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joella
23-08-2018, 01:26 PM
Hi All, It looks as though the easiest place to aquire ferric nitrate crystals from would be ebay, so I plan to buy some from there. I was planning on just using tap water, instead of distilled but wanted to know if anyone knows if there is any reason not to do that? and I'm also wondering what other people do with their solution once it is used. Thanks
Sue

misspond
23-08-2018, 03:43 PM
I get my crystals from eBay and have made mine up with tap water (because I was keen to get using it and didn't have any distilled water) and don't seem to have any problems with it. I think I've been using the same batch of etchant for about a year now (although I don't use it regularly, maybe every couple of months for smallish items like rings and most recently bangles) and it's not showing any signs of failing yet.
I keep it in a plastic lidded tub inside a slightly larger lidded tub because it leaves quite a stain on surfaces (and when I'm etching I place it on a hot water bottle full of hot water to speed the process up). Not had to dispose of it yet so can't help with that part, I'm sure someone will be able to help.

ps_bond
23-08-2018, 03:53 PM
Depends on your tap water. Here, I've got incredibly alkaline water (last time I measured it was at 270ppm CaCO3, which is quite hard) to deal with, so chalk tends to precipitate out rapidly (and can affect chemical reactions). An alternative to distilled is to use deionised water; I buy mine from the local country store but it should still be available in any decent car parts place (even Halfords).

joella
23-08-2018, 04:11 PM
Wow misspond, I can’t believe how long your solution has lasted, I wasn’t expecting it to last nearly as long as that - do you top it up or has it lasted that long without topping up? Thanks for the info.
Thanks Peter, my kettle doesn’t really fur up much, so I think it should be fine, but good to know I can get deionised from Halfords.
Thanks to you both for the info.

misspond
23-08-2018, 07:51 PM
Yes, I think I've been lucky with my tap water - I've no way of testing it but a quick trip to Halfords will get you what you need.
It lasts ages Joella, you get some sediment in the bottom which is the silver that's etched away but don't let that stop you from using it. I don't think I have topped it up, don't recall doing so anyway. You should get an info sheet with your crystals telling you what weight of crystal to mix with water, but I went with slightly more water than was recommended with the plan of adding a bit more crystal if there was too little of a "bite" from the etch. So long as you store it securely then it's all good. Once it stops working as well as I like then I'll top it up with more crystals. I only bought the smallest amount possible, about 250g I think, and have only used half of it so far because this is just a hobby for me. If I started to make larger etched items like cuffs then I'd need to up the amounts.
I love etching, I haven't tried out all of the different ways of putting resist on the silver yet, but I love the results I get and hope to play around more soon.
I look forward to seeing what you do!

joella
23-08-2018, 08:11 PM
Ah, I’m planning to use pnp for my resist, and maybe have a little play with bees wax too. What are you using?

ps_bond
23-08-2018, 08:18 PM
PnP, stop out varnish (shellac based), nail varnish, PVC electricians tape in some areas...

joella
23-08-2018, 09:17 PM
Peter, would the stop out varnish you mention be the same one cookson’s sell - mylands black polish? Or is that a different thing. I hadn’t thought of using pvc electricians tape. Thanks

Dennis
23-08-2018, 10:12 PM
When I return to my part time course in the autumn, there will be that tank of murky solution, with everyone's copper pieces afloat in it. They will have bits of polystyrene foam taped to the back to keep them upside down, so any deposits tend to fall off. Dennis.

vsilvered
24-08-2018, 10:19 AM
Currently electro-etching with silver nitrate and using sticky-backed vinyl designs (cut in a Silhouette Cameo cutter) as a resist. Thinking of trying Copper Nitrate as an etchant which apparently last longer than Silver Nitrate.

misspond
24-08-2018, 12:23 PM
For resist I use Sharpie oil paint pen, nail varnish (and use nail decoration plates to add random designs) and have used Staz-On ink but that tends to float away too quickly for my liking. I've yet to play with toner ink direct from paper or with PnP and transparencies/UV light - but they're all on my list and sitting on a shelf waiting for me to have a go. As Dennis says you can attach your metal to polystyrene to float it in the solution, and for rings and tube I use a length of dental floss attached with gaffer tape to the sides of the outer tub.
Wooden chopsticks or coffee stirrers are handy for a bit of gentle agitation/general poking/lifting things out, and don't forget a good supply of bicarb for neutralising at the end (although I'm sure you've done your homework and know all of this) :D

joella
24-08-2018, 01:36 PM
Hi vsilvered
Now you are just showing me up as I’m too lazy to go down the electro etching route, it has always seemed like it would be such a faff - probably should though, if it’s more environmentally friendly.
Yes misspond, I was planning on polystyrene islands using double sided sticky tape. I don’t like stays on much either, doesnt seem all that appropriately named to me. Dental floss is a good idea, i’ll remember that. Everyone seems out of stock of the oil based sharpies just now (bizarre). Think I’m gonna try transparencies cos if I can get that to work I won’t have to bother with the v expensive, short shelf life of the pnp.