RealQuick

iTrader: (14)

What are you guys doing for back purging your stainless pipes?

Are you just using tape? Anyone build end caps that have a hose fitting on them that slide over the pipes? I am just trying to figure out how everyone does it.

Pics would be cool.

BigRich954RR

iTrader: (1)

Why are you looking to back purge stainless pipe what are you building ?
your using tig right ?

RealQuick

iTrader: (14)

Sorry for the lack of details! Yeah, tig welding 304 SS. I have some headers I tacked together using the mig, and I want to tig them up, so I am trying to figure out the best way to back purge. I have a second line I can use for the back purge, but how are you guys keeping it in the pipe? Using welding tape on both ends and sticking the hose in one of the ends?

Tig

I use the blue painters tape. I also have 2 rubber hose ends/caps that I use for doing exhausts.
Dont forget to wrap the joints that havent been welded and have an exhaust hole to, at least for your finish bead.

RealQuick

iTrader: (14)

when building primary tubes on headers, alot of the welds areas are close to the edge of the pipe... so blue painters tape that I have tried actually catches on fire. I am gonna try aluminum tape.

Silverback

Usually painter's tape, but I've also used expanding plumbing pipe plugs (the ones with the rubber seal and the wing nut to tighten it).

RealQuick

iTrader: (14)

I'd like to try this! Home depot or Lowe's probably carry them.

Tig

You beat me to it, lol.
That was going to be my next suggestion.

99345hp

aluminum foil with a hose clamp works very well also

Davo346

iTrader: (1)

why not use solar flux to keep the weld from sugaring ,and another thing you use less gas that way,anyway on something that thin you dont need a gap

BADD SS

iTrader: (4)

Solar flux is a pita compared to back purging, it's really not a big deal at all. Aluminum foil and a hose clamp.... done.

Davo346

iTrader: (1)

all im saying is on something that thin there will be no gap so there will be no need in back purging,i thought you should back purge on a open gap and solar flux is used on closed gap . and another thing what is pita,all i know what pita is ,is a type of bread.not being a smart *** just inform me please.and if you mean a pain in the ***,all you do is brush it on thats it.

Tig

Yes PITA = pain in the ****

Even with no gap you can still get sugar if you're using too much heat. Purging allows you to use that little extra heat to creat a perfect weld inside and out.
Yes solar flux may be as easy as brushing on but it does not create the same weld as purging......

Whistler

iTrader: (46)

I use plain old duct tape unless the spot I'm welding is close enough to melt the glue. At that point I'll put forth enough effort to tin foil and clamp

Davo346

iTrader: (1)

not to sound like dumbass or smart *** but why is solar flux used please inform me.

mgroshong

Solar flux's name implies what is does. It creates a protective barrier to prevent oxygen from polluting the back side of the weld (surgering). the results are similer to back purging and can be more cost affective if your able to use it over a full argon purge.

For instance if i was welding a turbo header where i would run the risk of a chunk of the solar flux breaking off after the welding process and being ingested by the turbo then i would use a common argon purge so this is avoided.

Now if i was welding a large volume exhaust system or similar large volume system where there was no risk of damaging something down stream. Then i could use solar flux to reduce argon cost/usage.

Hope that explained it for you.

Tig

You're not sounding like a dumbass or a smart ***.

Its more for the DIYer, its cheap.
I have not heard or seen of any shop using solar flux (exhaust or pharmaceutical grade SS tubing and pipe) Comparing it to an argon purge, its just not as efficient.

mg put it in better terms, well said.

Davo346

iTrader: (1)

so before the turbo no,after the turbo yes on solar flux.very good point.so if no turbo is present solar flux would be the way to go.and really i was being a little sarcastic when i said why is solar flux used,you actually get the same weld with solar flux,its a fact.

mgroshong

sigh, good thing i typed that all out.

Davo346

iTrader: (1)

you make a very good point.the other sh.. was intended for tig.for saying solar flux doesnt create the same weld.