I Tried this with stranded copper wire instead of solid and it melted much faster. Strip off the insulation and twist it. The individual stands of the wire heat up faster and melt. Worked well. Great post. Thanks

I used to be a weekend welder on classic cars and such and I enjoyed your presentation very much and after all these years I never even thought to try copper wire for small stuff and I was really impressed to see you do it with Mapp Gas! Just goes to show how two heads are better than one. Thanks for the show!

That joint had amazing strength. I'll keep this idea in my bag of tricks for use down the road. Thanks for testing this.

Excellent vid. Great info nugget and well done. Vids like this are why I trudge through the endless parade of useless tool "hack" offerings

Thank you for the education. I've recently invested in Sievert blow torch and burner nozzles so this is very relevant to me. I push items to be brazed into a large tin can packed with rockwool. This supports as well as insulates. I'm planning on getting some 'insulation bricks' as well to make a brazing hearth. I mainly do aluminium welding using 'durafix' rods but hope to do more bronze welding.

For those who might not know….pre-preparing the bond surface with a thin layer of the melted filler material…is called ‘Tinning’.

I always work with some blocks of aerated concrete to keep my heat concetrated. i put the work on a block and put some blocks behind and over it. when working in a vise, i also sometimes work with a wad of ceramic insulation blanket formed behind and little over it. You will get much more heat out of your torches this way. I do not even have mapp, and still am able to do most of the brazing this way. cheers, and thanks for your videos.

Good experiment, I believe the copper likes the more granular structure of cast metals or low quality steel as opposed to HSS or tool steel where the right grain doesn't allow it to grab. Years ago I repaired a truck headlamp bracket using copper(it was done on the road at night, someone hadn't replaced the welding and brazing rod that was usually carried on the service truck) it was meant to be temporary but actually lasted a few months. One thing I will say is electrical wire does come in different grades depending on the use, most is very clean 98% or better pure copper but not all, that could affect the results. Also please be careful grinding or welding around galvanized, it is terribly harmful to you. I want you to be around a long time to make more videos and see what the next tee shirt is!! Be safe

Great video, thanks for that! You might look into custom forming an insulator with "water glass" and perlite. The ingredients are very cheap! Also, there are vids on making water glass, and even now to make a furnace/,oven, but I wouldn't go that far. Basically make a brick with a trough for your work pieces to sit in. This gives you heat on three sides and helps keep the part from moving. One other thought: if you are up to it, look into vids on building an induction heater. You could preheat the thicker part to cherry red without using a bunch of gass. Then quickly move the part to your custom insulator brick, fire up the torch and braze away.

Brilliant video, and very informative thank you for sharing

Damn good demonstration and test. Thanks for this video

Those joints were so strong! Thanks Rob.

I thought using a flux coated brazing rod was convenient but I had no idea how MUCH flux was being distributed. what you said has turned out to be completely true. Since the rod material goes where the flux is and flux melts into a puddle, then the rod goes EVERYWHERE. Adding the flux yourself gives you the control of where the rod melts to. Cheers on that point. I have cleaner brazes thanks to this very true advise. This is the real value of people networking their ideas together on KZfaq. Great post

Thank you, peace and love.

I brazed two pieces of 25x6 mm flat bar together with a large propane burner,each piece was about 150mm long.Did it with comcoat manganese bronze rod.Ibuilt a surround of fire brick around the whole issue to stop heat loss,which i think was your problem ,heat was also conducting through into the vlce.Interesting little video thanks for taking the trouble.

They use copper for vacuum-brazing of heat exchangers in central-heating boilers, so should be good for corrosion-resistance. (Crevice corrosion)

the vice is absorbing all the heat put the work on a fire brick

Great video just thought I would mention we learned in school Acetylene and copper produce highly deadly gas. Yet people still use it for brazing

Great experiment--thanks for posting. On the "cheap as it gets" theme, I remember my father using a piece of coathanger wire to braze a repair on one of Mom's kitchen chairs. He was using oxy-acetylene, of course.

A couple of small, inexpensive fire (hearth) bricks help hold the heat and you can use them as backing, work surface, etc. I use them on my work table to keep from burning anything below.