Welding question... newb at it...

[Jon K]

Just got an Arc welder. I was wondering a few things.

An arc welder, so I understand, is essentially a huge ground loop/short that heats the wire and thus it fuses to the base. Because its like a big electrical short, does that mean I shouldn't or can't weld on the car? For instance... the exhaust hangers? Could I weld an Exhaust hanger to the car or what i need to disconnect everything electrical?

My other big BIG BIG question is... could I weld a bracket to my block? Obviously I don't want to penetrate the block, but it's an arc welder and it beads... I have an M50B25 and want to weld 2 steel "sleeves" if you will so I can bolt a bracket to them. I think the block is Iron, will this work? Will i blow the car up? What would I do to go about this?

[bahnstormer]

u shouldn't weld anywhere near your gas tank.... so where u want to mount these
hangers?

[Jon K]

u shouldn't weld anywhere near your gas tank.... so where u want to mount these
hangers?

The hangers was a theoretical question, I am more interested in getting a couple threaded sleeves bolted to my block so i can mount a bracket of sorts

[bahnstormer]

is there no other way around it? i'd hate to think of messing with the block for fear of structurally weakening it. =\

but ii've never welded before, so lets see what others say

[George Davis]

Jon,

short answer is no, you cannot weld to the block. The long answer is that cast iron can be welded using special rods, maybe special welders, lots of skill and experience, and probably some way to preheat the area to be welded. But for us amateus, just no.

There is some risk using any electrical welder on computer controlled cars. I don't know how big the risk is, but I've seen it mentioned in other places. There may be ways of reducing the risk, maybe by disconnecting the battery terminals, but I'm not really sure.

Last, I'm not sure if you want to weld brackets to the car, but an arc welder isn't the best way to do that. It would be very easy to simply blow big holes in the sheet metal and not get anywhere.

And one more thought: pay attention to what's on the other side of where you're welding. It's easy to forget about insulation and carpets, but it only takes a couple of seconds of welding to set them on fire...

There are tons of things to know about welding before you strike an arc on your car, and in particular you need to know the limitations. Some types of welders can weld upside down, some can't; some will weld sheet metal, some won't. Find a good book about welding and read everything that applies to arc welding, then practice a lot on scrap metal of varying thicknesses to see what happens.

Good luck!

[DueyT]

Jon, arc welders (I'm assuming yours is a standard AC "buzz-box") tend to be more useful for medium to heavier fabrication work, like about 1/8" steel or heavier. For lighter stuff, you'll want to go with MIG (metal-inert-gas, also call GMAW or gas-metal arc welding) or TIG (tungsten-inert-gas, also called GTAW or gas-tungsten arc welding). Both are able to control weld heat and penetration much better than arc....down to 22-26 guage sheet metal in many cases. MIG uses a wire-feed material shielded by an argon-CO2 gas to keep impurities out of the weld. Once you get the hang of it, MIG'ing is actually fairly easy...but still needs practice to make nice welds...wire-feed speed and heat setting takes a bit of playing around and experience with your own welding set to get right. TIG uses a tungsten electrode and you feed filler rod in seperately. TIG can control heat quite well, like oxy-acetylene but capable of doing so in a much smaller area.

George is right...welding cast iron is not recommended for the novice...many experienced welders also stay away from welding cast iron for a number of reasons: very finicky, especially with cracking...it expands a fair bit under heat then cooling can induce stresses in the area immediately around the weld. Some folks heat the entire cast-iron area to be welded with an oxy-acet torch, then arc weld or oxy-acet weld it. I think most experienced welders will recommend brazing cast-iron instead...brazing doesnt actually fuse the base and filler metal, but rather like soldering "fills-in" hot brazing metal between the two metal pieces you would like to join.

Jon, I would recommend Richard Finch's book, "WELDER'S HANDBOOK: A Complete Guide to MIG, TIG, Arc and Oxyacetylene Welding", ISBN 1-55788-264-9, to get you started. I bougth this book years ago and continue to use its ragged pages today.

I have a small Lincoln 110v MIG unit and love the thing...I do a fair bit with it, all around the house and the shop. I made my first project a practical one, and built a cart for the welder itself. After that I've made sandblasting cabinets, welding tables, bird feeders, repaired car's sheet metal, repaired exhaust systems, you name it...you'd be amazed how much stuff you can weld. In fact, my nephew and I are in the process of welding up a hockey net for him and his friends for some street hockey...it's a lot more fun than going out and just buying something.

p.s. about the hangars (or anything else on an ECM-controlled car) DEFINITELY deisconnect the battery, and to be really safe, I would also consider disconnecting the DME.

Cheers,
Duey

p.p.s. my first project...

[winfred]

i second that, i also have finch's book and it's a good resorce, with the right rod and power setting it wouldn't be too much trouble to do do some light sheet metal work but that's up to the skill level of the welder to control the heating of the part, which is hard to do with a buzz box. a alternitive to welding to the block would be possibly bolting up to the block if theres a couple conveiniant threaded bosses, theres several bosses all over the block for other cars accessorys/brackets, bolt a piece of steel up and weld to that. i have a ac/dc buzz box a decent sized 110v mig and my latest toy a plasma cutter, now i want a tig (or a high frequency control unit to use my buzz box as a tig, if i could find one)

Jon, arc welders (I'm assuming yours is a standard AC "buzz-box") tend to be more useful for medium to heavier fabrication work, like about 1/8" steel or heavier. For lighter stuff, you'll want to go with MIG (metal-inert-gas, also call GMAW or gas-metal arc welding) or TIG (tungsten-inert-gas, also called GTAW or gas-tungsten arc welding). Both are able to control weld heat and penetration much better than arc....down to 22-26 guage sheet metal in many cases. MIG uses a wire-feed material shielded by an argon-CO2 gas to keep impurities out of the weld. Once you get the hang of it, MIG'ing is actually fairly easy...but still needs practice to make nice welds...wire-feed speed and heat setting takes a bit of playing around and experience with your own welding set to get right. TIG uses a tungsten electrode and you feed filler rod in seperately. TIG can control heat quite well, like oxy-acetylene but capable of doing so in a much smaller area.

George is right...welding cast iron is not recommended for the novice...many experienced welders also stay away from welding cast iron for a number of reasons: very finicky, especially with cracking...it expands a fair bit under heat then cooling can induce stresses in the area immediately around the weld. Some folks heat the entire cast-iron area to be welded with an oxy-acet torch, then arc weld or oxy-acet weld it. I think most experienced welders will recommend brazing cast-iron instead...brazing doesnt actually fuse the base and filler metal, but rather like soldering "fills-in" hot brazing metal between the two metal pieces you would like to join.

Jon, I would recommend Richard Finch's book, "WELDER'S HANDBOOK: A Complete Guide to MIG, TIG, Arc and Oxyacetylene Welding", ISBN 1-55788-264-9, to get you started. I bougth this book years ago and continue to use its ragged pages today.

I have a small Lincoln 110v MIG unit and love the thing...I do a fair bit with it, all around the house and the shop. I made my first project a practical one, and built a cart for the welder itself. After that I've made sandblasting cabinets, welding tables, bird feeders, repaired car's sheet metal, repaired exhaust systems, you name it...you'd be amazed how much stuff you can weld. In fact, my nephew and I are in the process of welding up a hockey net for him and his friends for some street hockey...it's a lot more fun than going out and just buying something.

p.s. about the hangars (or anything else on an ECM-controlled car) DEFINITELY deisconnect the battery, and to be really safe, I would also consider disconnecting the DME.

Cheers,
Duey

[632 Regal]

Id have to say for all around welding a mig is going to be a better choice for a beginner and even someone with more experience. My mig can weld sheetmetal (within reason) all the way to thick steel with a couple passes, roll cages and even stainless steel and aluminum. All you need is the wire, settings in the hood. Lots of welding boards out there for help too. Heres one I havent been to in a long time so if it dont work shorten the /... and get to the main page.

http://www.hobartwelders.com/mboard/....php?forumid=4

[Springfield1952]

Welder brand question . . . I've been thinking of getting a MIG welder for all the reasons that Duey mentions and my son is taking a welding class at the local JC next semester. For brands there's Lincoln, Hobart & Miller that I've heard of. Any strong pros or cons to any of those 3? Is there another brand that's a must buy? TIA.

Curt.

[winfred]

any of the big 3 brands should do fine

Welder brand question . . . I've been thinking of getting a MIG welder for all the reasons that Duey mentions and my son is taking a welding class at the local JC next semester. For brands there's Lincoln, Hobart & Miller that I've heard of. Any strong pros or cons to any of those 3? Is there another brand that's a must buy? TIA.

Curt.