@HW
Ill take some detailed Pics of my etching tank. (I never got around to that part)
My tank (all acrylic) holds the boards just about vertical with the exception that their needed to be at least a small amount of clearance so the parts that were covered up could get properly etched. this is where the challenge is. how does one hold a board perfectly vertical while simultaneously not obstructing/blocking agitation/bubbling.
My boards kind of float from one vertical position to another. I would say 3 degrees max.
But to answer your question directly. I use a double foam airiator. One on each side of the board. The microbubbles are astounding. The pump I use is a left over pump from some long forgotten project.
Most of my tank design was gathered from internet intel. others pros cons etc...
I tried to use all of what I thought were the best ideas.
My preferred method is toner transfer. Most of my projects end up being double sided.
While I could use a CnC machine to do the entire board. I feel the etching makes for a board in the long run. but I do print/transfer/etch both sides simultaneously . I have never tried the photo method. If I did single sided boards this would not even be an issue.
All my project boards start out as 1oz per side boards. which is why I suspect my times are double some of the fastest times posted. I could say their equivalent times for the material being removed. :)
Sam
--- In Homebrew_PCBs@yahoogroups.com, Harvey White <madyn@...> wrote:
>
> On Tue, 3 Sep 2013 20:32:13 -0400, you wrote:
>
> >Harvey,
> >I'm in Tampa
> > looks like were almost neighbors. :)
>
> My Mother in Law lives in Sun City Center, we were down there
> yesterday.
>
> >Mine seems to settle in around olive green. Ive never seen any blue to speak of.
>
> The blue is as it is just starting off, once it's CuCl, it's olive.
>
> >my ingredients are: CVS or Walgreens Hydrogen peroxide, and good ole Home depot Muratic acid sold in 1 gallon jugs.
> >my results are always the same. I have heard of people getting etch times in the sub 10 mins I have never had one etch that fast.
> >perhaps they are using 1/2 oz frp boards? 6 mins vs my 13 is about 1:2 ratio.
>
> I think they are using the 1/2 oz boards rather than the 1 oz boards.
> >
> >My bubbler works extraordinarily well. my tank has the heat option but As i said earlier I get the same results either way.
> >
> >I think the weakest link with my setup is I have yet to find a way to hold the boards perfectly vertical so they etch the same on both sides
> >one side always etches faster than the other (the side getting more bubbles)
> >
>
> That or you take the board out and rotate it 180 and put it back in. I
> have top to bottom etch disparities depending on the bubbler (what do
> you use for a distributor? I use a piece of irrigation fitting
> drilled to match, but it has to be level to work well).
>
> Since I only do single sided etching (and then epoxy the boards
> together) I only worry about top to bottom. It works better with
> toner transfer, but I suspect you are using photosensitive material.
> There are tricks to doing double sided toner transfer on a double
> sided board, but the epoxy method works well enough for me.
>
> try www.dragonworks.info not been updated in years, but it shows a
> few things.
>
> Harvey
>
> >Sam
> >
> >
> >
> >
> >
> >
> >On Sep 3, 2013, at 8:06 PM, Harvey White <madyn@...> wrote:
> >
> >> On Tue, 03 Sep 2013 23:51:48 -0000, you wrote:
> >>
> >> >Forgot to mention.
> >> >
> >> >here is what mine looked like.
> >> >http://thesn1per.blogspot.com/2013/06/diy-circuit-boards-tachometer.html
> >> >
> >> >The color you see is the result after about 1 hour of mixing with a small piece of coper
> >> >bubbling the entire time. I used no heat. Im in Florida the ambient temp is quite hot as it is.
> >> >I tried heat on previous times the results ere the same.
> >> >I will add as time goes on the mixture will become a darker shade of green.
> >> >I hope this helps.
> >>
> >> Hmmmm. Ok. As I first started it, peroxide and HCl, the mixture was
> >> transparent and colorless. Boards etched in about 6 minutes or so (I
> >> did have air bubbling through and did heat the solution).
> >>
> >> As the solution aged, it turned blue/green, not the same shade of
> >> green you show here.
> >>
> >> As it aged past that, it turned a dark green, almost opaque, a slight
> >> shade of olive green.
> >>
> >> Air is used to bubble through the solution as it heats, and is used
> >> continually as the solution etches. I use heat anyway, and the
> >> temperature is about 110 or so F, it could get to 120 but I'm not sure
> >> you want it hotter than that.
> >>
> >> I used the copper in the boards to make the CuCl etchant, no sense in
> >> wasting the peroxide dissolving unwanted copper.
> >>
> >> Not sure what the problem is with what you have, but the color seems
> >> to be off. You should get the standard blue copper sulfate kind of
> >> color to start with.
> >>
> >> With the olive solution (if it turns brown, it's off), adding peroxide
> >> can change it to a blue transparent solution.
> >>
> >> You near Orlando?
> >>
> >> Harvey
> >>
> >> >Sam
> >> >
> >> >
> >> >
> >> >
> >> >
> >> >--- In Homebrew_PCBs@yahoogroups.com, "thesn1per" <mail4sam@> wrote:
> >> >>
> >> >> Pink? should be green or some shade of.
> >> >> Sam
> >> >>
> >> >> Read this.
> >> >> http://members.optusnet.com.au/~eseychell/PCB/etching_CuCl/
> >> >>
> >> >>
> >> >>
> >> >>
> >> >> --- In Homebrew_PCBs@yahoogroups.com, <twgray2007@> wrote:
> >> >> >
> >> >> > OK, I tried bubbling air through the mixture for about 24 hours with no change. I heated to about 40 C and placed a PCB in just to test and after about 25 minutes it had just started to turn pink from etching. The volume was at about 1/2 gallon and to this I added about 1/2 cup of HCL and left the board in for another 30 minutes with little change.
> >> >> >
> >> >> > I think I will now put a lot of copper wire in, at 40 C and let it run to see if it will "take off", as you put it.
> >> >> >
> >> >>
> >>
> >
> >
> >
> >[Non-text portions of this message have been removed]
> >
> >
> >
> >------------------------------------
> >
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> >
> >
> >
>