Brazing copper

   / Brazing copper #11  
From and old pipefitter; certified sil brazer: Good info above but some not so good. If all your joints are copper to copper you can use what is called Phos Copper or Sil-phos. Both do not need flux on copper to copper. For 1/2 copper tube and fittings you should be ok with a prestolite air-acetylene torch, air/propane may be iffy. I have done up to 1 1/8" OD that way. Mapp gas and O/A are OK but easy to overheat. The joints are heated till the brazing metal sucks up onto the joint like soft solder does. Copper to steel or brass/bronze requires at least 15% silver alloy and flux. For all brazing the materials need to be bright and shiney. As pipes get larger mapp gas, propane/ox, or O/A are needed to get enough heat.

Terminology: Brazing is a lower temp process and the joints are filled by capillary attraction whereas Bronze Welding only deposists on the surface like other welding except it does not fuse with the base material.
 
   / Brazing copper #12  
You guys know they stopped making MAPP gas in 2008?

All the stuff they sell today is fake. It's just hopped up propane.

I thought I was imagining things, when I noticed it was not heating as fast as it used to.
 
   / Brazing copper #13  
From and old pipefitter; certified sil brazer: Good info above but some not so good. If all your joints are copper to copper you can use what is called Phos Copper or Sil-phos. Both do not need flux on copper to copper. For 1/2 copper tube and fittings you should be ok with a prestolite air-acetylene torch, air/propane may be iffy. I have done up to 1 1/8" OD that way. Mapp gas and O/A are OK but easy to overheat. The joints are heated till the brazing metal sucks up onto the joint like soft solder does. Copper to steel or brass/bronze requires at least 15% silver alloy and flux. For all brazing the materials need to be bright and shiney. As pipes get larger mapp gas, propane/ox, or O/A are needed to get enough heat.

Terminology: Brazing is a lower temp process and the joints are filled by capillary attraction whereas Bronze Welding only deposists on the surface like other welding except it does not fuse with the base material.

Marked as answer - He is right on the money.
 

Tractor & Equipment Auctions

2014 MACK GU (GRANITE) (A50854)
2014 MACK GU...
Kubota 24in Quick Attach Compact Excavator Tooth Bucket ONE PER LOT (A51039)
Kubota 24in Quick...
2015 MACK GU713 (A50854)
2015 MACK GU713...
2021 Cat D5 LGP Dozer (RIDE AND DRIVE) (A50774)
2021 Cat D5 LGP...
2023 Case IH 4412F 12 Row 30 In. Row Spacing Folding Corn Head (A50657)
2023 Case IH 4412F...
2021 Kubota RTV X900 4x4 Utility Cart (A50322)
2021 Kubota RTV...
 
Top