Welding fundamentals

I am new to welding. Whilst fixing things around the house I occasionally run into need to weld stuff - broken pipe, joining stuff and cutting stuff.

What kind of equipment I should ben looking for? I'd like to buy versatile equipment. My first task is to fix a leaking copper pipe. Allthough I could use other tools I am sure welding equip will come handy later.

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I would suggest the portable oxy-acetylene setups available at your local big box store for under $300. They come with everything you need to get going, and they really are easy to learn to use for just this type of work. People have been welding with this approach for many years, and some very complex and demanding projects, so you can learn a lot and get a lot done with this setup. Later on, if you do move to other equipment, you will still use this for cutting and brazing, so your investment is still useful.

If you just want to get the copper work done, an inexpensive plumbers torch and some plumbers solder will do the trick for under $20. I have made a bunch of fun metal art using just that and scrap copper, so I am a big fan of simplicity...

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Thanks for the tips. I looked at some of the torches you mentioned, but I see future use as well.

What about TIG welding? Can it be used for multitude of task and fixing my copper pipe.

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Jimmy Neutron

Leaking copper pipes are not normally fixed by welding them. Whatever is leaking, is cut out and a new piece of pipe is sweated in. Check out alt.home.repair if you need to do such plumbing repairs.

For arc welding, TIG welders offer possibility of both TIG and stick welding and can do almost anything. A used TIG welder can be bought for not too much.

Stick around and read this newsgroup for a while, talk to people etc before making a buying decision.

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John, here's what you do to fix a leak in the middle of a run of copper water pipe. First, figure out what size pipe it is. Let's assume it's 3/4". Then, go to the hardware store and get a 3/4" butt union, the kind WITHOUT the little flange in the middle. This kind slips right over a pipe and can be located where you need it. Get a torch, some solder, some flux and some steel wool.

Drain the water from the pipe. Take the steel wool and polish the bejesus out of the leak area, back an inch or two either side of it. Take a hacksaw or tubing cutter and cut the pipe at the leak. Slip the fitting up the pipe. Flux the area. Realign the other end and slip the fitting over the new joint. Heat with torch and apply solder. When soldered, the leak will be fixed.

You don't need or want a welder for this job.

If you want to spend money on a welder, I completely and thoroughly approve. I suggest the Miller Dynasty series. They will meet your requirement. They do cost about as much as a new Harley Davidson, but for a guy like you, that's nothing.

Buying a TIG welder to fix a copper pipe leak? Man, have you found the right newsgroup!


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Grant Erwin


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David Todtman

For most general home welding jobs a small MIG set would be ideal, and it is pretty easy to learn and cheap to buy.


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Very true , but stick welding will give you understanding in another area thats different .

Start with 6011 ( Lincoln Fleetweld stinks and splatters and will not make a strong weld ) Alloy rods corp and others make good rod . 6011 is good cause it shows you the puddle ,

6013 et al will cover the puddle with crap . You can put 2 separate beads on a close spaced work piece with 6013 ! And the embedded flux cant be heated out . It takes alot of heat with a 6011 to force out the 6013 flux ( 6013 is sim to 7014/7024). 6011 is the deepest penetration, and the widest heat range of any rod . So you simply turn down the heat and weld .020" sheet metal with 1/8" rod . Alloy rods corp 6011 is much quieter .

Next is MIG , but mig is shallow penetration and if you dont burn a hole at first , you'll prbably pile up filler til it looks bad . Penetration is the only way to get good welds and so you must use a large wire on thin work so the voltage is not dropped in the wire . But MIG is the most fun for the speed and it doesnt splatter your helmet , arc is softer . CO2 is cheap at beverage suppliers and makes perfect welds in steel . No cleanup at all . 75 lb cyl is abt $25 . but it weighs >230 lbs full !! But i use it to fill small 20lb bottles . As long as the temp is above 86 F , you can not over fill a cylinder , cause there is NO liquid , only a super hvy gas . You will feel a cold spot low on the tank , below 86 F , but above 86F the gas conducts heat so fast the whole tank is at same temp . Its amasing how little CO2 flow you need if you are indoors . MIG needs not continous variable heat , only a few settings will do . Its the wire speed that will mess you up . Start with too much speed , then adjust it lower as it "nudges" you . Always use the biggest wire you can . I will use .035 solid on .040" sheet metal . It is stronger weld , but you must move fast and precisely !

MIG is easy . In 1986 i got my first MIG , after welding for many years . I laid down a bead w/o a helmet ( closed eyes ) on .040 " sheet metal . the other side had a "bead" !! By using spot , you can make better spot welds than the HF 230vac spot welder ( i have 2 ) a copper plate abt .06" behind as a backup .. But you need SCRs on input or output to controll the spot time ... I just ordrd some PC power supplies , 450 WATT . I will parallel them to a cheap MIG and get 120 amps 100% . Then when i get time , i'll toss the HarborFright MIG power supply that it came with and use all PC P.S.'s . 120 amps is about right for most jobs . If you want 1/4" plate , you will need the longer "250" copper tips ( has diff thread ! small MIG uses 1X6mm , larger uses 1/4" 28 !!) .... and 250 amp MIG box .

BTW Cent GS155 ? had a bad design transformer , stay away from it . The New HF $450 MIG uses a toroid ( better ) and has no spot/stitch . But i like their idea of split rollers for wire drive . The rollers are 2 halves , they pinch the wire from 2 sides while the ballbearing pinches on the 3rd surface . If you could put a high capacity fan directly over the toroid , you could get more weld time . Its at 15% on 200 amps range . just put a cheap diode or LM34DZ on the toroid to shut down on over temp . Its the copper wire that need thecooling air .

MIG and stick are "production" welding , TIG is NOT ...

Emmo wrote:

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TIG dont teach anything useful , fast . Fullfillment comes from learning a easy way and seeing all the use it can be put to .

If you like to create in metal , stick weld first for low cost , then MIG . MIG is low cost and can create faster than any other . Its so fast and productive , they call it a "production" welding method . TIG is not , nor is gas welding .

Like TIG on Aluminum . Its difficult to learn for the quickness required in safeing the Tungsten as you apply filler rod . Thats why you always see good welds are little separate beads . The weldor quickly retracts the torch , or if he was slow , you hear him curse and stop welding and go to the grinder to clean his Tungsten .

91% Tun 9% Zinc soldering is a big surprize , it works ! You dont have the problem of cleaning off the Al oxide , just scratch the solder in with a brush and apply a bit more filler rod . Its strong .

But aluminum welding is not a cost effective factory method of making stuff . It has too many "competitors" that beat it out .

Just a last thought on MIG ... CO2 will provide perfect wleds and set the wire speed higher than needed , then back it down slower til you are not pushed out , as you weld . This prevents a large gap , and lost heat . The wire is so small , it has trouble delivering amps to the work piece , so you must use the largest wire and the fastest speed you can and move fast to get penetration . Fast , for if you weld slow , the heat WILL build , but theres a thick layer of wire built up , so you can't improve the penetration ! Its too late . But it helps to preheat thicker MIG work pieces . Theres many things they wont experiment with , today . Why cant i cut with MIG ? Preheat with arc , apply MIG ( to thin work only ) , and quickly make cuts , but the edge will not be sharp as Plasma or others

Imagination works ! Tiny copper washers , swedged around a 0.030 plug gage . Stack them in your torch . Beats tossing tips , for you can quickly renew the washers as often as you like .

Another tip . Dont save old MIG wire , even tiny corrosion will make trouble . Make a box charged with a bit of CO2 to keep out the air . CO2 is far heavier than air . And if you cover the work well , you can turn down the gas to almost nothing . 2 psi thru a long plastic line !

Dont buy a MIG with a gas solenoid , its not needed .

And a copper block behind the thin work will let you start up without burning holes , also used for spot welding , but your box must have a electronic heat control , not steps .

I get some PC power supplies next week , ill mod them to power MIG welder . They are 100% . 150 amps . 60 minutes welding in each hour . The 5 vdc winding is usually center tapped and they use only one side . Ill full wave rectify the whole winding and get 12vdc at same amps ( 35 amps each supply ) PC power supplies can be safely series'd or paralleled to make any combination you like .

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Must have:

Stick welder MIG welder TIG welder Acetylene brazing/welding torch Acetylene cutting torch Chop saw and/or band saw Big vise Welding table Bench grinder

That's just a partial list that includes most of the equipment you need to occasionally fix copper pipe and/or take part in this newsgroup.


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The list continues:

Magnetic positioning clamps, sliding C clamps Several angle grinders - some with wire brushes and others with grinding wheels Speedglas welding helmet, leather jacket, steel-toed boots Silver solder, lead-free solder, acid flux Pickup truck and trailer to haul metal around

10# box of 6011, 6013, 7018 electrodes 200 amp breaker box >John wrote:
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Tom Kendrick

You forgot welding rod ovens, fancy safety glasses, several pairs of Tillman welding gloves and about 40 clamps of various kinds. Also you'll need many more welding cylinders than just oxygen and acetylene! You'll need helium, argon, C25, CO2, and propane as a minimum, along with a mixing manifold to make up your own mixes as needed, along with several regulators & flowmeters. Oh, and then there's the fume extractor. Not to mention the CNC plasma table! Overhead rolling crane is very handy to.

All in all I'd say about $45kUSD should get you started.


Tom Kendrick wrote:

Reply to
Grant Erwin

you forgot the 40x40 shop with 3 phase power and the shop assistant who likes to sweep floors.

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