The ***ALL NEW*** AUSubaru.com.au Forums

Hmmm... So I've only just noticed that there's not a workshop sub forum for body work!

Got a couple of questions - I'm now getting into having a crack at some body work and wanted to know what sort of drill bit should be used to drill out spot welds.

Also what sort of welder would be good for the light requirements of sheet metal work as I might get one for keeps?

I'm aware of issues associated issues with heat and panel warpage.

Any pics or info of tools etc would be great

Cheers

Bennie

Spot weld drills:
http://www.ebay.com.au/itm/3Pce-6mm-8mm ... 58c8a1100e

Use the solid HSS/coated kind not the mini-hole saw kind, slow speed with a good drill and cut through the top layer of steel only. May need some further coaxing with a hammer and chisel or something slipped in between the layers to pop them apart.

Welders: Don't even think about stick welders! MIG with shielding gas is the only way if you aren't any good with an oxy set. Even gasless MIG is no good for panel steel. You'll want one with interchangeable wire feed rollers so you can use a thinner wire (.9mm way too big) I splashed out and got a multi process inverter (transmig 175i) but a cheaper transformer type would do the job, as long as you can dial down the power settings properly (the ones they sell at Funnings don't have enough control over the power settings) Cigweld do a range of machines that would be suitable, if you don't want to buy one new you could probably get one second hand. As for gas there are those tiny disposable bottles at funnings, but I've never used them. I just rent a bottle from BOC and be done with it but I know that's not for everyone. Don't weld in one continuous bead, just lots of small spot welds. Do a few at a time then let the area cool a little. And practice on scrap first!

So what car is this lined up for anyway? some repairs to Ruby scoo or does Redback need some TLC?

Bottle rental is killer unless you have a hook up from someone that has a business of fabrication. Supagas, speed gas, machinery house etc do the buy / swap and go cylinders for around the $300 + 60 for a refill compared to boc $20 odd month rental but cheaper refills, airliquid has joined the buy cylinder game with an inbuilt reg on top of the bottle for $250 odd. Disposable bottles are good but heaps smaller, require a different adapter or different reg to work, and super expensive $50/60. Compare volumes in the cylinders v price, you don't need a 5 foot cylinder for occasional home use. I bet you could onsell the gas cylinder if you got a "buy/ swap & go" in minutes if you needed to cash out.
Welding like everything in life, fits into the once a year / weekend warrior / handyman / tradesman markets. Think eBay / gmc ryobi / makita / hilti or festool for power tools. There are exceptions to this too
Welders, I have a unimig 180, about $500, it's good but not great. Couldn't afford a Lincoln or fronus 180 $1000+ haven't used it with gas yet but gas less works fine for me just needs heaps more clean up of splatter around welds, think 1 foot around weld for repainting rather than centimeters. Also have a migomag (boc) 285 and remote feeder but no 3 phase power to run it.
Whatever you buy make sure it has an infinite adjustable power and wire feed adjustments, rather than fixed setting 1,2,3 etc. it's so frustrating not being able to wind back power just that "little" bit more but not a whole settling.
Welding helmets, any of the major brand auto darken helmets work pretty good once dialed in and cheapish without having to buy a miller elite digital. Good consistent lighting (overhead & movable floodlights) vs position of sun etc make more of a difference with your welding than 20 sensors vs 2 . I have a cig weld one because spare parts for it are available at nearly every hardware store around. Eg magnification lenses, gold filters, lense protectors etc.
If your having trouble seeing the weld "pool" with consistent practice conditions, lighting and position etc give these $10 gold lense or 2x magnification lenses a try by taping them to the inside of the helmet. It can be "eye opening" the difference they can make.
Spot weld drill bits as above, I haven't had much success with the holesaw type. I've had more success with a carbide burr in a die grinder for spot welds but you can make too big a hole easily.
Grinding down welds with the edge of a 1mm cutting wheel on a grinder reduces the heat affected zone/ warpage in the panel compared to a grinding or flap wheel. Just be careful you don't force it to flex the cutting wheel and then it shatters and bits fly everywhere in its path causing damage eg arms, face, car panels etc.
if your starting from scratch, consider a starter pack. Think of it like an apprentices first tool kit. Eg Lincoln ready-pak. It comes with helmet, gloves, jacket / apron pliers etc and usually an instruction dvd. They should be available from all the big names at a welding shop. Expect a big discount if you buy a welder from the same place..
Just remember practice makes perfect and fit up as good as you can make it will save 5x the time it takes in grinding and bridging gaps with welding.
Only weld clean metal unless your fixing a farm gate, the weld will be less porous = less likely to suck in moisture and then start rusting from inside out.
Brumby brand scouring wheel / pads are a god send for removing paint around where your welding compared to flap wheels, grinding disks and paint stripper and so much quicker too. Available at big green shed with 3 different grades but blue available at most hardware stores usually cheaper than bunnings too.
Upol copper weld through primer is the bomb but normal zinc weld through primer is still good.
Kill rust rust eater / converter and hd etch primer in a spray can are great for stopping flash rust after welding prior to full painting but you really need to seal / full paint within a week or two. Check if the top coat paint you use doesn't react to it too. Just in case
Sikaflex panel bond to seal any gaps. Used to hold Commodores together so it works.
Buy bondo / hi fill from a trade supplier rather than supacheap as the advice is far better and usually the price too. So much easier to sand down too.
If you get carried away and decide to respray the whole car, consider valspar lic40/43 or protec single stage "industrial" paints. They can be mixed to a colour you want, are cheap, require far less sanding for surface prep, don't need a clear coat and are self leveling which can mask a rougher surface prep / beginners paint skills better. Less need to a wet sand it. Approx $200 or less for 4 liters inc hardener and thinners. Often used on horse floats and trucks and semi trailers.
Cliff notes:
Practice makes perfect, but good fit up makes it easier.
Take your time / let panel cool to reduce warpage.
Any big name welders will be capable, panel welding is going to be sub 50 amps so no need for a fabricators spec welder. Just make sure it's adjustability is good not fixed.
Get a auto darken helmet that has good local parts support, lenses etc and easier to take back if faulty.
Gas bottles, search around for local dealers and prices v buy/ rent.
Expect the bottle to always empty Saturday just after every shop shuts. Murphy's law
Expect everything to take 3 x longer than you estimate

YouTube was made for instructional videos. weldingtipsandtricks and many other great resources

This is what I am going to use rather than signing up for BOC: http://www.ebay.com.au/itm/Argon-5-2-Ga ... 3cf38b1c16

Certainly better value than the disposable bottles, although whether it is better than signing up with BOC will depend on how much you have to weld I suppose...

Once my tax return arrives I will also get this: http://www.ebay.com.au/itm/New-Unimig-R ... 27feab5a75

Then it will be practice, practice and more practice!

sublime wrote:This is what I am going to use rather than signing up for BOC: http://www.ebay.com.au/itm/Argon-5-2-Ga ... 3cf38b1c16

Certainly better value than the disposable bottles, although whether it is better than signing up with BOC will depend on how much you have to weld I suppose...

Just for reference; I have an E sized bottle of Argoshield light (80% Argon, 20% CO2 designed for light gauge and sheet metal welding) which is 4 cubic metres/4000 litres From BOC that's $50 every 3 months so $200 a year. When it goes empty I take it back and swap/refill for <$60. I've had it well over a year and so far it's not even half empty. And that's after doing almost all the welding on my wagon resto, half a lift kit I made, plenty of other little jobs and I helped Phizinza with some custom exhaust work on his ex-race wagon.

I don't mind paying the rental, because it's always there when I need it and there's enough in the bottle that I don't have to worry about running out halfway through a job. That peace of mind is worth the money to me And although it's the "light" argoshield you can still use it on up to 6mm material which is all my machine can do anyway. Perfect for custom bull bars!

Some awesome advice there guys! Definitely have to decide on what I want to go with now. Those drill bits are the first thing I reckon then I'll go from there.

Sb, you should know I've always got a project brewing in the background

Cheers

Bennie

So impressed with these responses and the level of expertise out there

This forums future is secure if we band together and keep it going.