mig or arc?

[flames]

hello all.
i am in the process of chopping a motorbike,at the moment,and for a while yet,all i am doing is cutting,preping and tacking to frame,then taking it to work for someone who knows what they are doing to weld up.one bit i shall be modifying in the near future,is the rear axle plates on the swingarm.i am pretty sure these will be hardened steel because of the job they do.what i intend doing is cutting a piece off a pair of axle plates and welding them atop the axle plates on the swingarm i shall be using.as i said i guess they will be hardened.one set of plates are 8mm thick,the set to be welded atop are 9 or 10mm thick.for tacking purposes i have a sip 140 weldmate arc welder,and a blue(lol) 150/1 turbo mig,which i am yet to use.i am guessing arc would be best for tacking,especially as its the only one ive used.but outta curiosity,wd the mig b up to tacking such thick metal? or wd it compromise the finishing weld when matey welds over it later? also when i take it to work,wd it be best to get him to arc weld it or mig? i cdnt tell u what make etc of arc and mig welders they have at work,but it is deffo serious kit and nuffin like the cheap and nasty hobby jobbies i got.

 

[GeorgeB]

nuffin like the cheap and nasty hobby jobbies i got.

If you rate your gear as so bad, why are you even thinking about using it on structural repairs (even just tacking)?

 

[Drains]

Flames, your mig will be fine for tacking, but if your mate is doing the job properly he'll grind the tacks off as he goes so the real weld will be consistent quality.

Mig is easier for tacking than stick, though always, you must make sure yo're getting good fusion (use a small diameter wire - 0.6mm). For the final weld mig also puts in less heat than stick for the same size weld, so you should expect less distortion of the finished frame.

 

[flames]

cheers chaps.george,i dont really think its cheap and nasty,just nuffin like they have at work.its fine for a novice like me to learn on.the reason i need to tack is coz they aint really sposed to do my welding at work.so i get it all ready,shaped n cleaned and tack it up,which i have been using my arc for till now,sneak it into the workshop then all matey has to do is zip thro it with the mig and then i smuggle it outa the way rite kwik.i dont think its a big no no,but its a big mill,and very unpersonal coz of the number of staff there.if i ask if its ok,prob get told no,coz if we say yes to you,we gota say yes to evryone else.thats usually how it works anyway.

 

[GeorgeB]

cheers chaps.george,i dont really think its cheap and nasty,just nuffin like they have at work.

That's a fair statement and I agree with you now but it's the opposite of what you said before. Low priced gear gets too much bad press. Good luck with whatever you decide to do.