Homebrew PCBs

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.





On 02/02/2017 11:59 AM, Harvey Altstadter 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
>
> 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@... [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.
>>
>
>