Etch Fluid ?? - Page 1
Forum section: electronics / beginners

author: TorqueRanger
author_rank: Frequent Contributor
timestamp: September 14, 2015, 04:12:36 am
content: I have seen around people using Vinger mixed with other chems to etch PCBs .. Has anyone ever tried this and how did this and how did it come out..

author: Psi
author_rank: Super Contributor
timestamp: September 14, 2015, 06:34:53 am
content: Search YouTube if you want to see how well vinegar works. I've not tried it myself.Hydrochloric acid and peroxide works very well and is easily available

author: bitshift
author_rank: Regular Contributor
timestamp: September 14, 2015, 07:12:54 am
content: Quote from: Psi on September 14, 2015, 06:34:53 amSecond this. I've used this on a number of occasions and it works perfectly. For simple boards its much quicker than waiting for a manufacturer + shipping.

author: forrestc
author_rank: Unknown
timestamp: September 14, 2015, 07:23:22 am
content: Quote from: TorqueRanger on September 14, 2015, 04:12:36 amIf you must do it yourself, I'd try some ammonium persulphate (have used with good results), or sodium persulphate (understand it's similar). Seehttp://www.circuitspecialists.com/printed-circuit-board-fabricationfor a USA source for that and other PCB supplies. I'm not a big fan of ferric chloride. What a nasty chemical - not that the others are extremely better, just they seem cleaner and safer (but that's all relative to everything being nasty)Personally with osh park and dirtypcbs.com around, I sure don't see why anyone would even want to bother anymore. Especially with all the disposal worries.-forrest

author: sleemanj
author_rank: Super Contributor
timestamp: September 14, 2015, 07:38:30 am
content: Quote from: evb149 on September 14, 2015, 06:48:31 amI doubt anybody would want to see the "waste treatment processes" employed at a mainland china pcb factory. Probably it involves pouring it into the back alley.

author: coppice
author_rank: Super Contributor
timestamp: September 14, 2015, 08:37:54 am
content: Quote from: sleemanj on September 14, 2015, 07:38:30 amA commercial PCB operation which produced large amounts of waste to be treated would quickly go bankrupt. They need to recover the copper, and recycle the etchant to be economically viable.

author: Chris C
author_rank: Frequent Contributor
timestamp: September 14, 2015, 09:36:33 am
content: I've used this process. 2:3 ratio of 3% hydrogen peroxide and white vinegar, plus some salt.Results can be as good as any other etch solution, if you're willing to wait. A PCB just sitting in the solution with no agitation can take an hour or two! You can get the time down if you actively rub the PCB with a sponge soaked in the etchant, but still, expect no better than 10 minutes.Best disposal method that's realistic to a hobbyist: Neutralize with baking soda. Pour in a wide glass or plastic container (may stain the latter). Set outside in a sheltered area, until evaporated. Scrape up the crystallized cupric chloride and sodium acetate. Use for experiments (like making colored flames), or wrap and dispose of in solid waste, or accumulate in a container and give to hazardous waste facility.

author: KL27x
author_rank: Super Contributor
timestamp: September 14, 2015, 12:19:48 pm
content: I etch with cupric chloride, as do most larger manufacturers. The end product is essentially just more cupric chloride. (Some water and hydrochloric acid are added along the way to keep copper salts from precipitating out of solution). I simply siphon off excess etchant as it's created, dry it in the sun, and then I collect the copper chloride/oxide salts in a Tupperware container; pretty, green, dry (not a hygroscopic sticky mess like ferric) crystals. As long as the copper doesn't get thrown in a land fill where it gets into open water, there is no toxic danger to land animals or humans. I don't neutralize with baking soda; bulks up the end solids.Last I checked, copper is pretty expensive. If scrappers and junkies can get money for copper pipe, I figure copper salts should have some scrap value. I haven't gone quite that far, yet. It'll be another lifetime or two before I have enough to bother with.Simply pouring used etchant down the drain isn't all that bad for the environment, either. As long as you're not on a septic system. But your pipes are a different matter. Fun fact: ferric chloride is used by the ton to treat waste water.

author: technix
author_rank: Super Contributor
timestamp: September 14, 2015, 12:49:43 pm
content: A friend of mine used to use HCl/H2O2/NH4Cl solution as etchant. The trick here is ammonia.

author: Fat
author_rank: Regular Contributor
timestamp: September 14, 2015, 01:45:14 pm
content: 1/3 Muriatic Acid (used in swimming pools and to wash brick, pick it up at the hardware store or pool supply) and 2/3 hydrogen peroxide (druggist or dollar store).Works great.

author: oldway
author_rank: Super Contributor
timestamp: September 14, 2015, 03:21:05 pm
content: Quote from: Psi on September 14, 2015, 06:34:53 amI agree and you can reuse it a lot of times: only add a little more peroxide each time.NB: use concentrated comercial peroxide. (400 vol)Etching time depends from how much peroxide you added.