the tig is the best.the mig is the easiest.they both need PRACTICE to use.you only need to penetrate the depth of the thinnest materiel's thickness.ie.if you have a 1/2 inch flange and a 1/16th inch piece of tubing you only need to penetrate a 1/16th at the most.i have several racecar chassis with a miller 110 volt 130 amp mig.you very rarely need to use anything any heavier than an1/8 th of an inch thick.my other welder is a linlcoln precision tig.i do all my aluminum and stainless with it aswell as chromemoly tubing for chassis that require moly.first off PRACTICE on scrap.i see so many shitty welds on this forum it is laughable.don't be in a rush,PRACTICE.a bad weld can kill you believe it or not.there is no reason to have a bad weld on your project even if you are a beginner.all it takes is PRACTICE of the proper techniques.get a book or a video and see how it is done and then PRACTICE till you get it down.if you don't and you end up with a ---- weld on your project then you are lazy and didn't PRACTICE enough or just don't care.and yes i do teach welding.to those that are interested that is.this is to everyone in general not just the op.so don't take offence .use your energy to PRACTICE not bitch me out.man i use that word PRACTICE alot. i should PRACTICE not doing that.lol did i mention you should PRACTICE.

So are you saying we should practice welding? LOL
And keep in mind that what is the most important is that it is structurally sound. I have seen welds that 'look' nice and are crappy, those are the most dangerous ones! Even if my tig welds don't always look like a perfect stack of dimes, I am usually confident that it is sound and has good penetration.

atta boy.keep at it.welds don't have to LOOK PERFECT but you also have to know what bad actually looks like.the way i see it if it looks real bad it is.don't fool yourself into denying that it is bad .bad is bad.good penetration is very important be it tig ,mig or stick.the secret is to make sure you have the machine set properly for the job at hand.that is half the battle.then ,well you know .PRACTICE.LOL if you can make it pretty you can also make it good by paying attention to the settings for heat and travel speed .you will get penetration if you follow the procedure laid out in a manuel or even by the filler material manufacturer.on the other hand if it looks like ---- and is all over the place as far as uniformity goes then it probably is ---- .9 out of ten times anyways.don't fool yourself.if you have an inclusion or an air pocket it is ---- and you will see it.make it pretty .if you can't then.well do i have to say it again! PRACTICE till you can.good luck students .any questions feel free to ask.if i can i will anwser them to the best of my ability.ps i don't stack dimes for aluminum or anything else for that matter.that is just an appearence people seem to like at the present time.i do smooth and only smooth.i don't like to be able to feel it with a finger nail.but hey i'm only human.maybe i need more PRACTICE.

damn haven't been on here in a minute. well i just finished up a 99 subaru legacy turbo build. i went and got myself a lincoln pro mig 140, some 309 wire and tri mix gas. i fabricated a 3" exhaust as well as 2" intercooler piping for the car in 16 gauge 304ss. i used 309 wire because the exhaust was actually made from cut up pieces from two different exhausts, one ss and the other mild steel. i didnt have to weld any pipes to flanges, but for what i used it for, it worked out beautifully. not sure if you guys are interested, but i can post up pics and vids of the build. used an ej20g (jdm wrx turbo motor from early 90's wrx), usdm wrx 5 speed transmission and rear lsd swap, 04 usdm sti suspension, wrx td04-13t turbo, stealth black fmic, 3" catless turboback exhaust (straight pipe, with only a melon shooter muffler), and a megasquirt 3 setup for full sequential with wrx coilpacks and sti injectors. pushed the turbo to the max and it gets up and goes pretty nicely. hoping to upgrade to a 20g at least soon ;-)

post up the pics!

yea lets see the pics.

nice I wanna see the car too