The “one tool that does everything” is kind of like the Holy Grail for anyone that likes to make stuff. This is probably why multi-process welders are so intriguing. Can they really do it all? Are they worth it?
Multi-process welders can be totally worth it for home hobbyists or those that do small amounts of welding. For industrial applications or when welding is a critical aspect of what you do, you’ll want to stay away from them.
The issue of what tool is right for the job always comes down to a single question:
What are you going to use it for?
In this post, I’ll share some information that can help you to make a good decision for what you do, and I’ll help you understand what you can expect out of one of these machines. I’ll also share some buyer’s tips to help you pick one out.
What Multi Process Welders are Good For
Multi-process welders are a great option for your garage if you want to have the ability to do a few different types of welding operations at a reasonable price point. Although they’re generally more expensive than a single-process welder, they’re also much cheaper than buying multiple welders that each do one function.
Most multi-process welders (MPs) can do two or more of the following processes:
- Flux-core wire
- Plasma cutting
I should just mention here, that just because a welder can do two of these functions, that doesn’t necessarily mean that it’s classed as “multi-function”. For example, my Lincoln 225 TIG welder can also do stick welding, but it’s very much a TIG welder. The stick welding is more of an afterthought since it’s such a basic function.
Also, MIG welders that can also do flux core are kind of the standard, too. If it can do MIG welding, it has everything it needs to run gasless as well. It kind of goes without saying, so it’s not really considered a multi-process welder either.
Generally, MP welders are 110v/220v smaller machines that are for lighter-duty applications, like welding up to 3/8″ thick steel plate or so. They’ll do some varied combinations of processes, like TIG and MIG. For the home hobbyist, that’s generally more than enough. For industrial shops, probably not.
If you’re not completely familiar with each of these types of welding, I’d highly recommend that you do your homework. I wrote an article here about different types of welding, but it’s worth doing a deep dive to know what questions to ask.
So the benefits seem pretty obvious for multi-process welders. If you want to do a few of these operations, an MP welder seems like a good choice.
Where Multi-Process Welders Don’t Make Sense
MP welders generally don’t make sense if you’re not regularly going to use more than one of the functions. For example, it’s not really worth spending more for TIG welding if you’re really only going to be using flux-core arc welding. You’re better off spending your money on a better quality flux core or MIG welder.
Another rule of thumb is that a jack of all trades is a master of none. For all multi-process welders, it’ll do some functions better than others. For example, it might do great as a MIG welder but lacks finesse/functionality as a TIG. This may or may not be important to you.
It also doesn’t make sense if you really rely on the welding machine and need, let’s say, two of the functions. For example, if you’re running a small welding business, and you only have the one welder, and your inverter dies, everything grinds to a halt.
That said, it’s never good to be critically dependent on one single machine if your livelihood depends on it.
You’re best off just getting two machines that do what they’re intended for and have them work reliably. They’ll perform better, too. It’s next to impossible to simply read reviews and understand not only what the machine does well, but where it’s weak. There are a large quantity of first-timers writing rave reviews on multi-process welders than wouldn’t know a good TIG weld if it bit them in the… somewhere.
What Nobody Tells You About Multi-Process Welders
There’s one main thing that generally goes unnoticed when people are looking into a multi-process welder for the first time.
The gases for each type of welding are different.
For plasma cutting, you’ll probably use just regular shop air. For TIG welding, you’ll use an inert gas like argon or an argon/helium mix. For MIG welding, you’ll probably use CO2. For stick welding, you’ll just breathe the fumes instead.
The point is, even if your machine is capable of doing 4 different processes, getting all the gases ready and available can be an expensive hassle.
The only really convenient way around it is to set up for TIG welding (pure argon or 75% argon/25% helium mix) and then use flux-core arc welding and/or stick welding.
That way, you don’t need to buy or rent expensive bottles and you don’t have to worry about changeovers aside from the electrode holder/gun.
Even still, you’re limiting yourself and usually not really getting as much as the sales page lets you believe. You’re probably not going to want to properly set up for both TIG and MIG with a multi-process welder. If that’s what you need, you’re best off not having to constantly swap out bottles and just get one of each machine.
Hopefully, so far you’ve been able to narrow down whether or not a multi-process welder is right for you. Now here are some buying tips.
How to Pick the Right Multi-Process Welder
Some of these are general-purpose tips for buying any kind of welder, and some of them are specific to MP’s.
Off-Brand = Less Amps
Now I’m not saying that the only welders that actually put out the rated amps are Lincoln, Miller, Hobart, and the small handful of other brand names.
However, if you’re eyeing up a super cheap multi-process on Amazon, just be aware that the output amp rating is much different from what is actually output. Sometimes, you’ll only get half of what’s advertised once you check it with a multimeter.
That’s one of the reasons that many choose to spend more on a recognizable name. If it says 200 amps for TIG welding 5/16″ steel, you’ll actually be able to weld 5/16″ steel.
For the off-brand super cheap ones, you’ll probably either blow up the machine or just never get proper penetration if you try to run it at max amps.
Just Because it Can TIG Doesn’t Mean You Can Weld Aluminum
For a lot of the MP machines out there, TIG is only offered on DC, not AC. This means that it’s not well suited for aluminum.
Alternating Current has a cleaning effect on aluminum, and it’s much needed. Aluminum oxides will mess up your weld pool and ultimately make your welds break if you run DC.
Dual Voltage has Downsides
A lot of the multi-process welders that attract hobbyists and small shops are dual voltage. Obviously, it’s nice to be able to plug a welder into any outlet and go to town.
However, it’s worth knowing that you can’t weld as thick of metal on 110V as you can on 240V. So, while it’s convenient, you should at least be aware that you might not be able to weld what’s advertised unless you’re on 240V.
Pay Attention to Duty Cycle!!!
This is important, and lots of hobbyists don’t know what this means.
Duty cycle is how long the machine can run continuously based on a 10-minute period.
So if a machine has a duty cycle of 30% at 100 amps, you can run it for 3 minutes, then let it cool down for 7 minutes. If you’re running at a lower amperage than the rating, you can run continuously for longer.
What happens when you exceed the duty cycle?
Ideally, the machine will just switch off and stay off until it cools down. It’ll have a thermocouple in there somewhere that tells it to take a break.
But if you keep maxing it out like that, you might end up with an aroma of burning plastic, and possibly even a burnt-out machine. Just be aware of how long you’re welding continuously, let the machine take breaks, and you’ll be fine.
If you want a better understanding of how duty cycle works, you can get the complete explanation here:
What “Duty Cycle” Means for Welding Machines
Multi-Process Welder Recommendations
This could be a never-ending list of everything that’s out there, but I’m going to keep this really simple. Feel free to do your own research to pick out the one that’s just right for you, but here are some popular (for good reason) machines, along with what they can/can’t do.
Cheap, does a few things OK but nothing wonderful:
You can buy these multi-process welders from Lotos on Amazon that are OK for hobbyists, but it’s hard to argue with the price being so low. No MIG/flux core, but as a plasma cutter, very basic DC TIG (no aluminum) and arc welder, you can do a lot for cheap.
The “very basic TIG” means that you’ll probably want to spend a bit more at some point on a few more accessories, like a foot pedal. Even still, you won’t be able to compete with the pros that can drop dimes on every pass.
The one cost to factor in is for a bottle of argon. It’s worth calling your local weld supply shop first just to know what to expect price-wise before committing.
If you just want something to handle miscellaneous jobs that come up in your garage, then this is probably exactly what you’re looking for.
Less multi-process, but highly capable:
I feel that one thing that’s often overlooked is that you can MIG aluminum if you have a spool gun. It’s worth doing a bit of research on, but this is an excellent and fast way of getting the job done.
If you’re wanting to weld steel and aluminum, and don’t really care about the rest, then I’d highly recommend taking a close look at this MIG package from Lincoln. It’s great bang for your buck in the name-brand world. Just make sure you get the spool gun for aluminum welding.
Again, spool gun MIG is a much faster way to weld aluminum than TIG. Just keep in mind that you’ll still need to use argon instead of CO2 when welding aluminum.
Aside from those two basic options, I don’t really feel that there are too many worthwhile choices. You can buy name-brand multi-process machines, but they’re expensive and often more prone to breaking when they’re in the sub-$6k range. Buying anything cheaper than the Lotos welder off the internet is going to be really sketchy, and it’s unlikely to perform very well.
So are multi-process welders worth it? Kind of. Maybe. It depends. What do you want it for?