Finally I etched my first board but... :/

[patroclus]

Yes, that's what I thought, but I cleaned the board very well with water, and then with this "liquid used to clean painted nails" (sorry, don't know how you say it in english.. I think acetone).

That's all...
How shoul I clean it now? It may have some dirty, as after drilling, I didn't clean it again, just remove the little pieces of plastic with soft paper..

What should I do?

 

[Nigel Goodwin]

Yes, that's what I thought, but I cleaned the board very well with water, and then with this "liquid used to clean painted nails" (sorry, don't know how you say it in english.. I think acetone).

It's called 'nail varnish remover' in the UK, acetone is probably one chemical which is used for it.

That's all...
How shoul I clean it now? It may have some dirty, as after drilling, I didn't clean it again, just remove the little pieces of plastic with soft paper..

What should I do?

You need to clean the copper so it shines, use a mild abrasive to do it. You can buy abrasive blocks specially for cleaning PCB's, but I'm sure some of the PCB makers on the site will offer their own suggestions.

It's important that the copper is perfectly clean, you shouldn't touch it with your fingers after cleaning, as the grease from your skin prevents solder 'sticking' properly.

 

[patroclus]

What kind of mild abrasive?
Isn't it ok if I clean it with alcohol, water, 'nail varnish remover', or any other common product?

 

[Nigel Goodwin]

What kind of mild abrasive?

I'm sure someone will make some suggestions, but as I mentioned before, you can buy abrasive blocks for the purpose. Have a look at https://www.maplin.co.uk and search for HX04E.

Isn't it ok if I clean it with alcohol, water, 'nail varnish remover', or any other common product?

No, none of those remove the layer of copper oxide from the surface.

 

[patroclus]

I read that a normal saucepan cleaner (wire of cooker) is fine to burnish the surface. Then you sweep with a soft clothe.
Can't the copper layer be damaged by burnishing?... that would be very bad at this stage.

 

[patroclus]

I did more work, after some burnishing with a common scourer, I managed to get off some oxide (I don't know why it happended )
But I sracthed a little bit the board. Soldering is now a bit easier, as solder sticks a bit more to the copper pad, but just a bit. the only way of doing "more or less aceptable" joints is to use plenty of flux...

so far, 3 out of 4 joints come out poor... I don't know what to do to not spoil my board.. Any help? thanks..

 

[laroche73]

poor solder connections

You might consider using something like "Tinnit" https://www.web-tronics.com/er-18.html

If you don't have any, here's a simple (but time-consuming) alternative. Take some solder wick and saturate the end with solder. Then, drag the solder wick across the traces with your soldering iron on top. To save time, just do this around the pad areas that need be soldered. I used this method many years ago to pre-treat traces, the combination of flux & solder in the wick leaves a nice lead/tin coating on the pads that's easy to solder to.

 

[patroclus]

And why does this happend? What should I do next time to avoid this?
thnks

 

[Trini]

I think your problem is not proper cleaning of the copper surface. That showed up when the etch resist did not adhere properly to the copper and started to allow the ferric chloride through to the copper.

I have used several brands of permanent markers, nail polish or varnish as someone called it (on this tropical isle the brand name Cutex is a household name for any brand of nail polish) and Sharpie pens as etch resist.

For cleaning copper I use a generous amount of scouring powder on a damp, not dripping, scouring pad called "Scotch Brite" by 3M and lots of arm and wrist movement and pressure. I also use "Brillo pads" which are fine-mesh metal pads impregnated with scouring powder. This even works with copper with that green stuff on it.

After proper cleaning, the board is wiped dry with paper towels or toilet paper. I then use a paper towel with some Lacquer thinner and wipe the board thoroughly while holding it by the edges. If you are doing the artwork by hand then place more paper towel over the copper where the heel of your wrist would rest.

After drilling I remove any burs on the copper side and clean again with thinner and tin ALL pads with holes (burrs prevent the cleaning pad fro accessing the entire area around the holes. You could also tin all traces to prevent oxidation.

Now if the holes are too large around the component leads you will have difficulty soldering and you will end up with solder blobs.

Good Luck.

Trini

 

[Trini]

I think your problem is not proper cleaning of the copper surface. That showed up when the etch resist did not adhere properly to the copper and started to allow the ferric chloride through to the copper.

I have used several brands of permanent markers, nail polish or varnish as someone called it (on this tropical isle the brand name Cutex is a household name for any brand of nail polish) and Sharpie pens as etch resist.

For cleaning copper I use a generous amount of scouring powder on a damp, not dripping, scouring pad called "Scotch Brite" by 3M and lots of arm and wrist movement and pressure. I also use "Brillo pads" which are fine-mesh metal pads impregnated with scouring powder. This even works with copper with that green stuff on it.

After proper cleaning, the board is wiped dry with paper towels or toilet paper. I then use a paper towel with some Lacquer thinner and wipe the board thoroughly while holding it by the edges. If you are doing the artwork by hand then place more paper towel over the copper where the heel of your wrist would rest.

After drilling I remove any burs on the copper side and clean again with thinner and tin ALL pads with holes (burrs prevent the cleaning pad fro accessing the entire area around the holes. You could also tin all traces to prevent oxidation.

Now if the holes are too large around the component leads you will have difficulty soldering and you will end up with solder blobs.

Good Luck.

Trini

 

[patroclus]

Thanks for all the tips