Sweating Joints Problem

[DaffyJeffy]

Hey all. I had a problem sweating joints today and I wanted to see if any of you know what the issue is.

Here's the deal: I've sweated hundreds of joints in my life. I'm very good at it and NEVER get leaks. Now yesterday/today I'm doing a job at my neighbors house and I get 3 joint failures!!! I couldn't believe it. I was using Worthington Select lead free solder. I just couldn't get a good joint
with it. I switched to an old roll of Oaty lead-free I had and no problem - perfect joints every time. What gives? Is there flux/solder compatibility issues I don't know about? A defective roll of solder? What the heck is going on? I was using a MAP torch heated the joint all the way around and did everything perfect but it just wouldn't pull the solder in. Any clues would be appreciated (but bear in mind I know what I'm doing - it's not related to my technique).

 

[ard]

Nevermind.. I was going to recommend talc in the AM

 

[pl_silverado]

I've had issues with lead free solder. Switched to stay-brite 8 with a higher silver content and haven't had a leak since.

 

[matt_i]

I also like the stay-brite #8. It wets the copper better (more surface tension or affinity for the copper or some such phenomenon )

 

[Todd.Brock]

I find that if it's late at night, the wife is bitchin the water has been off for too long, or you are late for something and knew you shouldn't have cut in, then I will have these same problems. I have swapped solder , but narrowed down to these parameters being main cause

 

[cwlo]

I had a lot of problems with the new compliant brass valves. They are a real pain to sweat properly, as the removal of the small amount of lead in them makes it very hard to get the solder to flow properly. I was buying different solder, flux, and nothing stuck. Finally I google searched it, and its a common problem.

 

[pstnbly]

Use tinning flux, non water based if you can find it.

 

[rlitman]

Use tinning flux, non water based if you can find it.

+1 That's what works best for me.

Unfortunately for most here, Home Depot stopped selling the non-water based variety. I cleaned my store out, and now have a lifetime supply.

 

[JackDiddly]

Use tinning flux, non water based if you can find it.

Oatey has a version got it, never looked back. Self tinning Flux is the way to go!

 

[Boomer343]

i use the stay brite 8 as well and the Tec Flux made by LucasMilhaupt.

Local HVAC shops have it. I use it to solder steel to copper.