Solder balling up and not sticking

[momaka]

Re: Solder balling up and not sticking

With the 30w iron the solder is back to balling up and not sticking.

Grind the tip into chisel shape like you did with your 40W iron. Let iron heat up for about 5 minutes (20 minutes is way way too long... even 10 is too long). Grind tip a little bit again just to clean any oxidation. Do this while the iron is hot. Apply solder on the tip. It should flow nicely this time.

I have a cheap 35W Radio Shack pistol-grip iron I bought ages ago. Still works great. Came with a conical tip, but within the first year I wore it out into a chisel-shaped tip just from usage. When that happened, the iron started working a lot better than before. Moreover, since then, the tip has never again needed a cleaning. I regularly use lead-free solder with it, too. In fact, I don't recall when was the last time I soldered with leaded solder.

[jamesbo]

Re: Solder balling up and not sticking

I just grabbed a Pro Line 70W Soldering Station from Radio Shack. They seem to be on sale at $39.95. And if you are worried about replacement tips becoming unavailable - the Hakko 900M tips work as a replacement.

I picked one up yesterday, they took another $10 off the price, it was $29.99

They also have a digital solder station similar to the Tenma for $69.99 on clearance.
http://www.radioshack.com/product/in...ductId=3132686

[Mansor]

Re: Solder balling up and not sticking

Sorry guys to hijack this thread but as a new member I am not yet allowed to create new thread

I have a cnc V carved small piece of brass very similar to the one on this photo
http://www.embeddedtronics.com/image/cnc/brass.jpg

The text is about 5mm tall, just to give you an idea of how small are the letters
All letters are V carved about 2.2mm deep

I just need the easiest way to fill in these V text engraved with solder
Solder has to be filled properly and a little bit more than the surface to ensure full saturation of the surface as I am going to sand it and make the surface even with brass

now I think I have few options

Solder each letter one by one, probably too much hassle and wont work because the brass bar is quit massive compared to an iron solder and will suck all the heat

another option is to insert solder pieces in the text groves and hammer it a little and then put in the oven, need your opinion on that one

3rd option is same like previous but instead of putting in the oven, use a hot air gun and run through the letters until all letters are saturated

4th use solder paste with hot air or oven

more questions

what would be the best solder type to use in this situation keeping in mind that I would highly prefer the most shiny look of the solder after fine sanding and buffing (mirror finish is the goal)

will I need to use flux or it will be enough with a rosin core solder?

it is not critical to avoid solder on the brass surface between letters as it will be leveled later anyways but just preferred

Hope to receive an answer from you guys as I have very limited soldering experience

Thank you

[stj]

Re: Solder balling up and not sticking

solder paste and oven sounds best.

brass is a bitch to solder unless it has the right flux, you want lead-free solder and flux with Halide in it.

[momaka]

Re: Solder balling up and not sticking

you want lead-free solder...

No you don't, if you want things to look shiny.

Regular 60/40 or 63/37 leaded solder will look much better. You don't even need rosin-core solder (as that will just generate a bunch of unnecessary fumes). If you can find 60/40 or 63/37 solder without rosin core, then all you have to do is just mix a tiny bit of solder paste to make the solder smooth. If not... well, then regular rosin core solder will do .

As for how to heat the solder... personally, I would do it on an exposed heating element electric stove top (and not those infrared/black glass stoves, which aren't very good for this purpose, IMO) - just put the brass plate directly on the burner.

Gas may be too powerful even on the lowest setting, but it depends on the stove, I suppose). Or, if you have some kind of a hot plate/electric skillet, that might work too.

Oven will work fine and you will have good control of the temperature as well, but you can't really do anything to the solder/text until the oven has heated it to proper temperature.

Lastly, let the solder cool slowly. Cooling it quickly will make it less shiny.

[stj]

Re: Solder balling up and not sticking

just make sure the flux contains Halide.
otherwise the solder wont stick to the brass.

something like Kristall505 or HS10 from Stannol

http://www.stannol.de/en/service/documents/data-sheets/