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Subject: Re: [Homebrew_PCBs] Re: The case for crowd-sourced PCB materials

From: Larry Battraw <lbattraw@...>
Date: 2011-10-12

On Wed, Oct 12, 2011 at 12:32 PM, designer_craig <cs6061@...> wrote:
>
>
>
> Larry
> I got some AQ3000 in Feb of 2010. Genesis had it in quarts on Ebay and I paid about $81 with shipping. You may want to call them and see if they would put a quart up on Ebay buy it now.
>
> At the time I attempted to sell part the quart in 4oz qty for my cost plus shipping -- got no takers.

I contacted them last week about this but they refuse to sell quart
sizes at all since apparently they're concerned about shelf life.
They require a commitment for a certain amount to be used over a
period of time (Likely a large amount) to deal with you.  It was very
discouraging, going from a great eBay-based model to a proprietary,
difficult to work with process that marginalizes all but the larger
users.


> I talked with one of the engineers at Genesis about the 6 month shelf life and he told me it was much better than that but for commercial uses had it set at 6 months. He wouldn't say how long it would last but I keep it in the refrigerator like I did the Shipley AZ111 I used years ago. It was still good after 10 years. I haven't used the AQ3000 lately, guess I should test it one of these days.


As far as shelf life goes I may have been fine with mine which was a
couple years old except for the fact it got frozen in my refrigerator
by accident.  It caused the solids in the solution to separate into a
block of blue gummy stuff and watery blue liquid.  I really wish I had
some more but I'm afraid that without a group buy-in it's not
possible.

>
> I spin coat it on boards then bake at 180F till hard. Use potassium or sodium carbonate to deveolope. I did find I needed to thin it a little with water to get a better spin coat. It's fairly sensitive and Zoltan was able to immage it with his direct UV laser writer with stunning resolution.
>
> Just too many projects and not enought time or money.
>
> Craig

I used to spin-coat it as well and it worked perfectly most of the
time. Thinning it was definitely a necessity to avoid having it too
thick in places.


Regards,
Larry