Soldering brass to copper help....PLease!

**b33p3rmcg** · 11-25-2010, 06:21 PM

New install. No Water involved. Need to get outside wood boiler online but I am having a heck of a time soldering brass fittings to copper. I am cleaning copper and brass extremely well and pasting both. Heating the joint not the copper pipe. The solder eventually melts at the joint but does not flow into the joint. It seems the copper pipe is getting hotter than the joint and the solder is just rolling off the copper even though I am applying the heat to the brass joint and constantly touching the solder to joint to see if it will flow. What am I doing wrong? I have no problems copper to copper but the heavier brass to copper I can't get to flow correctly. I'm thinking maybe I am using the wrong solder? Any advice would be appreciated.
I'm real close to buying threaded fittings to finish the job but hate to waste the money I already spent on sweat fittings....some are costly.

**Gsalet** · 11-25-2010, 08:58 PM

when you say brass fittings do you mean cast copper fittings? (copper water fittings that look like brass)
what size pipe are you trying to solder
what type of flux
typically you put the heat at the end of the fitting socket away from the copper tube, when the solder melts it sucks in towards the heat, if you are heating at the visible joint the copper will over heat and the solder will roll off and not suck in

hj · 11-26-2010, 04:34 AM

There is no difference between soldering copper to copper and copper to brass, other than the small difference in time to heat the joint, (and there is NOT a different solder to do it), therefore you are doing something wrong, but we cannot tell you what it is from your description.

**shacko** · 11-26-2010, 03:14 PM

How old is you flux? they will go bad and cause exactly the prob. you're having

**b33p3rmcg** · 11-26-2010, 06:17 PM

I really appreciate the replies. You are telling me the same thing others I know have told me so it must be me. I am using propane and a friend said try map gas. I'm hitting the (what is probably cast copper..shutoffs, drain valve T's, elbows to put an air eliminator on etc etc) fittings about 3/4 - 1" back from the copper with propane. I'm heating it for well over a minute. But when it's hot enough to melt the solder, the solder just rolls off. Heat it some more and still rolls off.
The solder I have is Lenox brand 95/5 .118 3mm Hope that helps. I really don't know the different solders I should use so let me know what you think.
I'm trying to solder 3/4" and 1" fittings.
I was thinking the flux was fresh until I got thinking about where I bought it in response to your question. It was definataly an un-opened can but it's either old or came from a big box store. I don't remember buying it from the local plumbing supply store with all my other supplies. I will try a new can of flux. Regardless the flux I'm using is Oatey No.95 Tinning Flux.
I said I was heating the joint but what I meant was I am heating the copper cast fitting not the joint or copper pipe.
Again all help is extremely appreciated. I really need to get this wood boiler online. Thanks again.

**Basement_Lurker** · 11-26-2010, 07:14 PM

My guess is that you are trying to solder 3/4" (doing 1" fittings as well is ridiculous) fittings with a DIY bernzomatic propane simple flame kit. Those kits can barely handle 1/2" copper, let alone the larger sizes. You are probably not heating correctly in the first place, and by the time you finally do start to get the joint within the proper temperature range, you have managed to burn away all of your flux.

**jimbo** · 11-27-2010, 05:14 AM

Some good points by lurker. If you haven't completed a joint by one minute, the flux has or will be burned away. Direct the flame at the socket...the area of the fitting that the copper is actually inside. If you look at the flame, you see a long, wide, lighter blue area, and right in the middle, less than an inch long, is a smaller darker blue area. The tip of that dark blue is the hot spot. Probably need to get your flame a little closer.

That propane torch will suffice for copper couplings, elbows, up to 1", but wrot copper fittings and especially valves will be a challenge for it.

**b33p3rmcg** · 11-27-2010, 05:30 AM

Yes I am using the DIY bernzomatic propane simple flame kit. I will get map(spelling?) gas if that's what I need to do. I have soldered up to 1-1/4" copper pipe fittings with propane and never had problems. Also soldered shutoffs of the 3/4" size before without issues. I am not a professional and I admit that. I am just a guy trying to complete a DIY project and am asking for advice. I appreciate all help and critiques positive or negative.
As far as heating it wrong, I get a nice size flame and hold it so the tip of the cone is on the joint approx. 3/4" -1" back on the fitting. I try to heat it up evenly around the fitting. The solder gets applied on the opposite side of the fitting that the flame is hitting. Once flowing I remove the heat and keep feeding the solder. It just won't flow into the fitting.
So from what you are saying it's taking too long for the fitting to heat up and by the time it does the flux is gone. So the Map gas should correct that?

Jimbo, You posted while I was typing this. Thanks for explaining the hot spot to me. I'll still get some Map gas and fresh flux and give it a try. Thank You!

hj · 11-27-2010, 07:16 AM

95/5 solder is one of the most difficult ones to use, especially for a DIYer. Get conventional solder and heat the fitting ON the socket where the copper is inserted, NOT 3/4"-1" back, whatever that means. If you are using water soluble flux, it WILL get "burnt" if is is overheated and cause the symptom you describe. And once it is burnt, the only cure is to take the joint apart, reclean it, and reflux it.

**b33p3rmcg** · 11-27-2010, 01:22 PM

HJ,
Great Information! Thanks. I'm not sure what conventional solder is? 60/40 or something like that? I'm sure the guys at the plumbing supply will know. I'll have to give them crap for selling a rookie the 95/5 in the first place. 3/4" back on the Socket. Sorry. I know what I'm thinking but don't always explain it right. Thanks again!

**shacko** · 11-27-2010, 01:55 PM

This is one of the solders that I've been using for years, easy to use and doesn't require extremely high temperatures.

**jimbo** · 11-27-2010, 03:03 PM

http://www.silvaloy.com/silvabrite100.php A lot of folks like the silvabrite 100, but actually it is not a lot different than 95/5. Both of those do require a working temp. 50 to 100 degrees hotter than 60/40 PbSn, which of course is lead based and not legal for plumbing. Just watch the heat, use good flux. I do like the Oatey tinning flux, but a lot of guys on here see to like the no-corrode water soluble , as well.

**b33p3rmcg** · 11-27-2010, 06:33 PM

I'm ok with lead based solder if I can buy it? I'm using it on a closed heating system so I don't think it'll poison me or the kids. I still wonder how we are still alive with all the lead based products we grew up with?(Born in the early 60s)? Can't solder til Tuesday due to work schedule but I am once again confident(not cocky) that I can finish the job thanks to all the helpful replies. In fact I'm betting on starting my first fire Tuesday afternoon. OK Wednesday afternoon at the latest.
I can't say Thanks enough to everyone. I will definately post back with what I'm sure will be positive results!
Thanks,
Bill

**asktom** · 11-27-2010, 06:47 PM

I'm not sure Mapp gas will burn correctly with the torch you have, if you are burning the flux you don't need more heat anyway. You might want to stick with propane.

**b33p3rmcg** · 11-28-2010, 05:49 AM

I was planning on buying a Mapp Gas kit. So torch would come with it. Mapp gas and solder that suits my soldering abilities and I should be good to go....right? Assuming I can use the torch properly.