12 Nov
2005
12 Nov
'05
5:21 p.m.
Subject: Re: removing parts from PCBs
From: William Donzelli <aw288 at osfn.org>
Date: Sat, 12 Nov 2005 17:00:10 -0500 (EST)
To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at
classiccmp.org>
I use a solder pot, filled, so the miniscus (sp?) allows me to just place
the board on the rim of the pot, and all the pads melt nicely. It took me
some time to fine tune the setup, but it works very well. I may never go
back to the torch.
That is by far the best method and also excellent for board you really
don't want to cook (as in ones you fix).
I've used that trick on PCs I wanted that had bad DALLAS DS1287
clock/cmos chips. Its easier then to sand off the epoxy to
access the dead battery for replacement.
Allison
14 Nov
14 Nov
2:02 p.m.
I don't know what a solder pot is exactly, but at one
point I was contemplating fabricating a sort of U
shaped thing to bolt onto the end of a solder iron
(albeit a hefty one). Either sheet brass or copper
would suit the purpose. You can find that sort of
stuph at many hobby shops and even hardware stores
(look for a rack full of stuph with the name "K & S",
sheets, tubing, etc.) You would need a different
"thing" for each size chip you wanted to desolder. If
the ic is known bad, you don't have to worry about
cooking it, though you have to be careful with the
lans on the circuit board.
--- William Donzelli <aw288 at osfn.org> wrote:
__________________________________
Yahoo! FareChase: Search multiple travel sites in one click.
http://farechase.yahoo.com
That is by far
the best method and also excellent
for board you really
don't want to cook (as in ones you fix).
One of the tricks is to get a solder pot the right
size - just big enough
for a 40 pin DIP.
William Donzelli
aw288 at osfn.org
15 Nov
15 Nov
9:46 a.m.
>>>> "Chris" == Chris M
<Chris> writes:
Chris> I don't know what a solder pot is exactly, but at one point I
Chris> was contemplating fabricating a sort of U shaped thing to bolt
Chris> onto the end of a solder iron (albeit a hefty one).
That should work; I've seen things like that.
A solder pot is a pot full of molten solder. Think of a crockpot or a
soup mug with an electric heater in the bottom. Insert bars of solder
and let them melt.
I never understood what those things are meant to be used for; they
show up in tool catalog but never with any explanation. Is component
removal the "official" reason for them? Or tinning wires?
paul
9:54 a.m.
Paul Koning wrote:
That should work; I've seen things like that.
A solder pot is a pot full of molten solder. Think of a crockpot or a
soup mug with an electric heater in the bottom. Insert bars of solder
and let them melt.
I never understood what those things are meant to be used for; they
show up in tool catalog but never with any explanation. Is component
removal the "official" reason for them? Or tinning wires?
They work really well for tinning leads.
Peace... Sridhar
9:56 a.m.
Paul Koning wrote:
I use one to make scuba diving weights from lead I collect at shooting
ranges and from tire dealers. Never used one for anything to do with
electronics, but I'm sure there must be a good reason to use it in this
field.
Dave
>>>>"Chris" == Chris M <Chris> writes:
>>>>
>>>>
Chris> I don't know what a solder pot is exactly, but at one point I
Chris> was contemplating fabricating a sort of U shaped thing to bolt
Chris> onto the end of a solder iron (albeit a hefty one).
That should work; I've seen things like that.
A solder pot is a pot full of molten solder. Think of a crockpot or a
soup mug with an electric heater in the bottom. Insert bars of solder
and let them melt.
I never understood what those things are meant to be used for; they
show up in tool catalog but never with any explanation. Is component
removal the "official" reason for them? Or tinning wires?
paul
7:02 a.m.
At 09:56 AM 11/15/05 -0500, Dave wrote:
LOL! I use one to melt down diving weights and other scrap lead to cast
bullets with. Different strokes for different folks!
joe
Chris> I don't know what a solder pot is exactly, but at one point I
Chris> was contemplating fabricating a sort of U shaped thing to bolt
Chris> onto the end of a solder iron (albeit a hefty one).
I use one to make scuba diving weights from lead I collect at shooting
ranges and from tire dealers. Never used one for anything to do with
electronics, but I'm sure there must be a good reason to use it in this
field. 
10:13 a.m.
As a kid I used one to melt lead to make little toy army men from some molds
my dad brought back from a trip to england.
Then I found a bullet mold and used it to make canon shot for a brass cannon
I made on a friend dad's lathe. Canon, mold, solderpot and powder
all got taken away and thrown out , but we did have a lot of fun before getting caught :)
Most PCB's were produced by passing them over a wave of solder
formed in a big solder pot of sorts :)
Tinning stranded wire was the official reason for its existence ....
I remember a production/shop rule that stated all stranded wire must be tinned
or have an end put on it, if it was to be connected to a screw tab.
The QA people would raise hell if we didn't and send it back for rework.
Bob
On Tue, 15 Nov 2005 09:46:55 -0500, Paul Koning wrote:
>>>>> "Chris" == Chris M
<Chris> writes:
Chris> I don't know what a solder pot is
exactly, but at one point I
Chris> was contemplating fabricating a sort of U shaped thing to bolt
Chris> onto the end of a solder iron (albeit a hefty one).
That should work; I've seen things like that.
A solder pot is a pot full of molten solder. Think of
a crockpot or a
soup mug with an electric heater in the bottom. Insert bars of solder
and let them melt.
I never understood what those things are meant to be
used for; they
show up in tool catalog but never with any explanation. Is component
removal the "official" reason for them? Or tinning wires?
paul
10:55 a.m.
On 11/15/2005 at 9:46 AM Paul Koning wrote:
I never understood what those things are meant to be
used for; they
show up in tool catalog but never with any explanation. Is component
removal the "official" reason for them? Or tinning wires?
One of the very few good ways to tin litz wire that I know of involves a
solder pot.
Cheers,
Chuck
2:42 p.m.
That should work; I've seen things like that.
A solder pot is a pot full of molten solder. Think of a crockpot or a
soup mug with an electric heater in the bottom. Insert bars of solder
and let them melt.
I never understood what those things are meant to be used for; they
show up in tool catalog but never with any explanation. Is component
removal the "official" reason for them? Or tinning wires?
In the old days, they were used to solder wires in electric gear and even
houses - this was before the wirenut came into common use. Somewhere
around here I have a solder pot on a gimballed 2 foot handle, so you could
do the connections in the ceiling fixtures.
OSHA? Who needs 'em.
I have to say that I think using oil for removing parts in just plain
INSANE.
William Donzelli
aw288 at osfn.org
5:16 p.m.
Chuck Guzis wrote:
On 11/15/2005 at 2:42 PM William Donzelli wrote:
Is that the stuff in Cray's? Now we know why they are so much!
I have to say that I think using oil for removing
parts in just plain
INSANE.
Yeah, Fluorinert FC-70 is what you want--boils at 419F; high heat transfer
characteristics; about $100 for 100 ml...
5:41 p.m.
woodelf wrote:
Chuck Guzis wrote:
and then again ... they may have needed the magic 203 degree point. Any
water in
the chips or plastic used would stay liquid!
On 11/15/2005 at 3:16 PM woodelf wrote:
So what is wrong with cheap water? I guess - inert - says it all. Is that the stuff in Cray's? Now we know why
they are so much!
A relative, but not the same stuff. Cray used Fluorinert F-77, which
boils
at about 203F.
6:24 p.m.
On 11/15/2005 at 3:36 PM woodelf wrote:
So what is wrong with cheap water? I guess - inert -
says it all.
Well yes, but remember that Honeywell tinkered with direct water cooling a
bit back in the 70's. I think they used a copper diaphragm between the
water and the chip to conduct heat. I know they had problems with algae
growing in the tubing and that certain algicides had the problem of
corroding copper. IIRC, this was an ECL implementation of an earlier
machine that didn't do much better than 1.5x the original in performance.
As a product, a disaster.
Here's a paper on direct immersion cooling:
http://www.electronics-cooling.com/Resources/EC_Articles/MAY96/may96_04.htm
Cheers,
Chuck
6:59 p.m.
Chuck Guzis wrote:
On 11/15/2005 at 3:36 PM woodelf wrote:
Well yes, but remember that Honeywell tinkered with direct water cooling a
bit back in the 70's. I think they used a copper diaphragm between the
water and the chip to conduct heat. I know they had problems with algae
growing in the tubing and that certain algicides had the problem of
corroding copper. IIRC, this was an ECL implementation of an earlier
machine that didn't do much better than 1.5x the original in performance.
As a product, a disaster.
So did anybody know about heat pipes?
9:19 p.m.
Well yes, but remember that Honeywell tinkered with
direct water cooling a
bit back in the 70's.
IBM did as well, but I do not know the specifics. Their early 80s water
cooling technology, however, is well documented (Sci American, for one).
Someone found that a better way to cool is with a Slurpee mixture.
William Donzelli
aw288 at osfn.org
10:51 p.m.
370 mod 168 used a water chiller. Big ugly water jackets, but they worked :)
Bob
On Tue, 15 Nov 2005 21:19:19 -0500 (EST), William Donzelli wrote:
> Well yes, but remember that Honeywell tinkered
with direct water cooling a
> bit back in the 70's.
IBM did as well, but I do not know the specifics. Their
early 80s water
cooling technology, however, is well documented (Sci American, for one).
Someone found that a better way to cool is with a
Slurpee mixture.
William Donzelli
aw288 at osfn.org
16 Nov
16 Nov
1:45 a.m.
On 11/15/2005 at 9:19 PM William Donzelli wrote:
I got to see the Honeywell setup when the prototype was still being worked
on. A friend worked at the old GE plant in Phoenix and gave me a tour.
The machine was sort of a throwback to the 1940's--it was literally a
walk-in unit with things in free-standing racks with plastic water tubing
all over the place. There were still quite a few GE machines around the
place then.
But I think indirect water cooling (as a heat transfer medium) goes back as
far as SAGE.
Speaking of Honeywell, does anyone collect the pre-GE 16-bit minis?
Cheers,
Chuck
Well yes, but
remember that Honeywell tinkered with direct water
cooling a bit back in the
70's. 
2:55 a.m.
On 11/15/2005 at 3:36 PM woodelf wrote:
Of course plain ordinary automotive antifreeze is a corrosion inhibitor
and toxic enough to prevent algae growing...
Gordon
So what is wrong with cheap water? I guess -
inert - says it all.
Well yes, but remember that Honeywell tinkered with direct water cooling a
bit back in the 70's. I think they used a copper diaphragm between the
water and the chip to conduct heat. I know they had problems with algae
growing in the tubing and that certain algicides had the problem of
corroding copper. IIRC, this was an ECL implementation of an earlier
machine that didn't do much better than 1.5x the original in performance.
As a product, a disaster.
9:24 a.m.
>>>> "woodelf" == woodelf
<bfranchuk at jetnet.ab.ca> writes:
>> Is that the stuff in Cray's? Now we know
why they are so much!
>>
> A relative, but not the same stuff. Cray used Fluorinert F-77,
> which boils at about 203F.
woodelf> So what is wrong with cheap water? I guess - inert - says
woodelf> it all.
Water is not inert, especially not when hot.
paul
9:39 a.m.
Am 16 Nov 2005 9:24 meinte Paul Koning:
>>>> "woodelf" == woodelf <bfranchuk at jetnet.ab.ca>
writes:
>> Is that the stuff in Cray's? Now we know why they are so much!
> A relative, but not the same stuff. Cray used Fluorinert F-77,
> which boils at about 203F.
woodelf> So what is wrong with cheap water? I
guess - inert - says
woodelf> it all. Water is not inert, especially not when hot.
Just add tea and a teaspoon - definitly not inert :)
SCNR
H.
--
VCF Europa 7.0 am 29/30.April und 01.Mai 2006 in Muenchen
http://www.vcfe.org/
14 Nov
14 Nov
9:47 a.m.
>>>> "Allison" == Allison
<ajp166 at bellatlantic.net> writes:
> Subject: Re: removing parts from PCBs From:
William Donzelli
> <aw288 at osfn.org> Date: Sat, 12 Nov 2005 17:00:10 -0500 (EST) To:
> "General Discussion: On-Topic and Off-Topic Posts"
> <cctalk at classiccmp.org>
>
>
> I use a solder pot, filled, so the miniscus (sp?) allows me to
> just place the board on the rim of the pot, and all the pads melt
> nicely. It took me some time to fine tune the setup, but it works
> very well. I may never go back to the torch.
Allison> That is by far the best method and also excellent for board
Allison> you really don't want to cook (as in ones you fix).
I would think the best -- if you can find the machinery -- is standard
rework tools. It seems the standard tool nowadays is a hot air
machine with nozzles shaped to fit the part to be removed. If you can
find a surplus one (new ones are pretty expensive) that would be worth
grabbing...
paul
10:31 a.m.
Paul Koning wrote:
I picked up a Hakko 850 in primo condition for $125 on eBay.
--
www.blackcube.org The Texas State Home for Wayward and Orphaned Computers
>>>>"Allison" == Allison <ajp166 at bellatlantic.net>
writes:
>>>>
>>>>
> Subject: Re: removing parts from PCBs From:
William Donzelli
> <aw288 at osfn.org> Date: Sat, 12 Nov 2005 17:00:10 -0500 (EST) To:
> "General Discussion: On-Topic and Off-Topic Posts"
> <cctalk at classiccmp.org>
>
>
> I use a solder pot, filled, so the miniscus (sp?) allows me to
> just place the board on the rim of the pot, and all the pads melt
> nicely. It took me some time to fine tune the setup, but it works
> very well. I may never go back to the torch.
Allison> That is by far the best method and also excellent for board
Allison> you really don't want to cook (as in ones you fix).
I would think the best -- if you can find the machinery -- is standard
rework tools. It seems the standard tool nowadays is a hot air
machine with nozzles shaped to fit the part to be removed. If you can
find a surplus one (new ones are pretty expensive) that would be worth
grabbing...
paul
6824
days inactive
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days old
25 comments
13 participants
participants (13)
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ajp166＠bellatlantic.net -
aw288＠osfn.org -
bfranchuk＠jetnet.ab.ca -
Bob＠BRADLEE.ORG -
cclist＠sydex.com -
chrism3667＠yahoo.com -
dmabry＠mich.com -
gordonjcp＠gjcp.net -
Hans.Franke＠mch20.sbs.de -
jrice54＠vzavenue.net -
pkoning＠equallogic.com -
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rigdonj＠cfl.rr.com