Difference between revisions of "Project:PCB Making/Cupric chloride etchant"

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Revision as of 22:16, 5 February 2011

Ferric Chloride is convenient for small projects, but it is used up and disposal is a pain. An alternative is an etchant that can be regenerated by adding HCl and bubbling air through it.

I understand from some sources that adding HCl to Ferric Chloride will also regenerate it and eventually the etchant changes to CuCl as above. I don't know how carefully that procedure needs to be managed, or whether it's better to start directly with the CuCl bath.

I've set up a bath using this system and made the first pcb. Results are quite encouraging - I kept it at the low end of possible concentrations and ran it it 35 C (the tank will go to about 50), so fumes are acceptably low. It did a decent etch in 15 minutes. I used developer from Mega, which takes about 1 minute.--Artag 16:49, 6 September 2010 (UTC)

There is some HCl in the space (I think it may have been donated by Aden) and some NaOH for titration. I have ordered 500g of Copper II Oxide (CuO) so whe should have most of what we need to get running pretty quickly when the donated tank arrives. I'll try and get a syringe for the titration from Boots, but I'm not sure how friendly they're likely to be...

  • I have plenty of syringes, bought from acuflow. These work very well for measuring, I will bring some in. Although a flask is best for watching the titration, I have used a glass measuring cylinder and found it convenient for both measuring the water (diluting the etchant) and mixing in the NaOh. They can be obtained from wine / beer making shops. - artag