MIG beginner - zorst?

[skell]

The 'custom' exhaust made to fit my AAZ(or similar, still not sure what the lump is) just bust, so as I was getting around to buying a mig welder I've just ordered one. I figured the exhaust would be a good first job as it is not structural and not visible, what do the experienced welders on here reckon - is this going to be a sensible job for a beginner or should I phone a friend?

[andysimpson]

Just have a practice on some scrap metal (a bay or splitt will do) and play with settings on the mig/gas too see the effect it has. If the exhaust has rust through you will have fun as a beginner especially if its a cheaper mig. If its fractured it should be easy to do.

[skell]

thanks Andy
I've ordered a new down pipe to chop up so rust shouldn't be a problem, just won't be in keeping with the rest of the bus!

[kevtherev]

Just have a practice on some scrap metal (a bay or splitt will do)

*snigger*

["WEAZLECHIN"]

what mig is it? and what is the minimum amps rating it will work at?
oh and if you are a "biginner" biginner get an auto darkening head mask and if its a gas welder dont try to weld outside with a breeze blowing, you will only get rather annoyed !!!!!!!!

[Andy syncro-nutz]

high voltage = high speed wire feed, low voltage = slow wire speed, mid voltage = mid wire speed. Clean bare metal for good contact and good weld! When you get a good weld you will hear it buy a destinct crakling sound crisp and clear! Stick to still overlapping spots, Short bursts of the trigger! ((((((((((((((O Like so!!

[hammy44]

i have one of those auto darkin masks but when it darkens i cant see the welding even on the lighter setting. maybe i need glasses

["WEAZLECHIN"]

i only paid £26 for mine. best thing ever.. on target every time!!

[chickenkoop]

auto react helmets, start with your settings, put it all on the lightest/lowest settings, you should be able to see clearly through the lens at the job, spark up and the lens should darken,then clear, you will have to play with helmet settings to get them right, shade,sensitivity,delay,use a scrap piece of metal, check the delay if the screen stays dark,hope this helps,

[skell]

I've ordered Clarke 135TE, looked about the biggest I could run on the wiring in my garage, hope it arrives before the weekend.

thanks for all the tips, as luck would have it my car just died so I have plenty of scrap metal to practice on.

[vanjam]

Some welding sites for reference are below but practice is the only thing really:

I've only done two jobs on mine, the first was "pooh", I hired a machine and didn;t have enough time to practice. just managed to tack on a small pice in front of rear whell arch. Bodywork guy coverd my tracks

The second was much better and I'm quite proud of it: I'd bought a 2nd hand 100A m/c and practiced in the garage first at length. It sound stupid but things get very hot, you have to be patient and apply small busrts and give time to cool otherwise the tin-can panels distort. Plan plan plan your welds.

When you practice use some crap rusty stuff and some good new stuff, experiment with the earth clip being really solid or just with light contact. Getitng to know the just how important good conductivity right through the system is will help.

Think very carefully about where you cut and how you will join. By far the easiest join for me was the "spotweld". It's not the same as the factory process but it involves lapping the two pieces to be joined and drilling small holes (the books say 5mm but I reckon 3mm) in the top sheet at regualar intervals along the seam and then applying the welder to the holes. If you do this, do NOT go in order-you need to dissipate heat. Do end, other end, middle,etc.

Clamping and cleaning-it's surgical levels of bare metal that are rquired in my view. Not just where yo're welding but throughout the circuit. Wire brush, grind and clamp everything as solidly as yo possibly can. My wleder's earth wire has a wimpish croc clip on the end, I file it's teeth and secure it to the metal work with clamp to ensure continuity.


It's a freaky fast expeirence-when the arc strikes you're suddenly melting metal at ridiculous temperatures. don't panic, you want a nice crackling bacon sound and LOOK you want to see a nice bead of excess moltem metal forming. Don't be afraid to stop and adust settings. But practice first cos panels are so thin they blow through easily

I'm about to do the wheel arch on mine so this willbe my third major attempt and I'm reasonably cofident-practice amkes perfect-good luck.

Have a fire extinguisher and beware all flammables nearby, the heat is unbelievabe


http://www.mig-welding.co.uk/forum/files/sip.pdf

http://www.mig-welding.co.uk/

http://eddiem.com/projects/mig/migmate.htm

http://www.twi.co.uk/j32k/protected/band_3/jk4.html

[skell]

practice last night went ok, exhaust making today not so well (pigeon shyte engineering incorporated...), but it's on and not blowing so that'll do me. Thanks for all the pointers.