Welding Tips and Tricks

Basically I'm just wondering what you guys do with your thinner pipes, i understand that when using thick walled pipe especially for something like a exhaust manifold you would grind back the edges for more penetration but when fitting up the rest of the exhaust or even intercooler piping do you guys just butt it up and weld away?

I just assumed because there is not as much heat/Mechanical load on the parts they would be fine. Being round as well i would imagine intake piping under boost would evenly distribute pressure unlike say a intercooler end tank or a intake manifold with flat areas.

Does this sound right?

Butt it up tight & good fit.

Whenever possible I use a short backing ring & gap the joint - some car / bike guys may worry about flow & comment but I yet to see any negative effects - I will add that I do more truck / tractor / earthmoving things than NHRA ! so strength / durability is more important than any horsepower claims - it also gives us old guys with failing eyesight something to aim for when welding - I hate tightly fitted butt joints as I just lose the darn line when welding.

I did a motorcycle exhaust and just butt it up, tack it on the top and then make sure its straight, tack it in the bottom, if its thin, I fuse, thick I weld it with a small gap.