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Hi guys,

I have found the only thing within my budget atm is a stick welder, lol.

I have experimented welding exhaust pipe, specifically 76mm OD 1.6mm thick on low amperage with 2.5mm sticks.

Does anyone have some tips I should consider when trying to weld the flanges (8mm) to the ends of the 1.6mm thick pipe?

What methods do people use when it comes to forming elbows and bends in pipe, without the use of pipe bender (Cutting angles)?

How about determining the radius or mapping of a curve of exhaust pipe under axles and through the chassis exhaust tunnels .etc? - Maybe I should make a seperate thread :P

I find drawing a scale diagram with measurements, deriving the angles and measurements fromt the drawing and then cutting the pipe to the chosen size/ angle etc.

Would be very greatful for some replies.

Thanks.

your gonna have trouble, by the time you've got enough power/heat to melt the rod, its gonna destroy 1.6mm steel, ideally you'd tig weld it. get to your nearest blackwoods, they've got tig torches on speacial atm for like $63, disposable bottle of gas is like $30, add in some tungsten/filler rods and your TIG ready for under $100. if you cant tig weld learn quick :P

lobster back bends, although most people will tell you its a waste when you add up all the time it takes, and cost of your consumables, when you can buy bends for like $20.

as for where to run the pipe, maybe just tack it piece by piece and see how you go? lol dont know how else

Edited by VB-

you can do it however you will need to focus the heat into the flange instead of the pipe its quite easy to do if you know wat your doin however it'll be alot easier with a mig or tig.. however same thing.. you will need to focus the main head onto the flange and let it roll over and fuse into the pipe so basically... instead of havin the rod like this to the join... /|\ angle it more towards the flange if you get wat i mean.. when i make it home ill make up a shitty paint drawing to explain wat i mean

There are mig welders on ebay for around $200. Trying to do an exhaust with a stick welder and lobster bends will end up in tears. Once you blow a hole in the pipe(which will happen frequently) It is almost impossible to fill it, and the hole will get bigger and bigger.

you can do it with a stick welder but as said above its a flamin mongrel of a job and most times you will burn holes. When it comes to welding the pipe onto the flange just make sure that most of the heat is on the flange as its thicker and want burn holes. I just used the stick the other day to fix 3 holes and a seam of a muffler on a bogan vn wagon. I found it easier to turn the heat up a bit and just move my stick a bit faster. If you do burn holes its not much of a prob as they can be filled in pretty easy just let it cool down a bit each time you fill apart of a hole and dont attempt to fix it in one go or it will just get bigger and bigger and bigger.

If you keep blowing holes in the pipe just walk away and have a beer break :P

I've found that if you can get heat into the flange before you weld, the easier it will be. If you have a blow torch, get it nicve and red before you start. If not, sticking it in the oven (I know it sounds odd) also helps.

Just buy the bends as for the tig grab a hand peice and put them opposite to arc so change from dc+ (arc) to dc- and your good to go stainless and mild steel you need ac for alli work

  • 3 weeks later...

f**kin hell

this case isnt too bad since your doing it yourself

BUT IM SICK OF f**kING HEARING PEOPEL PAYING HUGE AMOUNTS OF MONEY FOR A "CUSTOM" EXHAUST

where they mig/stick the shit on

PENNNOO!!!!!!

if u want a nice exhaust/cooler piping any airflow pipe

PURGE WELDING

we do it flat out at work, its the f*kn shit

unfortunatly im not that great at it yet being an apprentice

:D

f**kin hell

this case isnt too bad since your doing it yourself

BUT IM SICK OF f**kING HEARING PEOPEL PAYING HUGE AMOUNTS OF MONEY FOR A "CUSTOM" EXHAUST

where they mig/stick the shit on

PENNNOO!!!!!!

if u want a nice exhaust/cooler piping any airflow pipe

PURGE WELDING

we do it flat out at work, its the f*kn shit

unfortunatly im not that great at it yet being an apprentice

:)

purging is great however its not cost efective for exhaust systems in my opinion but yes i agree.. im sick of seeing all these exhausts migd up.. especially when the f**kheads use mild wire on SS

To be perfectly honest, i dont see purge welding as being necessary on a car, especially not the exhaust. How much power gain would you expect to see if an exhaust is purge welded as opposed to mig welded. The weld wont be particularly stronger, and it really makes no difference as the exhaust strength isnt crucial. Ive never seen a "custom" exhaust from a shop where a stick welder has been used. I just cant see the market for a purged exhaust.

^ X2.

for a shop, why waste the time to TIG it when you just give it a quick zap round the outside. wont effect performance, durability shouldnt be effected too much (almost nothing when you consider how long people keep there cars for)

now look at how much money they would lose if they did TIG it, every weld would take twice as long (I'm being generous here), you would use twice the gas, more power (higher elec bill) etc. its measurable on one exhuast, so think about how much it would add up over time if all you did was exhaust work

also left out the bit about TIG welders getting payed more than MIG welders (not always but as a general rule they do), but you get the idea

To be perfectly honest, i dont see purge welding as being necessary on a car, especially not the exhaust. How much power gain would you expect to see if an exhaust is purge welded as opposed to mig welded. The weld wont be particularly stronger, and it really makes no difference as the exhaust strength isnt crucial. Ive never seen a "custom" exhaust from a shop where a stick welder has been used. I just cant see the market for a purged exhaust.

my point exactly

costs them moe for quality work

im the customer not the business owner

exhausts i guess u can be a bit easy

but intake pipes etc

definatly purge

my point exactly

costs them moe for quality work

im the customer not the business owner

exhausts i guess u can be a bit easy

but intake pipes etc

definatly purge

you dont need to purge intake pipes and intercooler pipes to get smooth joins inside.. you just need someone who knows wat there doin with a tig and you can fuse the join with little to no penetration at all and it still has plenty of strength and will not leak which i why i fuse everything excelt pipe to flanges on exhausts

purging is not needed in any pipework for the automotive industry

HORSE SHIT If you want a half ass job don't purge, but if you wan't a GOOD job purge it the extra gas is f*#k all about 5l per min is all that's needed.

And to say a fused weld is as stong as one that has full penetration is a load of shit you can go on the way you wan't but I will alway's purge any stainless tube/pipe I weld nuff said

HORSE SHIT If you want a half ass job don't purge, but if you wan't a GOOD job purge it the extra gas is f*#k all about 5l per min is all that's needed.

And to say a fused weld is as stong as one that has full penetration is a load of shit you can go on the way you wan't but I will alway's purge any stainless tube/pipe I weld nuff said

im not saying a fused weld has as much strength as a full peno'd weld however wat i am saying is there is no need in exhaust work or intercooler/intake piping as all its doin directing air.. how much bloody load do you think these pipes get put under i have no had one single problem with any of the piping ive done which has been fused. no cracks leaks or anything.

The only time Ive been instructed to tig purge weld is when i work on food grade equipment, I've welded pipes on ships that require Lloyds inspection and approval and didnt need a purge for any of them, I was also taught 2 ways to weld pipe for a 1st class weld, for purge lots of penatration with the torch at 70-80 deg to the weld, for no purge hold the torch around 10-20 pointing back so the blob also forms inside and is bathed by the argon, if done correctly (professionally) it will be as strong and long lasting as a purge.

At work I use 1.5mm stainless rods (yes they exist) to weld thin stuff, I prefer them to TIG as its quicker and gives just a good as finish, but for exhaust systems I think mig would be the most cost effective for a shop and just as good as tig/stick for what they are doing, I cant see steel wire being all that good from a rust point of view but it works ok with stainless, for a good finsh you cant beat TIG though.

All exhaust I make are purged, I use 0.8 filler and sometimes go for a helium/argon (20%) mix for better pen on low amp's.

Trust me for racing applications it's needed you get alot of vibrations and extra stress on the exhaust. I'm just a bit more fussy about how I go about my work, always take the hard way and make it bullet proof that's what I'll be doing to my exhaust down the track but hey that's just me

I would say thet the 0.5% of customers who would be happy to pay the extra for a purged exhaust system, all of them wouldnt want it done in stainless, when inconel or titanium are available.

And Im sure they woulnt be intrested in paying extra for inconel or titanium as well as the extra cost of welding in a atmosphere of inert gas it also depends on the application (race or street) I know we cant use either of the alloys in our cat of racing, but when you look at the cost of a full race spec exhaust (around $16,000 is what it cost for us) that small amount of extra gas used for purgeing is neither here or there.

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