Welding is easier than you think, pt. 1

I’ve been spending time with a local welder, Kari Merkl, working on an article for Woodcraft magazine, called “Welding for Woodworkers,” and I’m psyched to see how easy and affordable it is to get into the craft. Today’s small, user-friendly welders can join all sorts of steel parts, and then who knows what you might build: sleek furniture, junkyard sculpture, a tiny house or a tricked-out trailer.

I haven’t welded anything since a brief intro back in trade school 30 years ago, but I’ve always wanted to add welding to my arsenal. So I jumped at the chance to find a local expert and see what it takes to get started. Kari has been welding professionally for 16 years and teaching for 6, which makes her uniquely suited to break it down for beginners like me.

Watch Woodcraft mag for the full story, but here’s a taste of how easy and fun welding can be. I’ll do the basics first, then talk about adding wood parts in a later post. But keep following this blog because I plan to get my own rig and start building stuff with steel. If you’ve already beat me to it, let me know!

So welder first. You’ll be welding mild steel, specifically “cold-rolled,” which comes in lots of tubes and shapes with good dimensional accuracy and a nice, smooth finish. Other metals are harder to held and more of a next-level thing. But mild steel can do a ton of stuff, and be painted, power-coated or just protected with wax.

So for mild steel, MIG welding is the answer, at least for most of you. It’s the best combo of affordability, portability, affordability, and short learning curve. MIG stands for Metal Inert Gas, which just means the welding gun directs a stream of argon gas (with some CO2) into the welding zone to shield it from impurities in the air. Makes for much cleaner welds. But MIG is just a form of wire-fed arc welding, in which the work is grounded and then the welding wire touches the work, completing the circuit and instantly heating the wire and surrounding steel into a molten state, so it can bond together in a little puddle.

So there is a simpler wire-fed method, which forgoes the gas for flux instead. The flux is in the core of the welding wire, and creates a little shielding plume when heated. The weld isn’t quite as clean as MIG can do, but it’s still very effective.

Bottom line, you can get a gasless wire-feed welder for under $300 and for another $150 or so you can have a unit that does MIG, too! Here’s a great one that does both, from a very reputable company, Hobart.

hobart-handler-130

Voltage and the feed rate are controlled separately, as they should be, and the unit comes with the spool gun (with a few extra tips), some flux-core wire, and the grounding clamp–everything you need for flux-core-wire welding. If you add the tank of argon gas at some point, you can do MIG.

You will also need to prep your shop environment. If you can’t work in a separate room with nothing flammable for about 12 feet in every direction, you can shield the welding area with plastic welding curtains, as Kari is doing here:

a-wire-feed-welder-is-easier-to-afford-and-use-than-you-might-think

You’ll also notice the grounding clamp attached to a steel table, which in turn electrifies the workpieces being welded. You can also attach the clamp to the parts themselves, if you are welding on a concrete floor for example, or just put a steel plate atop your woodworking bench. The solid wood is spark proof too, but be sure there is no sawdust in sight or anything flammable, including open trash cans. And hang up those shielding curtains where needed!

You’ll also need some safety gear, like Kari has on, all thick cotton or leather, with a welding helmet.

Other than some practice and basic know-how, this is all that stands between you and welding! OK, you do need some way to cut metal, and your woodworking tools won’t work. Your wood-cutting bandsaw is way to fast for metal. So you’ll need a small metal cutoff saw (just over $100) or a horizontal bandsaw ($300-$400 new) designed for cutting metal.

Now to the basic technique. First of all, welding introduces tension and a lot of heat, so you need to distribute that heat and tension as you go or you will distort the assembly you are …assembling.

Basically, you get the parts squared up and clamped in place (there are cool welding clamps of this, or you can use any steel-jawed woodworking clamps) and then you first just make small tack welds at all the joints, moving systematically sound the assembly. Then you return to point A to make full welds. This balances the forces as you go, and lets the heat dissipate in each spot before you return.

magnet-clamps-hold-parts-in-place-for-welding
Mark used some cool magnet clamps to hold the parts in place squarely while she tacked all the joints together. This leg assembly got joined later to another one to complete the table base.
tack-the-parts-before-doing-full-welds
You work your way around the assembly tacking one area at a time.
after-tacking-all-the-joints-in-place-you-can-weld-them
Then you return to each area to do the full welds. This equalizes all the forces in the assembly as you go, and lets heat dissipate.

As for technique, it’s best to take a class and do lots of practice but here are the basics: you cut off the wire at about 1/4 in. away from the tip of the gun, tilt the gun about 60 degrees to the surface and pull it along ahead of the weld, trying to keep the tip of the gun about 1/8 in. off the surface. The tilted gun lets you see the weld area as you work.

 

You also need to swirl the tip of the gun as you go to create a wide, strong bead. Welding is a dance of sorts, between voltage, wire feed rate, and your own motion, as you move the molten puddle down the weld, and that dance takes practice. But you can do it!

practice-makes-perfect
This is the angle and height you should keep the spool gun at, and this is about how wide a good weld should be. You can see the swirling action in the weld.
a-brass-brush-cleans-off-the-slag
A wire brush cleans say the slag off the weld, and 3M pads can do the rest of the polishing. A couple coats of paste wax completes the job. Then the frame is done!

Kari says the hardest part for beginners is learning to see the entire weld as you work, training your brain to see a bigger circle through the lens in the white light, and also just getting comfortable with the sparks, sound, and light. But she gets beginners to nirvana all the time, so you can do it too.

 

After spending a couple days shooting photos at her studio, I’m positive I can weld. Still I’m going to one of her classes this weekend to try it for real.

Stay tuned for part two, where I show some of the finishing touches to a welded frame, and how to add wood to it to make a nice coffee table.

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