Monday, August 10, 2009

Home cooked PCB etching - part 1

I saw this excellent Instructables on easy PCB etching and have been itching to give it a try ever since. I popped into the local Radioshack to pick up the bits, but was dissapointed that they had neither the ferric chloride solution nor the copper boards. So, when we were up in Santa Rosa for the mini Maker's Fair (see Lin's blogpost for more on that) I ran into the Radioshack up there and was lucky (they'd only just restocked them). Tonight, after the battle of the bed-times, I thought I'd give it a test run. For a proper run, I'm going to have to decide on a board to make, get some transfer paper and print out the design at work (no laser printer at home).

The instructable mentioned that a sharpie should be enough to mask the board, so I drew out a test pattern:

Imaginative, eh? I guess I could have gone computer programing 101 and used "Hello World!" instead.

So, next step was to add ferric chloride solution to a sponge and get scrubbing. The only plastic gloves we've got in the house are 'small' so I figured I'd risk it and just try keeping my fingers out of the way as much as possible. I used a dollar store, sponge on a stick, dabbed on a small amount of ferric chloride solution and got scrubbing.

About 5 minutes later, nothing had happened. A bit of an anti-climax from the promised '"1-minute etch" but I persevered for a little while longer and added a bit more solution to the sponge. I couldn't tell if the black liquid that was forming was to do with the etching process, or if it was just me scrubbing off the sharpie marks...

Another 5 mins of scrubbing and a few more dabs of solution yielded a glimmer of hope:

You can clearly see some of the copper being cleared from the top of the board. A few more minutes and most of the board was clear. Being impatient, I stopped there and used a "Mr Clean magic eraser" to clean off the remaining sharpie marks (no nail polish remover in our house, but plenty of need for powerful grime removal ;) ).

Sweet! It works! Time to create something more functional!

1 comment:

流浪汉 瑜伽 Yoga Tramp said...

Today (6.30am) the sky is still darkness but we already on the way to climbing mountain. This is a dangerous road , die the most cruel death if fall down overhanging . We can't see our hand, sometime we move left hand will touch owl, move right hand will touch snake. Sometime the cool wind is come, 14th July is due (chinese ghost day), i think is "brother & sister" follow us climbing mountain.