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Dy_
28-06-2009, 04:14 PM
has anyone here got any tips for a first time welder?

i've got an arc welder at home and would like to know any tips you guys might have.

Job: about 2-3mm steel [exhaust pipes]


thanks!

DLO01
28-06-2009, 05:12 PM
Do a tafe course. :thumbsup:

SHOGUNOVDDRK
28-06-2009, 05:16 PM
I'm planning to do a tafe course in the next few weeks, I agree with the above.

Danny, if you need something welded a mate of mine is a boiler maker by trade and could do it for you.

Send me a Pm if you want him to do it for ya (won't want much, maybe chuck him a few bucks or a beer or something?)

TODA AU
28-06-2009, 08:57 PM
Good luck....
Stick welding exhaust pipes would suck & propably end up looking like shit.
(Especially if done by a 1st timer)

Better off using a MIG or TIG...
If you're going to persist...
Get a really good welding helmet so you don't get flashed,
& practice heaps on stuff you don't need before you cost yourself more than you would if you pay someone else to do the job...
& if the parts are attached to the car...
Ge a surge protector or remove the ECU

JohnL
28-06-2009, 08:58 PM
Get some scrap and practice, a lot. I would suggest not even thinking about arc welding with the parts still atttached to the car.

eg5civic
28-06-2009, 09:06 PM
i wouldnt arc weld an exhaust mate
i just did my block of it for my apprenticeship (fitting and turning) and trust me its not as easy as it looks, welds can be neat but take alot of time and a steady hand,
I did about 8 hours of it and was getting the hang of it, started with weld beads, then pads of weld, then building it up, then i did a T fillet, corner and lap joints and finally a butt weld

IHMO as the boys said do a tafe course, but if i were you money would be more wisely spent on someone doing it for you

82911
28-06-2009, 09:25 PM
As has been said above, ARC welding (unless it is shielded arc) is best left for heavy construction,or out door work where it is not practical to use MIG or TIG.
Most exhaust tubing should be about 1.6mm thick mild steel, so even an experienced stick welder will struggle to keep the weld pool under control.

eg5civic
28-06-2009, 09:57 PM
As has been said above, ARC welding (unless it is shielded arc) is best left for heavy construction,or out door work where it is not practical to use MIG or TIG.
Most exhaust tubing should be about 1.6mm thick mild steel, so even an experienced stick welder will struggle to keep the weld pool under control.

Nail on the head!

As said above, 1.6mm steel is hard to arc weld, and very easy to burn though it, i knw i melted the corner of my T fillet in 1.6 just trying to tack it

Dy_
28-06-2009, 10:02 PM
yeah i was just practicing some weld beads earlier...wasnt too bad.

My bpipe etc are off the car just need to cut and joint a few spots for the install. Basically i cant get my hands on a cig or tig welder. I'm willing to pay for an exhaust shop to do it but i want to learn it for myself.

Also not too fussed on the weld spots being neat. Just scared of putting holes in the pipe lol. although i tried hard to put a hole in some random 3mm thick steal and couldnt do it? is it easy to put a hole in it?

thanks everyone

vtesh
28-06-2009, 10:15 PM
how long does the course go for?

JohnL
29-06-2009, 11:30 AM
Most exhaust tubing should be about 1.6mm thick mild steel, so even an experienced stick welder will struggle to keep the weld pool under control.

It can be done, but 'arc' isn't the technique of choice for such thin steel (especially plated, which tends to cause the stick to 'stick' to the job). MIG,TIG or oxy-acetyline would be far easier and likely to give better results.

To do it with an arc / stick welder you will need to more or less do it as a series of 'spot' welds, each 'spot' overlapping the last. To do this successfully takes patience since after each 'spot' you need to stop and wait for the metal to cool off enough that the next 'spot' doesn't blow a hole.

Oh, and the metal will need to be clean...

Dy_
29-06-2009, 01:13 PM
It can be done, but 'arc' isn't the technique of choice for such thin steel (especially plated, which tends to cause the stick to 'stick' to the job). MIG,TIG or oxy-acetyline would be far easier and likely to give better results.

To do it with an arc / stick welder you will need to more or less do it as a series of 'spot' welds, each 'spot' overlapping the last. To do this successfully takes patience since after each 'spot' you need to stop and wait for the metal to cool off enough that the next 'spot' doesn't blow a hole.

Oh, and the metal will need to be clean...

john, what do you mean by spot welds?
Also i have noticed while practicing that the stick does tend to stick to the job...is there a way to prevent it?

hisoka
29-06-2009, 01:47 PM
Good luck....
Stick welding exhaust pipes would suck & propably end up looking like shit.
(Especially if done by a 1st timer)

Better off using a MIG or TIG...
If you're going to persist...
Get a really good welding helmet so you don't get flashed,
& practice heaps on stuff you don't need before you cost yourself more than you would if you pay someone else to do the job...
& if the parts are attached to the car...
Ge a surge protector or remove the ECU

correct and correct.

i was laughing, till i read this. no one even told him stick welding a exhaust was stupid.

as they said do a tafe course. if you know any boiler makers they can usally have it done in like 10 minutes, if its just a cannon being welded on.

not easy stuff. i did a radiator support once and holy shit that was a disaster.

joyride
29-06-2009, 04:40 PM
i might hi-jack this thread a little... TIG or MIG when spot welding a chassis? seems like its a personal preference for most welders...

82911
29-06-2009, 06:49 PM
MIG will do a better job of burning through the crap that hides in the seams. So I use MIG for seam welding jobs.

JohnL
30-06-2009, 08:31 AM
john, what do you mean by spot welds?

Not 'real' spot welds (as you find in car body seams, made with a resistance welder), but each 'spot' being a very short arc 'run'. These 'runs' are so short that each one looks like a small circle, and each circle overlaps the previous circle, forming a chain of overlapping circles. When done well the overall weld can look very nice, but it's slow to do and can end up looking messy if you rush it or lack the knack.

The reason to do overlapping 'spots' is that between doing each 'spot' you can stop to allow the heat from the last 'spot' to conduct away from the weld site into the rest of the sheet / tube (where it dissipates).


Also i have noticed while practicing that the stick does tend to stick to the job...is there a way to prevent it?

A few things:

Aquire the knack of not letting it stick (which is a 'touch' thing that I'm still trying to properly master after 30 years).

Get the amperage right.

Make sure the steel is clean.

Grind / sand off the zinc plating where you are going to weld (this will also most probably result in a better weld with less porosity).

Use a stick / rod that tends to 'stick' less than other rods. I would suggest the 'Satincraft' rods (and similar from other manufacturers) as an easy(er) to use rod that gives good looking and ductile welds.

Some rods are harder to use / strike arc with than other rods, but give welds of a specific strength qualty. 'Easy to use' rods (such as 'Satincraft' and similar) tend to give softer welds that are less suitable for high structural loadings (you wouldn't build a boiler or a train undercarriage etc with them), but if you were forced to arc weld an exhaust would probably be the (type of) rod of choice.

Practice, practice....practice...............

For welding thin steel use a thin rod (I think 2.5mm is the smallest diamater).

My experience is that one of the hardest things when learning to arc weld is learning how to look through the arc and at the weld puddle (instead of looking at the arc). Once you get this it becomes a lot easier.

Bludger
01-07-2009, 12:30 PM
i might hi-jack this thread a little... TIG or MIG when spot welding a chassis? seems like its a personal preference for most welders...I think TIG is more delicate than MIG

Dy_
01-07-2009, 01:19 PM
thanks for all the tips and comments people.
I've decided not to tackle my exhaust yet, but will be spending alot of time just practicing with random think and thin materials and see how i go.

ekdez
01-07-2009, 04:20 PM
& if the parts are attached to the car...
Ge a surge protector or remove the ECU

so.. in theory you shouldn't weld to the chassis? even its just a hanger?

DLO01
01-07-2009, 06:54 PM
so.. in theory you shouldn't weld to the chassis? even its just a hanger?

If its an metal connetion to chassis and its an electric welder then no. Oxy Acetylene no problems.

JohnL
02-07-2009, 05:54 PM
My understanding is that it's OK to arc weld a chassis so long as the battery has been isolated (disconnect the earth terminal), and I've done it numerous times with no problems. This is no guarantee that the electronics will never ever get fried...