Homebrew PCBs

I am always blown away when I go into the Nail parlor that my wife goes 
to. The smell of acetone in overpowering. It doesn't seem to bother 
anyone that they are inhaling the stuff. I use it, but only in a well 
ventilated area, and always keep it covered.

At one time, acetone was blamed for things that apparently were not 
true. It is shown as having low toxicity: 
https://en.wikipedia.org/wiki/Acetone

Just remember not to mix hydrogen peroxide and acetone together when you 
discard fluids, they form Acetone Peroxide which is extremely unstable 
and dangerous.

Harvey
On 2/2/2017 12:04 PM, Stefan Trethan stefan_trethan@... 
[Homebrew_PCBs] wrote:
> No, acetone is not a carcinogen.
> It is similar to ethanol in toxicity, your liver can break down small 
> quantities.
>
> ST
>
> On Thu, Feb 2, 2017 at 7:26 PM, Rob roomberg@... 
> <mailto:roomberg@...> [Homebrew_PCBs] 
> <Homebrew_PCBs@yahoogroups.com <mailto:Homebrew_PCBs@yahoogroups.com>> 
> wrote:
>
>
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>     I was told by a 70 year old chemistry teacher that I should avoid
>     using ACETONE  because ACETONE is definitely a bad ass carcinogen.
>
>     any ideas here?
>
>     I always wear nitril gloves and run a low speed fan over the work
>     for air flow when I do kitchen etching.
>
>
>
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>
>     On 02/02/2017 11:59 AM, Harvey Altstadter hrconsult@...
>     <mailto:hrconsult@...> [Homebrew_PCBs] wrote:
>>
>>     I did a search on toner density spray, to see what it is. From
>>     several sites that I found, unsurprisingly, that it appears to be
>>     a combination of solvents like toluene and acetone. Further
>>     research brought me to this thread:
>>
>>     http://www.ar15.com/forums/t_10_22/675026_Enhancing_the_contrast__density__of_laser_generated__toner__PCB_transparency_artwork_w__acetone.html
>>     <http://www.ar15.com/forums/t_10_22/675026_Enhancing_the_contrast__density__of_laser_generated__toner__PCB_transparency_artwork_w__acetone.html>
>>
>>     After reading it, it reminds me of two other activities that have
>>     been discussed on this forum. The first is the "setting" of the
>>     toner on Mark Lerman's direct laser print to the board, where he
>>     suspends the board over acetone to let the fumes reflow the
>>     toner, and the second is the cold toner transfer process that was
>>     discussed a while back. This also used acetone with denatured
>>     alcohol.
>>
>>     The thread describes various way to reflow the toner, but in  the
>>     end, they are variations of getting a small amount of solvent
>>     onto the surface, and letting it reflow the toner before
>>     evaporating. This thread brings us full circle to our other
>>     activities, that show that acetone, and possibly, some other
>>     solvents have the capability to improve the toner coverage in
>>     several different approaches to making PCBs.
>>
>>     Other items of interest in the thread have to do with testing
>>     printers and scanners for resolution. Some nice, detailed
>>     instructions.
>>
>>     Harvey
>>     On 2/2/2017 2:58 AM, Kamen Lilov kamenl@...
>>     <mailto:kamenl@...> [Homebrew_PCBs] wrote:
>>>
>>>     Here is my setup:
>>>     * LaserJet 2100 - bought this refurb for about $80, including
>>>     refilled cartridge
>>>     * LaserJer has ethernet module (otherwise it's LPT only,
>>>     difficult to drive in this day and age)
>>>     * Drafting paper
>>>     * Set the density to 5 (default is 3, tried to do this via the
>>>     new Universal Printer driver and failed, then did it by sending
>>>     the specific escape codes via lpr to the network port where I
>>>     have attached it)
>>>
>>>     I used to print two copies on the drafting paper and align and
>>>     glue them perfectly. Worked well. Then I read about and bought a
>>>     toner density spray. It's technically designed for
>>>     transparencies, but works very well with the drafting printouts too.
>>>
>>>     I now only use only one copy. Blackness is perfect, going down
>>>     to 12 mil traces every time and under than (e.g. for 0.65mm smd
>>>     parts) with some care.
>>>
>>>     The critical part of my process now is getting a uniform thick
>>>     coating (I use Positiv 20 on bare stock). Exposure and black
>>>     opacity is no longer causing any troubles.
>>>
>>
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