Sweating Brass Barbs and Bushings on Heater Core

Okay the guy told me at the hardware shop that sweating brass and copper is kinda hard to do, is that true?

This is what I have planned,

I already have a bonnieville heatercore and 3/8 in barbs, I just need to get the bushings to put on the heatercore so the barbs will go on the bushings to make things look neat and clean

does that sound like a sound plan?

Thanks

Sweating?
You need silver silver, flux, and a torch if you're looking for the cleanest method possible to add your own bushings.

obviously I don't know the terminology, silver flux you say?

He means silver solder I think and flux which helps the solder spread out. Both can be bought by the plumbing section.



The local guy at the local store here told me the same thing but I've done multiple with no problem. First heat up the existing tube until you can wiggle it out. I bought a little torch from Lowes that does the job well. Regardless of what torch you use keep the flame pretty low because heating up much more area than directly around the hole will cause the other welds to release which causes leaks. It takes a little longer but well worth it in the end.

Now in most cases you will need to drill out the hole a little to fit a 1/2"ID barb in there. Get the holes just big enough to screw the barb in. Get barbs that fit the holes to make life easier. I like to cut off most of the excess threading on the barb to keep the area inside the radiator free from cavities where air hides as well. It's also a good idea to rough up the area around the hole and on the barb so the solder has something to grab on to.

After that heat the area around the hole and the barb itself up good and hot, you want the solder to stay liquid for a bit when put in place. Spread some solder on both the barb and the area around the hole, just a thin layer, to connect with the next solder. I also place some flux around the barb to help the solder spread out, most burns off but any helps. Now with the torch in one hand and the solder in the other feed the solder in and spread it out nice and even. I use normal old flux core solder, a thick wire helps out here because thinner just evaporates basically. Get it nice and silver all around the edge and fill all the holes. Be careful not to feed too much in or it will just build up inside your core like a big rock.

After you get it all sealed up let it cool then tap on the area around where you soldered to knock any of those solder rocks loose if there are any, then wiggle them out of the barbs. Rinse it out good to get all the flux out. Vinegar helps out, then water. I've never tried silver solder so it might work better but this way has worked for a bunch of cores for me. Take your time and be careful, rushing just ruins your parts.

If all this sounds a little much then liquid plumber might be a good avenue for you. You just pour it on and spread it out, done. Very simple and a little cheaper if you dont have the torch and everything already.