Some eyelets reluctant to accept solder

[Simcha delft]

Hi Everyone - from Simcha in New Zealand. I'm new here, though I've been around on other amp boards for a few years.

Normster posted recently, "I get a faster solder joint with eyelets and it's much faster for me to populate the board."

.....which spurred me to post this question about hard-to-solder eyelets....
The guitar store where I work 2 days is making a batch of 5 watt tube amps, and I'm building the electronics. Of course there's nothing basically new about a 12AX7 + EL84 guitar amp, but it's had a lot of tweaking with the gain and EQ for each stage, and the end result sounds quite impressive.
Currently, I'm using up the last of a bag of keystone eyelets I got from Mouser several years ago. Although they look clean and silvery, even when new they were always reluctant to 'wet' properly when soldered.
If I install them in a board and then scour them with a rotary wire brush they solder quite normally where the brass is exposed, but there seems to be something about the original tin or solder plating which doesn't accept normal tin/lead cored solder.

This problem is manageable while I'm assembling the initial batch of boards myself: I just wire-brush the crap out of them, and (re)tin them all before filling the board. But this takes time and really shouldn't be necessary. I've never had this problem with turret tags, but like Normster, I prefer to build with eyelets.

I would like to teach my apprentice to fill and solder the next batch of boards....and before than I'd like to have a supply of eyelets which will accept solder without problems.

Has anyone experienced similar problems? Can anyone suggest a source of better eyelets. Lead-free is acceptable, but not necessary.

[Normster]

I haven't had the problem with my own boards using Keystone eyelets from Mouser. However, I did get a batch of predrilled/eyeletted boards from a kit supplier that had the same problem. I used a scotchbrite pad and then wiped the boards down with alchohol. Probably better would be to dab liquid flux on each joint before soldering.

[ayan]

Hi Everyone - from Simcha in New Zealand. I'm new here, though I've been around on other amp boards for a few years.

Normster posted recently, "I get a faster solder joint with eyelets and it's much faster for me to populate the board."

.....which spurred me to post this question about hard-to-solder eyelets....
The guitar store where I work 2 days is making a batch of 5 watt tube amps, and I'm building the electronics. Of course there's nothing basically new about a 12AX7 + EL84 guitar amp, but it's had a lot of tweaking with the gain and EQ for each stage, and the end result sounds quite impressive.
Currently, I'm using up the last of a bag of keystone eyelets I got from Mouser several years ago. Although they look clean and silvery, even when new they were always reluctant to 'wet' properly when soldered.
If I install them in a board and then scour them with a rotary wire brush they solder quite normally where the brass is exposed, but there seems to be something about the original tin or solder plating which doesn't accept normal tin/lead cored solder.

This problem is manageable while I'm assembling the initial batch of boards myself: I just wire-brush the crap out of them, and (re)tin them all before filling the board. But this takes time and really shouldn't be necessary. I've never had this problem with turret tags, but like Normster, I prefer to build with eyelets.

I would like to teach my apprentice to fill and solder the next batch of boards....and before than I'd like to have a supply of eyelets which will accept solder without problems.

Has anyone experienced similar problems? Can anyone suggest a source of better eyelets. Lead-free is acceptable, but not necessary.

I had that very same problem with Mouser eyelets about 6 or 6 years ago. The eyelets eventually tinned, but I had to heat them up and try soldering onto them, then wick off whatever solder took, etc. A real bad batch, but luckily I never had the same problem since then.

Gil

[stoo]

What sort of solder are you using. I find very thin solder doesn't work well because it does not contain enough rosin (flux), 1.2mm works for me!
Stew

[Ed de Jager]

Hi Simcha!
Long time no see!
Hope you are doing well!
Greetings from the Netherlands.
Ed de Jager(EdJ from ax84)

[BobW]

The flux, as Normster suggested, works well.

Here's a penny wise and pound foolish story,

I bought eyelets from a hobby store, and after installing them on a board, I found out the eyelets were brass plated alunimum. Needless to say they were impossible to solder, and I ended up replacing all the eyelets. now I perform the magnet test to all before installing.

[dragonbat13]

I use a paste flux used for plumbing and a small stiff bristled acid brush to brush flux into the eyelets. after the joint cools I use a small brass brush to clean the joint.

[pila]

The plumbing flux is an acid based flux. It would require a good cleaning to get any residue of the acid off, like a little scrubbing with water/baking soda mixed. Seems like less hassle to toss the no-good eyelets and get some good ones.

PILA

[LOUDthud]

Solder is available with several different types of flux today. I find the best is called RMA. Rosin Mildly Activated. I believe type RA is more activated and may work better on tarnished eyelets. There are water soluable fluxes intended for surface mount parts but these contain acid and should be removed from the board after used. There are also "No Clean" fluxes but in my experience, these cause leakage problems and are very difficult to remove.

Have you ever noticed the different smell that comes from soldering on an old amp with old flux around the eyelets? Sometimes, old solder gives the same smell. Does flux age? Could old flux not work as well? I think flux seems to work better at higher temperatures.

[FUCHSAUDIO]

http://www.ccis.com/home/hn/index_files/Page2.htm

This stuff is the best ! RoHs compliant, and works well.
Minimal cleanup requirements. Good stuff.

[Ed de Jager]

I`m not sure if people around here know but Simcha is considered to be the best OT maker around by a lot of people.I hope he will be hanging around here some more.
Ed

[drz400]

I use tin plated brass eyelets, they work perfect.
Used to use the brass ones which can be trouble.