Solder possible with yellow resin around. [Solved]

It is possible that the original Arduino UNO R3 (made in Italy and in box) has a weld in the rear with yellow resin around. ? :roll_eyes:

Greetings.
Guillermo.

can be cleaned with alcohol and a cotton ? :roll_eyes:

Hi Giullermo,

Your question isn't clear to me.
I get that you mean you see a blob of solder somewhere on your Uno, but not where on that board.
It is also not clear to me whether you have a problem or not, or if you anticipate such problem.
The resin can indeed be cleaned with some alcohol or specific pcb cleaning fluid that does this.
However, the resin doesn't do any harm, it just might look not nice.
There are some pictures available on this site (click!) showing the official board.
You can click on those pictures to have them shown full screen, and if that isn't enough you can even zoom in on those full screen pictures.
So i recommend you to compare your board to those.
If you see something different on your board, to what is shown in the pictures, i'd either take a photograph and upload it in a post, or edit a picture to show where that blob is.
Someone might be able to shed some light on that information provided by you.

My native language is Spanish. sorry.

Affected welding point with a yellow stain, corresponds to one under 16Mhz Quartz Crystal.

I'll upload a photo within a couple of hours. I could not test it fully yet. not think it's a failure. is just a stain of yellow colored resin.

I can try to clean it with alcohol, gently, without damaging the arduino. I am a beginner.

I wonder if this was normal to find a yellow speck surrounding a weld.

That stuff is not conductive, so I wouldn't worry too much.

A note for English speakers:
In Italian, and I surmise in Spanish as well, there are not separate words to distinguish between soldering and welding, so when the original poster writes "weld", English speakers should interpret this as "solder". Ciao, Lenny

Hi Lenny,
Thanks for clearing that.
I suspected this and understood i had to replace the word "weld" by "solder", but it's always nice to know where these things originate from.
I like to speak / write in foreign language like English, and try to understand as much as possible different languages.

@Guillermo:
Don't apologise for your native language, it's a good thing you're at least trying to write in English and you do get your message sent.

As Nick Gammon made clear: don't worry about the resin; it's not going to get you or your board in to trouble.
No need to clean it, but if you want to get rid of it that's no problem either.
And yes, it is common to find these stains.
Boards are cleaned in most cases, but sometimes not all resin is removed.
You'll find more of these stains in your future projects (i hope).

MAS3:
I like to speak / write in foreign language like English ...

Wait, ... English is a foreign language? :smiley:

Yes, to me it is one of my two second languages, next to German.
I'm assuming you speak "outback" as a first or second language too ?

Absolutely. :slight_smile:

Just being playful.

My native language is Spanish. I live in Uruguay.

I removed the stain without having problems. I used rectified alcohol delicately, because I had no isopropyl alcohol.

Thanks everyone for your comments.

Even VODKA has been used with no bad results.

pwillard:
Even VODKA has been used with no bad results.

Unless you drink it...
:stuck_out_tongue: