Esteemed Advisor
Posts: 3,518
Registered: ‎10-23-2009

What kind of solder for copper pipe?

I am going to re-route some 3/4" and 1/2" copper piping in our home soon, and would like your opinions regarding the proper type of solder to use.


I now have two kinds:


60/40 (Tin, Lead) Rosin core and solid silver solder with no lead.


Which one of the two is proper, or what do you recommend?  I have a Propane torch, no Mapp gas.



Larry.. East Central Iowa

Good enough.. Isn't.
Honored Advisor
Posts: 4,174
Registered: ‎12-31-2009

Re: What kind of solder for copper pipe?

 Most of the new solders sold for plumbing have no lead, but if you want to use what you have the 60/40 should work just fine....  clean the ends of your connections well, put on your paste flux, slide parts together, heat and let solder flow into joint....wipe clean..


My personal opinion is that so little lead can leach out of the connection that the fearmongering about using it (similar to the business about mercury in fillings) is just that...fearmongering....  you don't have enough lifetimes to worry about it.


The silver solder may actually have cadmium in it, which is likely worse for a water system (and possible ingenstion).


Honored Advisor
Posts: 1,907
Registered: ‎10-24-2009

Re: What kind of solder for copper pipe?

Fear  mongering or not, building codes require use of lead free (ie. less than 2%) solder.  Rosin core is designed for electronics use not sweating copper pipes.  Using for sweating pipes there is a separate flux applied after the copper has been cleaned.  Then the pipe and fitting are heated until they melt the solder, drawing it into the joint. 

Honored Advisor
Posts: 2,998
Registered: ‎10-28-2009

Re: What kind of solder for copper pipe?

Most hardware stores have presolderd fittings for plumbing. They already have solder in them that is approved for drinking water. All you have to do is fit them together and apply heat. They are more expensive but if you have to buy solder anyway they may actually work out to be cheaper for you.


Steve K

"Good judgement comes from experience, and experience--well, that comes from poor judgement."
- Cousin Woodman

My Youtube Channel
Honored Advisor
Posts: 3,331
Registered: ‎10-24-2009

Re: What kind of solder for copper pipe?

 First the silver solder requires a high temperature to melt so a propane torch may not do it.  

 While it is required to use lead free solder, the rest of the house was probably done with the 60/40 solder.

 Get some paste flux (very important) and do as p-toad said.   Do not depend on the flux core for this.

  Get the paste flux on the parts right after cleaning.     Roly


Senior Contributor
Posts: 414
Registered: ‎11-03-2009

Re: What kind of solder for copper pipe?

[ Edited ]

Amateur is right.  Lead free is the way to go as far as codes.


Pick up Nokorode flux, best stuff on the market IMHO.


And while your there, pick up a couple tanks of MAPP gas.  It burns hotter than propane.


And maybe an asbestos sheild for those tight spots along with the hangers for the pipe.


And a good water bottle with a good sprayer for those occassional times so you don't have to steal the old ladies ironing/hair sprayer.

Of course I don't look busy!!!

I did it right the first time!!!!