brazing at home?

well i want to melt two pieces of metal together that have low melting points (maybe tin or copper) with out a fancy welding equipment.

can anybody help me make a very simple and primitive welding method please?

Reply to
sam annex
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Tin will be tricky, unless you mean "tinplate".

Read up on brazing and/or silver soldering. Maybe you mean "soldering." That would be the simplest. Buy a cheap disposable-bottle gas torch.

Keep it all clean. Have fun.

Reply to
A.Gent

charcoal block and mouth fed blowpipe. very cheap to set up.

it takes a fair bit of skill to use, though.

Reply to
bridger

The more you tell us about what you want to accomplish the better the information.

For example, to join two pieces of copper you may need to stack some insulating fire brick so as to form a corner to concentrate the heat. You can use Sil-Phos brazing rod without any flux, but you won't actually be melting the copper pieces together. Instead you will be adding more metal. This works best for lap joints.

Dan

Reply to
Dan Caster

You left out the alcohol lamp....He'll need that too unless he's been hitting the sauce pretty hard...

I've still got my old alcohol lamp, It's the kind with a multi faceted glass bottle which lets you stand it at an angle for better working access.

I've still got the little Lenk alcohol torch I "moved up to" from my lamp and blowpipe start.

Thanks for the memories...

Jeff

Reply to
Jeff Wisnia

well fancy would be like a propane torch or any regular welding tools that you would normally use

Reply to
sam annex

do you have a gas stove? that will work for silver soldering pieces up to 3 or 4 inches long....

Reply to
bridger

well sorry for all the confusion and hastling but i did like you said and i read up on it all and i've decided that brazing is the most realistic method to accomplish the joint i want.

(though i can't find any standard tempurature for melting points)

does anybody know a way to do this with out a regular welding torch/ or a way to make a makeshift torch?

Reply to
sam annex

You still haven't mentioned exactly what it is you are going to do.

Your original post mentions tin (melting point 450°F) and copper (melting point 2000°F). You solder copper with tin!! If you meant tin as the colloquialism (sp?) for thin steel sheet ("tin cans"), then yes a standard brass braze (m.p. circa 1650°F) would work. A $20 propane torch will barely get you there in terms of heat; some insulating firebricks backing up the work will heat things up faster.

Tim

-- "I have misplaced my pants." - Homer Simpson | Electronics,

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Reply to
Tim Williams

snipped-for-privacy@hotmail.com (sam annex) wrote in message news:... ...

Hi. I tried the makeshift torch approach, and it did not work well. Maybe others have more patience, but it did not work out well at all for me. First, I thought it was a problem with heat conduction from the brass brazing rod, but this was not the case. The propane flame just didn't give enough heat to melt the rod. This was a Bernzomatic brass rod with a 1620F working temp. I tried a torch design from backyardmetalcasting.com (Lionel Olver design) and it was starved for air, and did not work correctly. There was also a lot of huff and puff, and the thing was not even able to melt brass rod (1/8") without a workpiece. It was able to melt copper wire, or at least oxidize it, so it was not a problem with temperature. It was a problem with heat. This was a waste of time. I needed to get some brazing done, so I bought a used plumber's air acetylene torch with a Prestolite handle. This worked so much better that unless you are absolutely broke, you should really consider this. You can get these torches around here, if you are patient, for about $100.

Now, if you are too broke for this solution, and you really want to fool around (like me), you can try a few other tricks. Note that these did not work for me, but that does not mean that they will work for you.

1) I found an old microwave oven at a garage sale that they were willing to sell me for $3. Now, $3 is pretty easy to come by. It is even within panhandling range. I stripped the oven down to the transformer, and cut the HV secondary off with a hacksaw. Big mistake. Never do that; instead cut the weld and split the transformer with a chisel. The secondary comes right out. I rewound it with #10 wire. Had to spend $5 for some transformer tape, but old grocery bags works almost as well, and you gotta eat. Somebody discarded an old AA carbon zinc battery on the bus, and I stuffed this in my pocket with nobody the wiser. This was used, in conjunction with some old copper water tubing, to make a carbon arc torch. This beast was just the opposite of the weak propane torch. It creates a brush-like violet arc that dances all around. This arc will instantly melt even decent sized mild steel, like old desktop AT cases. The burnthrough is so rapid and uncontrolled that this technique is difficult to use for brazing. Perhaps with a dual carbon torch, and some kind of current limiting, it will work. But, I only found one AA battery on the bus. Try Wal-mart for D and C cells. They are $1 for a pack of four or so. Also, a saltwater resistor might give better results. Don't shock yourself or burn your eyes. To be continued...I haven't given up on this one yet. 2) Others may have had better luck with this other low budget approach. Build a side draft tuyere forge. You need a tuyere. In a moment of weakness, I coughed up $5 for a piece of 1 1/2" pipe. Silly. If you walk around, "Handicapped Parking" signs have just the right sized pipes. I am not encouraging illegal vandalism, but if you are in a bad enough neighborhood, others will have done the dirty work for you and you will be able to surreptitiously sneak off with the precious pipe. No need to fret over the forge body. Just use wood and nail split tin cans over it. Or, if you are lucky, you can find an unguarded construction site where they are putting up HVAC ducting. A quiet mission will result in all the galvanized flashing that you need. Again, I am not advising immorality. Scavange their cutoffs (drops). You will have to protect the forge with refractory. I posted earlier about how to do a low budget refractory using hardpan clay, BBQ ashes, sand, and concrete. Drill some holes with a cheap drill. If you don't have one, you can often buy an old beat up one at a garage sale. Be sure to test it out. People lie. Fore the air blast, use an old hair dryer. Salvation Army sells these for $2, but you can often score a dirty one for $2 during discount days. You need charcoal to fuel the forge. I have found that Kingsford briquettes do not work well, and, besides, they cost money. Here's how to beat the Kingsford charcoal trap. Again, visit that construction site and score some wood scraps. Make sure they are not treated (green, or have little perforations in a regular array). Or, even better, clear some firewood from some busy yuppie who is in too much of a hurry to do it himself. Do not offer to pay, since these greedy bastards will often think that they are doing you a favor, and they will try to chisel some obscene favor or fee out of you. Make sure to get oak, fruitwood or pine. Do not use a toxic wood. Eventually, some yuppie will get tired of fussing with her charcoal grill and just leave it out on the street during trash hauling day. This is when you spring into action. Quietly, liberate the grill. Even if it has bent legs and rusted out vent flaps, it will be useful. Start the wood using some newspaper, twigs, and precious (bought) Kingsford charcoal. A charcoal chimney is useful for this purpose, but it costs $10. You can make your own out of a restaurant sized can, carefully extracted from a dumpster in the back of a restaurant. Discard the lid, and make sure to use a handle, since these starters get red hot when the fires gets going. Dump the flaming mass on the firewood and cook some meat. Especially good are the junk cuts like beef shoulder, since they do well with a hot start, and a dying fire. When the wood starts coaling up real good, eat the meat (hey, you gotta eat, so no fair counting this as part of the cost, besides, cheap cuts of beef are less expensive than frozen pizza). Quench the fire with water and smother it when it looks right. The black squarish lumps are charcoal, and they will produce heat that is much better than Kingsford briquettes. Plus, they are free. Use these in your forge.

I never got this to work. Probably due to lack of control, or uncertainty in brass source. I used a nut off a junk sink fixture that someone threw away. I did not melt, but I am very certain that a charcoal forge can get hot enough to melt brass. To be continued...I haven't given up on this one yet.

I have given up on the stupid big propane torch. Even with firebrick, these don't seem to get hot enough.

Reply to
Eric Chang

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