Acid core solder?!?!?

[Fuddy1952]

Who uses acid core solder, and how?
I know it's supposed to be for plumbing, and as a retired electronic technician I soldered all day every day with rosin core for 43 years!
I tried using acid core just now trying every trick...copper tubing shiny as a new penny, flux, various heat...nada.
I used solid core+paste flux...no problem. I've used rosin core for plumbing work and never a leak. Dad showed me how to solder when I was a kid in the 50s!
I've never been able to use acid.

 

[Industrial Toys]

Solder has changed. The new lead free stuff is garbage if you ask me.

I was on a job once working on a nurse call system. I needed to solder something and they only had acid core on site, so thinking, this is just simple low voltage stuff, not really electronic.

Man, did that come back to bite me. That gooey flux is conductive!

 

[k0ua]

Never EVER use acid core for anything electronic. Acid core is for soldering steel gutters together.

Yes lead free solder of electronics is not worth picking up for free in the street. It is near useless. It won't "wet out". Pure garbage. AND on top of that it grows "tin whiskers" after a few years and will destroy electronics. It is a part of planned obsolescence of electronic devices. If someone offers to give you a roll of lead free solder, run. By the way I have a full pound roll I will be happy to give to anyone that I actually hate.

 

[Industrial Toys]

I pick up any rolls of old solder, resin or acid if I come across it.

 

[Fuddy1952]

So right about acid core and electronics. Never ever use it... I just can't see how to use acid core for gutters or anything!

 

[Industrial Toys]

Well certainly for copper pipe? What else would you use?

 

[jaxs]

What else can you expect when big brother tell's what's best for us and see's that that's all we can find?:smiley_aafz:

 

[k0ua]

Well certainly for copper pipe? What else would you use?

You don't use acid core for copper pipe either. You use solid 95/5 for anything that comes in contact with potable water and you apply a flux specified for copper pipe. You use acid core for galvanized steel gutter.

 

[Industrial Toys]

Oh, I certainly do. I never understood the hysteria. Not much of the lead or paste ever touches the inner surface. In fact, I would have no issue using acid on heavy copper conductors. It cleans the copper and makes the solder flow nicer.

I'm also making the assumption that the acid in acid core solder is the same stuff in the solder paste. But I think that stuff has changed too. The old stuff made your open sores sting worse, so I know it has to be better!

 

[tjkubota93]

Supposedly acid core will eat the pipe away after many years.

I use oatey #95 tinning solder and their lead free solid core for plumbing. It works well. Any other flux I have used, that solder didn't work.

This is the last thing I used it on. Also rebuilt the service coming into the house.

 

[jaxs]

. The old stuff made your open sores sting worse, so I know it has to be better!

:yes: Remind's me when I was a kid,dad met another farmer coming down a country road and one offered the other
a drink of whiskey. First came the wipeing off neck after cap was removed,tilt the bottle and make bubbles,followed by wheezing and snorting then "hot dam,that's good stuff".

 

[jaxs]

Someone didn't get the memo because 3 ads for electrical solder are popping up at top of this page,all of them claim to be acid core.

 

[Stimw]

Acid core is good for soldering radiators and moonshine stills.
Used to be good for copper water pipe before the lead police got involved.

 

[jb1390]

I use acid core solder when I need to solder to old vehicle or trailer wiring, often times black due to corrosion. The only trouble is that the flux is extremely corrosive. It will however, strip off whatever corrosion exists on the wire and allow solder to wick. If I need to do this, I strip the wire way back, tin it with acid core, then clean with brake cleaner and finish the joint with rosin core electrical solder.

 

[kenmac]

I have never used acid core for copper potable water lines, or anything else 95/5 with added flux, or this https://www.amazon.com/Harris-Solde...ocphy=9056941&hvtargid=pla-571305387295&psc=1

 

[RNeumann]

Plumber here-

We could occasionally make a water tight connection with acid core. But the reality is for 99% of the soldering we do it’s flux paste and solder.
To put it another way- in the book and or lab I’m sure acid core works. But not in the field- it isn’t clean enough or controlled enough.

 

[Alan W.]

Supposedly acid core will eat the pipe away after many years.

I use oatey #95 tinning solder and their lead free solid core for plumbing. It works well. Any other flux I have used, that solder didn't work.

This is the last thing I used it on. Also rebuilt the service coming into the house.View attachment 588304View attachment 588305

That tinning flux is the only thing I too have found that will allow me to solder copper pipe with the lead free solder.

 

[Industrial Toys]

Isn't the flux paste what's in acid core?

What is the "Flux" paste?
What is the "Acid" in acid core?

 

[tjkubota93]

That tinning flux is the only thing I too have found that will allow me to solder copper pipe with the lead free solder.

I figured it out by accident, just using what I had.

After discovering the lead free worked better with one type of flux than the other, I googled it.

There is alot discussions about what works and what doesn't. Some guys swear by this or that brand. I do have to say, after getting positive results with my combo, it would take alot to make me switch.

 

[Tractor Seabee]

I grew up in a sheetmetal/HVAC shop in the 40s & 50s. Acid core solder was not a known product. On Galv we used pure muriatic (hydrocloric) acid swabbed on. For copper, brass, SS and others we took the muriatic and added zinc to it. When it stopped foaming that was our flux. Later on acid core turned up but never did find a use for it as it did not get to where it need to be quick enough. Acid fluxes were always a no no on electrical work. I left the sheetmetal side and went to commercial/industrial refrigeration work and industrial pipefitting.

I have no idea what the SM shops use now that acids in the form we used are now a no no. Not even sure they solder stuff any more, seems flashings and gutters are gooped up with caulk stuff. We soldered all exterior metal even vertical seams.

Along the way several fluxes were introduced to replace acid and most of them did not work well for piping. Acid fluxes for copper piping went away about 10 years ago. I find the newer water soluble fluxes work real well. Just completed a dual cartridge water filter system with copper pipe the other day for my house. 20 joints and all look good and test OK.

Ron