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Questions relating to designing PCBs
By zbalz
#50437
I'm going to dip into the PCB etching world in a few weeks. From googling, I have a general idea on whats required for the toner-transfer method, but I'm not sure the best places to purchase these parts:

(1) Copper Clad Boards - Places like Digikey have some. EBay also has some, but not sure if its reliable

(2) Etching solution: either,
a. Ammonium Persulphate, or
b. Ferric Chloride

For (2), is that something I can pick up in a general hardware store? [Note: I think I am going to follow the guide found here
Last edited by zbalz on Wed Jun 18, 2008 4:23 am, edited 1 time in total.
By macegr
#50440
Where are you? Jameco usually has good prices on copper-clad and jugs of etchant.
By zbalz
#50446
macegr wrote:Where are you? Jameco usually has good prices on copper-clad and jugs of etchant.
I'm in NJ. I see that Jameco has decent prices on the copper clad through their Jameco Value Line. For jugs of etchant, do you mean GC Electronics as the brand? 32 oz is $14 and 1 gallon is $34. That seemed pricy for a pretty standard chemical. (I could be wrong)
User avatar
By leon_heller
#50447
I buy FeCl3 in solid form. A 250g bag makes up 1 litre of etchant, IIRC.

Leon
By zbalz
#50457
leon_heller wrote:I buy FeCl3 in solid form. A 250g bag makes up 1 litre of etchant, IIRC.

Leon
Do you normally pick it up at a local store? Or do a Mouser/Jameco/Digikey type order?

Also, I was reading on this instructable that FeCl3 shouldn't just be poured down the drain (environmental) How do you guys normally dispose?

That place recommends using muriatic acid with hydrogen peroxide to create a reusable etchant. Anyone with experience in that realm that can enlighten?
By macegr
#50468
I don't recommend muriatic + H2O2. I was excited because you can buy a huge jug of muriatic at many hardware stores cheaply. Later that day, I had a poor-quality etched board, a rasping cough, and every exposed metal surface in the room had a dull, frosted finish. Even a nickel lying on a desk in the next room had a shiny side and an etched side. Anything ferrous turned rusty. This was with a fan blowing fumes out the window, too.

The upshot is that hydrochloric acid is reactive with pretty much anything, produces both harmful vapors and explosive ones, and doesn't really etch any better than other options. The worst that's going to happen with ferric chloride is that you spill it on something and end up with an orange stain. The effort required to properly handle HCl and its byproducts outweighs the slightly higher cost of FeCl.

In my opinion, anyway.

A lot of stuff you'll need for electronics work will cost way more than $14, btw.
By zbalz
#50492
macegr wrote:I don't recommend muriatic + H2O2. ...
A lot of stuff you'll need for electronics work will cost way more than $14, btw.
Thanks for the heads up macegr. I'll certainly steer clear now. I also do understand that electronics can be quite an expensive hobby. But its always good to save when you can, if the circumstances permit. I just assumed that these chemicals were more common and can be found in standard stores. (Wanted to make sure I wasn't paying $20+ for something equivalent of H2O2 that is ~$1 in a supermarket)

So in that case, I'll probably put an order out sometime soon for some boards and chemicals from a common distributor.
User avatar
By leon_heller
#50497
zbalz wrote:
leon_heller wrote:I buy FeCl3 in solid form. A 250g bag makes up 1 litre of etchant, IIRC.

Leon
Do you normally pick it up at a local store? Or do a Mouser/Jameco/Digikey type order?

Also, I was reading on this instructable that FeCl3 shouldn't just be poured down the drain (environmental) How do you guys normally dispose?

That place recommends using muriatic acid with hydrogen peroxide to create a reusable etchant. Anyone with experience in that realm that can enlighten?
I just buy it from my usual electronics suppliers, like Rapid Electronics here in the UK.

I just pour it down the toilet. The iron content is OK (it's actually used for water treatment) and the small amount of copper won't cause any problems. I use it for several months, and regenerate it with hydrochloric acid and hydrogen peroxide.

HCl and H2O2 is quite popular, but has to made up each time it is used and then discarded. It can be dangerous if you don't know what you are doing.

Leon
By Philba
#50505
I'd suggest you look into Ammonium Persulphate. It's more expensive than FeCl but doesn't stain and because it is clear, you can easily see the progress of your etch. I made a vertical tank with a heater and bubbler. Works great and you can see what's happening. I see it at Frys all the time. I've bought it mail order but don't recall where.
By zbalz
#50506
Thank you all for the great tips!
I went and ordered some liquid, and solid, Ferric Chloride along with some boards from Jameco.