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NickD
12-11-2017, 09:21 PM
Hi,
Have been trying to etch copper but only had one consistently even result.
2 probs: I diluted with 25% water and now I've put it all back in the one container am wondering if I shouln't've.
I've been using Sharpies but having to renew design at least twice during process.
I remember once using some sort of plasticky wood sealant but have a feeling I may have had a clearout since then.
I'd appreciate any tips although I think I've had it with buying new pens.
Nick

Dennis
12-11-2017, 10:22 PM
Hi Nick, Sharpies are ok for touching up small deficient areas, but the traditional resists are stopout varnish, applied with a brush, or toner from a laser printer (not inkjet), printed onto acetate or PnP sheets and transferred with a hot iron.

The etchant should be diluted so that the process is quite slow and that the resist stays in place.

I think you should do a lot more reading around the subject and watch U Tube tutorials directed at jewellers. Dennis.

china
13-11-2017, 03:24 AM
How old is your ferric oxide, my brother made circuit boards and we discovered that is goes off over time and be almost useless
You can purchase etch resistant pens at electronic parts suppliers,

art925
13-11-2017, 07:47 AM
I don't etch copper but here are a few tips, try adding some citric acid to a sample of ferric chloride ro revive it. I also warm my etchant, but find electro etching more consistant. If drawing your own design, most use sharpie paint pens as a resist or nail varnish pens but I have never found them here in NL. To create my resist I use photosensitive / photoresist film and expose to uv light using acetate prints and self drawn images. This way there is no reversal of the image needed as in the laser printer transfer method. Etching is full of variables, explore every you tube there is, you have to find a method in every step that works for your set up.
Have fun.

NickD
13-11-2017, 09:39 AM
I don't etch copper but here are a few tips, try adding some citric acid to a sample of ferric chloride ro revive it. I also warm my etchant, but find electro etching more consistant. If drawing your own design, most use sharpie paint pens as a resist or nail varnish pens but I have never found them here in NL. To create my resist I use photosensitive / photoresist film and expose to uv light using acetate prints and self drawn images. This way there is no reversal of the image needed as in the laser printer transfer method. Etching is full of variables, explore every you tube there is, you have to find a method in every step that works for your set up.
Have fun.

Thanks e.one for your help. Good to know you're there.I have actually been watching a few instruction/tip sharing tubes but haven't seen one where the dilution is mentioned which made me wonder where I got my 25% from.
Thanks all

Dennis
13-11-2017, 10:01 AM
Before applying resist the metal needs to be degreased with a toothbush and scouring powder or pumice, until a film of water can coat it evenly.
As deposits form on it during etching, it is best to float it upside down, by attatching a small piece of polystyrene on to the back with double sided tape, as a float.
You also might like this: http://www.lawrence.co.uk/shop/etch.pdf, although a slower etch preserves the resist. Dennis.

NickD
13-11-2017, 10:31 AM
Yes, thanks Dennis , I'm doing all that but it's just frustrating to need to take out the copper rinse/ degrease and then reapply the resist 3 times in one etch. What I'm trying to do is freehand designs and in my case they don't allow for such easy application with a brush. Some folk swear by pens and others at them. It's a work in progress and it keeps me off the streets.

art925
13-11-2017, 02:28 PM
Out of interest Nick, what was the original concentration of your FC? The pdf from Dennis suggests 40%, but seems strong to me. Following all the scrubbing and degreasing of your copper, try a wipe with acetone.

NickD
15-11-2017, 06:26 PM
Out of interest Nick, what was the original concentration of your FC? The pdf from Dennis suggests 40%, but seems strong to me. Following all the scrubbing and degreasing of your copper, try a wipe with acetone.

Yep, it's 40%. That seems to be standard . I'm not sure I've scrubbed, degreased and used acetone every time so I'll try that ( just got to get a design together!)
Thanks again all.
Nick