Manifold fabrication opinion
Turbo Mini Forums

Hey, i've got so far in fabricating a manifold and would like some input before i finish welding, in the picture i need to weld beween the lines, would i be better to

A - As per the left one, just weld it and leave it alone

or

B- Weld it without filler, then weld a band over the top as per the right hand one?

My thinking is that with B, there will be less penetration inside and so smoother, and theres also the added strength, but is that an issue for these? Or would A provide enough strength? Also i want it to look half decent so i'd rather avoid a big weld!

Thanks :)

If you are using the TIG and it's a tight gap all round, just blend it in.

If it is a decent full penetration weld then it should be strong enough. I would not just fuse the area together without filler as this will leave it thinner and vuerable to crack in this area.

If you back purge the weld area with argon, it will keep it clean inside.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

So basically ditch the band idea, i'll be TIG'ing it so just run it in (with filler!) and leave it alone and all will be well? I did the same on the downpipe/turbo outlet but as this is so close to the ports i thought keeping it smooth was key!

Paul S, thanks for the tip on back purging, i think i'll just TIG it normally, mainly due to the effort in setting up a decent back purging set-up! Rather than essentially a roll of tape and an argon cylinder...

Thanks all, any more comments please let me know :)

It really is worth the effort to back purge. If I want to do something quickly I stick my MIG torch inside and tape the trigger down whilst I weld round the outside as a quick and dirty solution.

I have a tee and a valve connected in the gas supply to the tig.

Connect the pipe to a flange.

Edited by Paul S on 17th Jun, 2010.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Can i use argoshield to back purge, or does it have to be pureshield? I'm now thinking i could just set-up another cylinder with a regulator and pipe straight into one of the flanges, if that would work? (mainly as i don't have the tee and i was going to do it tomorow!)

I was going to have the manifold bolted to an old head whilst welding to stop it warping, but if i have pipe in a flange i can't have one fitted, will that matter too much?

Tom, i do like that idea, but unfortunately the MIG's are downstairs and TIG's are upstairs :(

Cheers

Edited by Amp on 17th Jun, 2010.

Any gas that keeps out oxygen will do.

Feed the pipe through the head and block off most of the other flanges to keep the gas in.

If you don't bolt the flanges down, they will warp.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

I'll do it properly and go and buy the right tee piece and just weld it next week, thanks very much!