Etching Tank

[ShinyLauren]

So, I've finally decided to have a go at some etching.

I'm going to use PNP and a mini craft iron for the resist, but thought I'd do some (probably a lot of) practicing with brass before I have a go at silver.

Googling suggests that I should use Ferric Chloride to etch brass, which is what they use to etch printed circuit boards, but everything I've read seems to advise the use of a heated 'bubble' tank for etching brass. Would this be the same for silver?

I don't have massive amounts of space in my workshop and was just planning on using a either a mini pickle tank or a glass beaker on a hotplate for my little tank. I'm not going to be etching big things, more just numbers/names/dates onto castings.

Does anyone have experience with etching brass? Do I really need a bubble tank, or would just heating the Ferric Chloride be sufficient?

Thanks!

[Myosotis]

I've etched brass to make pattern plate for the rolling mill and don't use a bubble tank. I just make sure that whatever I'm etching is upside down so that the dissolved sludge falls away and doesn't sit in the pattern you're trying to etch which will inhibit further etching. Also what I do use an old jamjar for the ferric chloride and drill a small hole in the corner of the brass and hook a paper clip through that and then over the edge of the jar so the brass is upside down and at an angle. Seems to work ok. I think other people use brown tape stuck on the back of the metal to suspend it upside down.

[ps_bond]

As an alternative to ferric, which is manky and stains everything, a salt-water electroetch works pretty well for brass. A couple of bits of wire & a battery (or a car charger if you want some speed) in a jar of salt water and away you go.

Ferric chloride won't etch silver well, BTW. Cuts for a bit, then stops. Ferric nitrate does better.

Additionally, you could use the salt water etch to make a steel pattern plate and print onto your silver that way.

[caroleallen]

I use nitric acid and I do what Myosotis said - hang it upside down in a glass dish.

[ShinyLauren]

Thanks guys.

Peter, the ferric chloride is purely to etch the brass - I'd use the ferric nitrate for silver. I'm too scared to use nitric acid Carole!

I'll be etching into curved castings, so making a steel pattern plate wouldn't work in this case.

Going to order some stuff now - exciting!

[ps_bond]

That's good then. Nitric isn't desperately safe if mishandled, but to be honest neither is ferric nitrate.

You can also electroetch silver with a silver nitrate solution.

[Dennis]

You can also electroetch silver with a silver nitrate solution.

That's quite caustic too. It's been used to remove warts.

[ps_bond]

So, strangely, has gaffer tape.
But it doesn't do much good in etching.

Fundamentally, if it eats metal it is unlikely to be good for you - it's a relative scale.

[ShinyLauren]

Another question: if I use steel wire/paperclip to suspend, will the steel not be affected by the etching solution?

[Myosotis]

Another question: if I use steel wire/paperclip to suspend, will the steel not be affected by the etching solution?

Possibly, Peter would know about possible issues with that but I try to make sure it's not in the solution - because I'm etching a smallish rough strip rather than a finished bit of jewellery there's enough spare metal around the edge of the design so that the paper clip stays out of the ferric chloride. I have used a scrap bit of silver wire in the past though when I couldn't find anything else - as Peter says, silver isn't really affected. Could also try the plastic coated paper clips? Or nylon/synthetic beading wire?

[ps_bond]

Yes, it'll definitely be affected. I'd probably use insulated wire to suspend, but copper or brass wire would be OK (for a while!) in the case of your brass etching.
Anything with different electrode potential to what you're etching is going to affect things.

[ShinyLauren]

Right, insulated wire it is then!

I've an old heavy bottomed glass vase, which I'm going to put a glass mini acquarium heater into (this is what a lot of the circuit board people seem to do), so I just need to order PNP and chemicals now.

Exciting!

[ps_bond]

An aquarium bubbler is handy, although the airstones disintegrate in the etchant after a short while; the other way to keep the etchant warm without going too OTT is a homebrew heat pad.
Maplin used to do a cheap bubble etch tank which my wee brother has used quite happily in etching silver, but I can't see it in their lists at the moment.

[caroleallen]

http://www.maplin.co.uk/bubble-etching-tank-611546

Is this what you mean Peter?

[Keia]

I saw a video with Andrew Berry teaching etching, he used a baby bottle warmer with what looked like a plastic beaker inside. There's loads going cheap on ebay & ideal for someone with limited bench space.

[ps_bond]

Is this what you mean Peter?

They used to do a much cheaper one around the £50 mark.
If you want a decent one, look for one from this lot: http://www.megauk.com/pcb_processing_tanks.php
Oh, they also do ferric nitrate.

[ShinyLauren]

Thanks for the links. I did look at some bubble etch tanks, but I just don't have the space for one, and I'm only etching little things anyway.

I'll have a look for that Andrew Berry video.

[Keia]

http://www.youtube.com/watch?v=CHMmP7wpskI Is the direct link. He's really good & very informative. I hope you find it useful =)

[methuselah]

I've found that an easy way to suspend the metal upside down is to glue a bit of expanded polystyrene to the back.

[ShinyLauren]

Have ordered all the stuff (hopefully) to make my DIY bubble tank. Also ordered PNP and a mini iron, so hopefully get to experiment this weekend.

Am expecting it to go horribly wrong to start with, but hopefully will get better with practice!

[Petal]

Have ordered all the stuff (hopefully) to make my DIY bubble tank. Also ordered PNP and a mini iron, so hopefully get to experiment this weekend.

Am expecting it to go horribly wrong to start with, but hopefully will get better with practice!

Etching is on my list for this year Lauren, so it will be interesting to see how you get on and how you find using your DIY bubble tank. (I'm all excited for you!!)

[medusa]

I've etched brass to make pattern plate for the rolling mill and don't use a bubble tank. I just make sure that whatever I'm etching is upside down so that the dissolved sludge falls away and doesn't sit in the pattern you're trying to etch which will inhibit further etching. Also what I do use an old jamjar for the ferric chloride and drill a small hole in the corner of the brass and hook a paper clip through that and then over the edge of the jar so the brass is upside down and at an angle. Seems to work ok. I think other people use brown tape stuck on the back of the metal to suspend it upside down.

if you do this without a bubble tank, is there not a danger of bubbles forming on the etched surface?

I have the surface to be etched hung sideways and periodically brush it with a feather to dislodge the crud and allow the bubbles to float off.

[Myosotis]

if you do this without a bubble tank, is there not a danger of bubbles forming on the etched surface?

I have the surface to be etched hung sideways and periodically brush it with a feather to dislodge the crud and allow the bubbles to float off.
I've used the feather method years back in college when we used proper acid (nitric?) to etch copper and there were bubbles with that method, however it's not something I've had to contend with when using ferric chloride - I don't think I use a particularly strong solution and it tends to be quite a slow etch, maybe that's why no bubbles?

There's someone on the other side that does some lovely etching using Edinburgh etch - I can't remember her saying anything about bubbles but she hasn't posted for ages

[medusa]

hmmmm maybe I should try this new fangled way then! I only ever etch silver using Ferric Nitrate and often wondered if the sludge at the bottom was possibly silver, though it seems unlikely.

[Tabby66]

My only foray into etching has been with nitric and a goose feather to brush bubbles away (in a glass ramekin), pretty satisfactory results but not consistently repeatable (not sure that's good english!!).

What etchant are you using Lauren??