Talk to me about welding

Boosh Brus · 02-02-2017, 11:24 AM

Hi all,

I need to do some exhaust work and was thinking to try and fabricate it myself. I don't have a welder and have never welded before.

Usually I don't buy cheap tools but I cant see myself doing much welding in the future so I was thinking about getting a Ozito 120 Amp Mig welder from Bunnings along with some argon/Co2 and the relevant accessories (helmet, brush etc).

I will be welding 2.25" stainless. Is the above suitable or should I spend some more or a better machine (e.g. Cigwled inverter 185)? Should I try to learn to Tig?

Any help is appreciated.

Also, any recommendations for a good place to buy exhaust bends?

Vesper Martini · 02-02-2017, 11:36 AM

I've done a little bit of Welding years ago. was pretty good with a mig on steel
Never did any Stainless too hard...

and when it comes to Exhaust let the experienced do it, you will be forever fixing it.

**Raptor** · 02-02-2017, 12:05 PM

Not that I know very much about welding, but what I do know;

no experience + cheap equipment + stainless =

.

XRtowcar · 02-02-2017, 04:32 PM

To do the exhaust in stainless would really be better done with Tig welding, and you won't learn that fast enough to do it properly.

Junkyard-Dog · 02-02-2017, 06:12 PM

Save the money you would spend on equipment and pay somebody experienced to do it.

PooDog · 02-02-2017, 06:45 PM

I'm in the process of making a stainless exhaust for my fgx ....using a mates proper tig welder ...first attempt at tig welding and some of the welds aren't the prettiest it's similar to gas welding ? If you haven't done any welding before it would be a challenge I found the best way is to get all your cuts done nice and clean so your not filling big gaps I used a big cut off wheel fitted to a compound mitre saw so you can clamp and cut everything square

Good luck if you have a crack

ozrunner · 02-02-2017, 06:55 PM

As mentioned use the dollars to get it done properly.

If you want to do Mig welding then you need a good machine. Ozito stuff is cheap garbage. Also mig welding requires time to master as the various settings have to be precise.

You will most likely burn so many holes in your tubing it will be like swiss cheese

.

.:4:. · 02-02-2017, 07:00 PM

Maybe if you choose to do it yourself get a bootload of off cuts and practice until confident. I've had bum jobs on the welds done by exhaust shops before. Only mild steel, but none the less.

xtremerus · 02-02-2017, 07:05 PM

You will need a pipe bender as well.
I would just buy a professionally built exhaust system and be done with it.

By doing it yourself, and no experience, you will only end up with tools you say you won't use again. Probably a leaky thumping exhaust. And end up having to buying a proper one in the end.

Then again you will have more use of the tools.

There will be constant repairs needed every weekend.

hawke · 02-02-2017, 07:17 PM

There is a reason why it takes a couple of years at Tech to become a competent welder. It takes a lot of practice and knowledge.

Do yourself a favour, and pay someone competent to do it.

Perhaps look at going to night school at your latest Tech to learn? It is very difficult to learn to weld by teaching yourself.

Falcon SXR8 · 02-02-2017, 07:38 PM

Mate good on ya for wanting to have a go yourself nothing wrong with that. But I wouldn't do stainless as your first. If your keen you could do a mild steel system but by the time you buy the piping, bends, and welder you will be close to a pre done system. And trust me it takes time to get it all hanging right.

I already had a mig and some experience welding so decided to do a single system on a rodeo I have, it cost me half of a pre fabbed system but took me a good solid day and a half to get right and getting down and up a million times to do it all wears thin very quick. Would I do it again....... nope I would just buy one

marty351 · 02-02-2017, 07:56 PM

Try reading this first....

Boosh Brus · 02-02-2017, 09:00 PM

Thanks all, I could probably make it mild steel instead but I have to work out how I can couple it to the stock exhaust (possibly a slip joint but it is an odd size). I might have to get an exhaust place to rework that bit.

I would love to just buy an off the shelf system but it is a complete custom job. Its not actually that complicated, only about one and a half meters long with three bends (75, 90 and 45 degrees) and and a mount. All of which can be removed and built on the bench.

Based upon past experiences with exhaust shops and mechanics I think I would like to have a go myself. You know the old give/teach a man to fish.

PooDog · 02-02-2017, 09:42 PM

Quote:

Originally Posted by Boosh Brus

Thanks all, I could probably make it mild steel instead but I have to work out how I can couple it to the stock exhaust (possibly a slip joint but it is an odd size). I might have to get an exhaust place to rework that bit.

I would love to just buy an off the shelf system but it is a complete custom job. Its not actually that complicated, only about one and a half meters long with three bends (75, 90 and 45 degrees) and and a mount. All of which can be removed and built on the bench.

Based upon past experiences with exhaust shops and mechanics I think I would like to have a go myself. You know the old give/teach a man to fish.

If you want to do it then have a crack ....doesn't sound like to much to it , and you'll probably enjoy it ....what about doing some welding night classes ?

Boosh Brus · 02-02-2017, 09:54 PM

Thanks, I will look into courses. If I can't find one I will probably just get a whole lot of scrap and watch a lot of youtube.

madmelon · 02-02-2017, 09:55 PM

I spent 18 months in TAFE doing the most basic of TIG courses (not a trade qualification). Stainless is not easy to weld properly with a TIG, let alone MIG. If you overheat the weld pool, the weld will rust as quickly as mild steel.

After almost 4 years having not touched a welder, I decided to weld stainless flanges on a cat I bought last year. I had to practice for a couple of hours a day for a week before the welds looked average, let alone good.

With zero experience, your welds will be rubbish and probably crack fairly soon. If they don't crack, they will rust anyway. Much better off getting someone with even a bit of welding experience to do it for you.

.:4:. · 02-02-2017, 09:59 PM

Quote:

Originally Posted by Boosh Brus

Thanks, I will look into courses. If I can't find one I will probably just get a whole lot of scrap and watch a lot of youtube.

The hardest part about night courses is family commitments and work commitments. The knowledge is valuable. I've done it before with a family and a job. It makes life more interesting. Better off in the long run though

Stefan · 02-02-2017, 10:13 PM

Do a night TAFE course, I did one years ago on body resto and it was 140 bucks, and they tought you how to weld, using their equipment, and materials etc. You could bring in your own bits to repair.

Some older guys just did the course to restore / build hotrods and use the TAFE equipment and materials to make panels etc. They knew what to do so just hung around in a corner doing their own stuff.

Best way to learn how to weld IMO

.:4:. · 02-02-2017, 10:23 PM

Quote:

Originally Posted by Stefan

Do a night TAFE course, I did one years ago on body resto and it was 140 bucks, and they tought you how to weld, using their equipment, and materials etc. You could bring in your own bits to repair.

Some older guys just did the course to restore / build hotrods and use the TAFE equipment and materials to make panels etc. They knew what to do so just hung around in a corner doing their own stuff.

Best way to learn how to weld IMO

If you're in nsw and not apprentice, tafe fees are thought the roof. Just out of experience. $480 for an 8 hour course, rediculous...

QIKESP · 02-02-2017, 11:52 PM

If you want any stainless welds in piping to be half decent, welds will either need to be back purged with argon, or the back side coated with solar flux before welding.

GCRXR6 · 03-02-2017, 12:18 AM

I'm a welder, however, I wouldn't bother with an exhaust build. Really, not worth it.

simon varley · 03-02-2017, 10:34 AM

I guarantee that if you buy a fairly decent welder you will continuously find uses for it around the place.

Jack91 · 03-02-2017, 01:53 PM

I'm a welder and I find tig stainless by far the easiest process and material to weld. Also, as said for that 1.6 wall you will want to back purge. Any gaps for a newby will make you want to kill yourself. Takes a bit of expertise to fill a gap. What might be a good idea is to tack it together and get a professional to weld it for you. Or do it out of mild steel and a MIG. Be a lot easier for a newby

Jack91 · 03-02-2017, 01:56 PM

Quote:

Originally Posted by GCRXR6

I'm a welder, however, I wouldn't bother with an exhaust build. Really, not worth it.

Agreed. $300ish for a typical cat back is good value.

Pis-ton broke · 03-02-2017, 03:40 PM

i,m a welder, a very good one. there,s so much more to manufacturing a system than you have discussed. will the joints be butt welded or slip-on? you will need to buy mandrill bent bends, pipe benders wont do it. if doing in stainless you should purge the weld if it is a butt weld, cause of internal oxidization. why do it in mild steel tube? will rust out. it gets complicated, with angles and stuff.
just get a pro to do it, its a big job for a home guy.