Homebrew PCBs

Well I needed to make a board this weekend but did not realize that I
was out of the developer.  I use the M G Chemicals 600 series board
with positive resist.  Normally use the M G Chemicals developer which
is Sodium Hydroxide, but can not get it over the weekend.  Never have
found a place to buy the Sodium Hydroxide without ordering it in.

I tried some Washing Soda but so far it does not seem to do anything
to the resist.  How strong should the washing soda need to be mixed? 
or will the washing soda even work on the M G Chemicals positive resist?

Ben

Ben wrote:
> Well I needed to make a board this weekend but did not realize that I
> was out of the developer.  I use the M G Chemicals 600 series board
> with positive resist.  Normally use the M G Chemicals developer which
> is Sodium Hydroxide, but can not get it over the weekend.  Never have
> found a place to buy the Sodium Hydroxide without ordering it in.
> 
> I tried some Washing Soda but so far it does not seem to do anything
> to the resist.  How strong should the washing soda need to be mixed? 
> or will the washing soda even work on the M G Chemicals positive resist?

Try looking for caustic soda rather than washing soda.

It's in supermarkets and hardware shops here.

--- In Homebrew_PCBs@yahoogroups.com, Mark Robinson
<mark.robinson@...> wrote:
>
> Ben wrote:
> > Well I needed to make a board this weekend but did not realize that I
> > was out of the developer.  I use the M G Chemicals 600 series board
> > with positive resist.  Normally use the M G Chemicals developer which
> > is Sodium Hydroxide, but can not get it over the weekend.  Never have
> > found a place to buy the Sodium Hydroxide without ordering it in.
> > 
> > I tried some Washing Soda but so far it does not seem to do anything
> > to the resist.  How strong should the washing soda need to be mixed? 
> > or will the washing soda even work on the M G Chemicals positive
resist?
> 
> Try looking for caustic soda rather than washing soda.
> 
> It's in supermarkets and hardware shops here.
>

So far all I find is Washing Soda, Soda Ash, Sodium Carbonate which
are all the some thing.



Ben

Drain cleaners like Red Devil or Crystal Drano are sodium hydroxide.
It my have little metal shavings in it to make it fizz. Since I use it
to strip negative resist, I am not worried about metal shavings. I am
not sure if it would cause a problem with developing positive resist
as I have no experience with that.

--- In Homebrew_PCBs@yahoogroups.com, "Ben" <bhleavi@...> wrote:

>
> Well I needed to make a board this weekend but did not realize that I
> was out of the developer.  I use the M G Chemicals 600 series board
> with positive resist.  Normally use the M G Chemicals developer which
> is Sodium Hydroxide, but can not get it over the weekend.  Never have
> found a place to buy the Sodium Hydroxide without ordering it in.
> 
> I tried some Washing Soda but so far it does not seem to do anything
> to the resist.  How strong should the washing soda need to be mixed? 
> or will the washing soda even work on the M G Chemicals positive resist?
> 
> Ben
>

Red Devil no longer makes the 100% LYE crystals (THANK YOU METH HEADS)
there is another brand called "ROOTO crystals of Household 100% LYE 
drain opener" this is what I now use to develop the positive resist 
on GC Pre-Sensitized Positive Acting PCB. Add 300mL of tepid water to 
the developing tray. Stir in 1/2 teaspoon of Sodium Hydroxide (LYE 
drain cleaner). Continue to stir until all of the Sodium Hydroxide is 
dissolved. Place circuit board into the developer and gently rock 
back and forth until all unwanted photo resist has been removed. 
Development should take less than 2 minutes. This method is fast, 
clean, and very cheap.

Ron

P.S. If you do find or have the Red Devil crystals, the mix is the 
same 1/2 teaspoon to 300mL of tepid water.

--- In Homebrew_PCBs@yahoogroups.com, "javaguy11111" 
<javaguy11111@...> wrote:
>
> Drain cleaners like Red Devil or Crystal Drano are sodium hydroxide.
> It my have little metal shavings in it to make it fizz. Since I use 
it
> to strip negative resist, I am not worried about metal shavings. I 
am
> not sure if it would cause a problem with developing positive resist
> as I have no experience with that.
> 
> --- In Homebrew_PCBs@yahoogroups.com, "Ben" <bhleavi@> wrote:
> >
> > Well I needed to make a board this weekend but did not realize 
that I
> > was out of the developer.  I use the M G Chemicals 600 series 
board
> > with positive resist.  Normally use the M G Chemicals developer 
which
> > is Sodium Hydroxide, but can not get it over the weekend.  Never 
have
> > found a place to buy the Sodium Hydroxide without ordering it in.
> > 
> > I tried some Washing Soda but so far it does not seem to do 
anything
> > to the resist.  How strong should the washing soda need to be 
mixed? 
> > or will the washing soda even work on the M G Chemicals positive 
resist?

> > 
> > Ben
> >
>

--- In Homebrew_PCBs@yahoogroups.com, "pcb.easy" <rpdavidson@...> wrote:
>
> Red Devil no longer makes the 100% LYE crystals (THANK YOU METH HEADS)
> there is another brand called "ROOTO crystals of Household 100% LYE 
> drain opener" this is what I now use to develop the positive resist 
> on GC Pre-Sensitized Positive Acting PCB. Add 300mL of tepid water to 
> the developing tray. Stir in 1/2 teaspoon of Sodium Hydroxide (LYE 
> drain cleaner). Continue to stir until all of the Sodium Hydroxide is 
> dissolved. Place circuit board into the developer and gently rock 
> back and forth until all unwanted photo resist has been removed. 
> Development should take less than 2 minutes. This method is fast, 
> clean, and very cheap.

OK Thanks,  I did find some Crystal Drano, Had thought I had seen
before some drain cleaner had Sodium Hydroxide but I had looked at the
liquid type before which used something else.  The Crystal Drano works
good.  The 1/2 teaspoon/300mL seemed a bit strong on some of my quick
test that I did. Added more water so it is maybe more like 1/2
teaspoon/400mL water.  Still don't think I could leave it in there for
2 min. and have any resist left on the board.

Home Depot carries 3 different brands,  Drano, some by Zep and then
one other but I can not think of the name and I think it was liquid.

Yes the Drano does have some metal in it but they for the most part
stay on the bottom.

With the M G Chemicals solution I normally brushed the board with a
foam brush but with this found that it was better to just stir the
solution with the brush.  Take the board out just as soon as it looks
like resist has stopped coming off.  

Even at just 1/2 teaspoon/400mL it seems to be stronger than the 10:1
solution of M G Chemicals.

Need to get going with my original project.

Ben

The Rooto 1030 is carried by Ace Hardware Stores.  It is listed as
being 100% Sodium hydroxide.  Maybe the Rooto will not have the metal
pieces in it.

Ben

Ben:

Rooto is the brand that I use, and I bought it at Ace Hardware. Make 
sure that it is 100% Sodium Hydroxide (lye) and not the stuff that has 
aluminum pieces in it.

A friend of mine uses the MG positive PCB and uses the rooto also, and 
like you he had to add a little more water. He said that the develop 
was too quick at 1/2 teaspoon to 300mL of water. 

Ron

--- In Homebrew_PCBs@yahoogroups.com, "Ben" <bhleavi@...> wrote:

>
> The Rooto 1030 is carried by Ace Hardware Stores.  It is listed as
> being 100% Sodium hydroxide.  Maybe the Rooto will not have the metal
> pieces in it.
> 
> Ben
>