solder paste safety and usage

[Jamie Morken]

Hi all,

How safe is lead based solder paste? I am doing my first toaster
oven/stenicl soldering and I got some on my hands, it seems to wash off
ok but I am wondering if the lead can soak into the skin etc.. I would
like to use lead free solder paste, if it much safer? Any input on this
would be appreciated, especially a source to buy small quantities of
lead/leadfree solder paste for low cost!

I do this work in my house so I want to make sure I am not creating a
toxic waste dump.

I had trouble with the stencil the first time I tried using it to apply
the solder paste today, I need to find a way to keep the stencil flat
against the board, as it lifted a bit and smudged the paste around. My
stencil is just a sheet of stainless with no bends in it and no frame
(from pcb-pool.com)
http://www.laser-stencil.com/lsuk/info_stencilpool.html

cheers,
Jamie Morken

 

[Ian Stirling]

Jamie Morken <jmorken@shaw.ca> wrote:

Hi all,

How safe is lead based solder paste? I am doing my first toaster
oven/stenicl soldering and I got some on my hands, it seems to wash off
ok but I am wondering if the lead can soak into the skin etc.. I would

Not really.
Wear gloves.
AND DON'T USE AN OVEN USED FOR FOOD!!!!!
You should really do it outside, or at least in the garage.

like to use lead free solder paste, if it much safer? Any input on this
would be appreciated, especially a source to buy small quantities of
lead/leadfree solder paste for low cost!

I do this work in my house so I want to make sure I am not creating a
toxic waste dump.

I had trouble with the stencil the first time I tried using it to apply
the solder paste today, I need to find a way to keep the stencil flat
against the board, as it lifted a bit and smudged the paste around. My
stencil is just a sheet of stainless with no bends in it and no frame
(from pcb-pool.com)
http://www.laser-stencil.com/lsuk/info_stencilpool.html

 

[Frithiof Andreas Jensen]

"CFoley1064" <cfoley1064@aol.com> skrev i en meddelelse
news:20041026110009.03847.00002464@mb-m10.aol.com...

Questions of this type usually receive a better reception on
sci.electronics.basics.

Yeah? That was a wery good reception IMO (I do not think it is 'basic' to
mess around with solder paste, but maybe I am too old ;-)

 

[Rich Grise]

On Tue, 26 Oct 2004 15:00:09 +0000, CFoley1064 wrote:
....

too). Stay away from the no-cleans -- their fluxes tend to be meek and mild.
That may be tolerable in a production environment where everything is
completely perfect, but in the real world of your toaster oven you will have
problems with lack of wetting and poor solder joints -- guaranteed. Just wash
your board with Palmolive green dishwashing detergent and hot water afterward
(Madge: "You're soaking in it!"). Be sure to rinse well and let things dry
thoroughly after -- your toaster oven will come in handy here.

But blow all the water droplets off before hanging it out to dry - even
"deionized" water will leave residue when it evaporates.

As far as holding the stencil down, how about a few 1" square
ceramic tiles, as dead weight in the corners?

Good Luck!
Rich

 

[raven imap]

CFoley1064 wrote:

Hi, Jamie. In solder paste, the solder alloy is in the form of microscopic
balls which can't be absorbed into the skin. The issue would be the flux in
which the solder is mixed. Ingestion is, of course, a big no-no -- lead and
most fluxes are toxic.

I doubt you can absorb much from elemental lead AFAIK the problems occur
with the common compounds of lead, like the base stocks for old paints,
which are readily absorbed.

Steve

 

[raven imap]

Rich Grise wrote:

But blow all the water droplets off before hanging it out to dry - even
"deionized" water will leave residue when it evaporates.

Where we live the water is so soft it leaves no deposits, not nothing at
all. We spray with D-limonene, then rinse.

Steve

 

[Rich Grise]

On Tue, 26 Oct 2004 21:42:04 +0100, raven imap wrote:

Rich Grise wrote:

But blow all the water droplets off before hanging it out to dry - even
"deionized" water will leave residue when it evaporates.

Where we live the water is so soft it leaves no deposits, not nothing at
all. We spray with D-limonene, then rinse.

Well, it's just that if you're not in a class "A" cleanroom, dust mite

feces will get adsorbed out of the air, and get stuck to the board when
the H2O boils off. ;-)

Cheers!
Rich

 

[Rich Webb]

On Thu, 28 Oct 2004 00:08:46 GMT, Rich Grise <rich@example.net> wrote:

On Tue, 26 Oct 2004 21:42:04 +0100, raven imap wrote:

Rich Grise wrote:

But blow all the water droplets off before hanging it out to dry - even
"deionized" water will leave residue when it evaporates.

Where we live the water is so soft it leaves no deposits, not nothing at
all. We spray with D-limonene, then rinse.

Well, it's just that if you're not in a class "A" cleanroom, dust mite
feces will get adsorbed out of the air, and get stuck to the board when
the H2O boils off. ;-)

No shit?


(sorry sorry sorry but it's getting late... ;-)

--
Rich Webb Norfolk, VA