scrawled the following:
>
>"Larry Jaques" <novalidaddress@di\/ersify.com> wrote in message
>news:d0pgi5h3jvue65ouj...@4ax.com...
>> On Mon, 14 Dec 2009 20:34:14 -0500, the infamous "Buerste"
>> <bue...@wowway.com> scrawled the following:
>>
>>>Can I use one of there for my lead pot and casting molds? I see them for
>>>as
>>>little as $30 or do I have to spend more? Or should I get a contact
>>>thermometer? Or try to find my thermocouple digital one?(buried in "The
>>>Move")
>>
>> I have a pyrometer floating around here somewhere. I think the limit
>> is 800F, so it may be in your range.
>>
>
>Send it.
Gotta find it first. It's in the _shop_ somewhere.
--
Indifference to evidence: Climate alarmists have become brilliantly
adept at changing their terms to suit their convenience. So it's
"global warming" when there's a heat wave, but it's "climate change"
when there's a cold snap. The earth has registered no discernable
warming in the past 10 years: Very well then, they say, natural
variability must be the cause. But as for the warming that did occur
in the 1980s and 1990s, that plainly was evidence of man-made warming.
Am I missing something here? --Brett Stephens, WSJ Opinion 12/09/09
Wes
Martin H. Eastburn
Omega.com sells quality at $295 and up. - It comes with options...
http://www.omega.com/toc_asp/sectionSC.asp?section=J&book=temperature
HP for higher costing versions (I suspect)......
put this into a search engine :
Infrared Temperature Measurement Instruments
Martin
Ralph
Mark Rand
>I got a low end HF infrared unit & it reads about 10 deg + or_ Junk!
>
Unless you were always measuring a surface with the same emissivity as the
unit was calibrated with, I'd say your results were pretty good.
Mark Rand
RTFM