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9th Nov 2019, 8:59 am | #1 |
Heptode
Join Date: Apr 2011
Location: Gosport, Hampshire, UK.
Posts: 606
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Nail Varnish as Etch Resist
I am drawing a PCB layout with a Dalo pen at the moment. I have two pens that I've had for years and they still work!
There are a couple of large areas of copper that I want to leave and I know from experience that trying to block out a large area with a Dalo pen is not easy! Uses a lot of ink too. I read on another thread on here that someone had used nail varnish as an etch resist so before I go off to the Pound shop to get some, has anyone else tried this? John
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9th Nov 2019, 9:25 am | #2 |
Dekatron
Join Date: Nov 2010
Location: Oxford, UK.
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Re: Nail Varnish as Etch Resist
Back in the day in the early 70s I used nail varnish as an etch resist. If my rather foggy memory looking back half a century is correct, it worked just fine.
Craig |
9th Nov 2019, 11:33 am | #3 |
Dekatron
Join Date: Apr 2012
Location: Worksop, Nottinghamshire, UK.
Posts: 5,554
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Re: Nail Varnish as Etch Resist
Sticky backed plastic works too especially sticky letters for any input/output markings.
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9th Nov 2019, 12:05 pm | #4 |
Hexode
Join Date: Mar 2009
Location: Worthing, Sussex, UK.
Posts: 277
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Re: Nail Varnish as Etch Resist
I used to 'borrow' my mum's nail varnish. It worked very well.
Ging |
9th Nov 2019, 12:19 pm | #5 |
Dekatron
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 14,007
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Re: Nail Varnish as Etch Resist
Yes, nail varnish works well - though it can be a bit tricky to apply (it can drag and form annoying 'strings' if you take your time applying it and it starts to dry).
I alsi tried "Tipp-ex" correction-fluid as an etch-resist, with less-than-impressive results. |
9th Nov 2019, 3:49 pm | #6 |
Heptode
Join Date: Apr 2011
Location: Gosport, Hampshire, UK.
Posts: 606
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Re: Nail Varnish as Etch Resist
Thanks for your replies. I'll give it a go then. Interesting about the sticky backed plastic. I might try that as well. I have a roll of it that I use when I make a front panel for something.
I draw the front panel with Microsoft Paint. Print it on 100g+ paper then cover it with sticky backed plastic. Then glue it to the front panel. So I've got plenty!! John
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9th Nov 2019, 4:30 pm | #7 | |
Nonode
Join Date: Oct 2014
Location: West Midlands, UK.
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Re: Nail Varnish as Etch Resist
Quote:
An alternative at 5that time ( may still be available ) was nail varnish pens. I asked Swimbo to look out for one, but she never seen any except in magazines. |
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9th Nov 2019, 7:31 pm | #8 |
Hexode
Join Date: Aug 2010
Location: Malvern, Worcestershire, UK.
Posts: 347
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Re: Nail Varnish as Etch Resist
I rarely etch boards now but for psu projects etc I have used car scratch repair (clear coat ) repair pens available at little cost for large heatsink or RF groundplane. Readily bought online and in car paint accessory outlets.
Regards Mike |
9th Nov 2019, 11:54 pm | #9 | |
Heptode
Join Date: Apr 2011
Location: Gosport, Hampshire, UK.
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Re: Nail Varnish as Etch Resist
Quote:
John
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10th Nov 2019, 4:19 am | #10 |
Banned
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Re: Nail Varnish as Etch Resist
There are two types of nail varnish too. One is pure acrylic, the type you want, made using acetone and the "cheaper" child safe stuff, which I can't be sure of, but seems to be made from thin PVA glue. It's not so suitable.
Joe |
10th Nov 2019, 12:51 pm | #11 |
Heptode
Join Date: Apr 2011
Location: Gosport, Hampshire, UK.
Posts: 606
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Re: Nail Varnish as Etch Resist
Thanks for that - don't know a lot about nail varnish! I suppose if it smells of acetone, then that's the one. I'll check before I get any in the Pound Shop. My wife is sorting some old ones for me too.
John
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10th Nov 2019, 1:22 pm | #12 |
Dekatron
Join Date: May 2008
Location: Derby, UK.
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Re: Nail Varnish as Etch Resist
The chemical reaction between copper and etchant (traditionally ferric chloride, other chemicals are available) takes place in aqueous solution, so anything that does not let water through and doesn't itself react with either copper or etchant will work as an etch-resist.
Most nail polish is solvent-based and does an excellent job of excluding moisture if it is applied to clean, dry copper (perhaps slightly roughened with steel wool or similar to help with adhesion). There are water-based types available, but they are not yet so common; no doubt mass production and health, welfare and environmental concerns will change this. Usual mantra applies: If in doubt, test it. Pound store nail polish is good stuff to have in the workshop anyway, for general marking and thread locking duties; it's already in a messy-bench-friendly, short, fat, narrow-necked container, and it even comes with its own brush.
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13th Nov 2019, 1:03 pm | #13 |
Heptode
Join Date: Apr 2011
Location: Gosport, Hampshire, UK.
Posts: 606
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Re: Nail Varnish as Etch Resist
Well, I can now report that nail varnish works well! So long as it's the stuff that smells strongly of solvent or something similar.
You will need a bottle of cheap nail varnish remover of some sort to get it off again after etching. White spirit doesn't touch it. My wife gave me an old bottle of varnish that used to belong to one of my children. It's called 'Twilight Teaser' Basically, it's pink and that's not so good as it's close to the colour of the clean copper and not so easy to see where you've been with it. Black would be better along with a fine artists brush if you want fine lines. The brush that comes with the bottle is OK for large areas, ground planes and so on. John
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13th Nov 2019, 1:10 pm | #14 |
Nonode
Join Date: Oct 2010
Location: Tintinara, South Australia, Australia
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Re: Nail Varnish as Etch Resist
Nail varnish remover, cheap or otherwise, is usually acetone based, so anything acetone based can be used to remove it.
One BIG proviso when doing this - do it in a well ventilated place, acetone can have very nasty side effects which I can attest to (in my case, luckily, short term). |
13th Nov 2019, 10:10 pm | #15 |
Nonode
Join Date: Oct 2014
Location: West Midlands, UK.
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Re: Nail Varnish as Etch Resist
Back on #7, I mentioned nail varnish pens.( solves the fine brush problem in #13) Swimbo has found that these are available on e bay for less than a couple of £ . She suggests the Gel coat ones ( no need for UV, as the varnish dries in air), but this type are more resistant to problems .( Nice to have a wife who likes to get involved ).
She also tells me that the stuff that needs to be cured with UV, needs a special remover. She did mention that she'd seen it in Poundland. Last edited by Oldcodger; 13th Nov 2019 at 10:18 pm. |
14th Nov 2019, 6:54 pm | #16 |
Rest in Peace
Join Date: Nov 2010
Location: North Hykeham, Lincolnshire, UK.
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Re: Nail Varnish as Etch Resist
I used nail varnish for all my PCBs. Fortunately I was lucky to find bottles with a nice fine brush!
Given that 0.1" spacing was the standard for most components, I use to draw out the design on 0.1" graph paper then tape it to the board and use a very fine scribe to mark the position of every hole on the board through the paper. I could then remove the paper and use the indentations in the copper as a guide while drawing the design with the nail varnish. |
20th Nov 2019, 4:03 pm | #17 |
Tetrode
Join Date: Jul 2018
Location: Southport, Merseyside, UK.
Posts: 63
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Re: Nail Varnish as Etch Resist
I used to use staedtler lumocolour pens but I found that they dried out if unused for a few months.
The last few boards I have done with Sharpie pens from Tesco. They work really well, they resist the etch and I have to use fine steel wool to get it off. I use a fine point for detail work and a W10 with a wide felt tip for filling in large areas. give them a try, I have good results with them. Mike.
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21st Nov 2019, 11:36 am | #18 |
Heptode
Join Date: Apr 2011
Location: Gosport, Hampshire, UK.
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Re: Nail Varnish as Etch Resist
Mike, I'll have to have a look at Sharpie pens. Tesco you say? I'll make a note of that.
Terry, I used to do something similar to what you describe, but with a centre popper. Lately, I've been using a piece of Veroboard as a template with the hole positions marked on it with a non waterproof pen. Then I clamp that to the copper clad board and drill through with a 0.8mm drill. Then wash the Veroboard so I can reuse it. Once all the holes are drilled, I check that they're all the right size, some may need to be 1mm. Then when all the components fit, I set about drawing the track pattern with a Dalo pen. Once thing I have never managed to do is route a line between two 0.1" holes! This limits what I can achieve with this method and then I resort to a Vero wiring pen. Nail varnish isn't going to help here other than to block off large areas of copper. What I must do is get to grips with Kikad then I could have the PCBs made in China and this would allow me to make more complex boards. Ones with a Z80, RAM and EEPROM and so on. John
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