Welder advice

[TFrench]

I put myself in novocaine's "not taught but can stick metal together" category. I've mainly used MIG as it's what we have at work. For a long time I just made it up as I went along, in the last few years I've made more effort to research and learn better technique and my welding has improved massively. Now if I'm going to try something I haven't done before I have a look on youtube for pointers before I start and make a mess. Recently I've invested in an AC/DC tig welder as well - now I can stick stainless and aluminium together badly

 

[sometimewoodworker]

Hi
I am thinking of dabbling in a little welding to add to my repertoire of useful skills and am therefore looking to buy a welder. I have absolutely zero experience of welding and would therefore like some help in choosing a suitable welder. I am looking for something that would be suitable for a beginner but would at the same time be good enough to stand me in good stead should I get hooked and end up doing a lot of welding. Pricewise I probably don't want a top of the range machine but nor do I want something that will pack up on me in a year the day after the warranty runs out. Thanks in advance, Andy

If you get a machine that does stick do get some 1.6mm and 2mm rods as it is easy to burn through steel when you start welding unless you are welding 3mm and up steel.

 

[Dave Moore]

Hi
I am thinking of dabbling in a little welding to add to my repertoire of useful skills and am therefore looking to buy a welder. I have absolutely zero experience of welding and would therefore like some help in choosing a suitable welder. I am looking for something that would be suitable for a beginner but would at the same time be good enough to stand me in good stead should I get hooked and end up doing a lot of welding. Pricewise I probably don't want a top of the range machine but nor do I want something that will pack up on me in a year the day after the warranty runs out. Thanks in advance, Andy

The beauty of using a mig comes when setting up as you can easily spot tack weld it. Using a headshield which is self darkening when the arc strikes leaves one hand free for setting up. Ensure everything is clean whichever process you use.

 

[heimlaga]

Whatever route you choose get a good quality welder of sufficient capacity. That makes learning a lot less frustrating and maker your new skill once aquired a lot more useful.

Myself I find stick welding with a DC welder to be the most useful method for my needs:
-I very rarely need anything thinner than 1,5mm welded and that is the thinnest I can stick weld with 1,6mm rods. A friend owns a professional grade MIG welder and weld the thinner stuff for me when needs arise once every second year.
-On the other hand I can stick weld thick materials. I can weld 30mm plate with 4mm rods if I want and I tend to have plenty of thick materials on various sorts of machinery. Rarely over 25mm though.
-I can also hard face a base material using the stick welder. For instance I built up my anvil with hardfacing rods because it was damaged beyond uselessness when I got it.
-I can nickel weld damaged cast iron parts using the stick welder.
-Stick welding is not affected detrimentally by windy conditions which is important as I live by the coast and have no fire proof workshop to weld inside so I must work outside. MIG or TIG welding hardly ever produces a decent result when working outside on a day when the weather is anything but calm.
-There are "gasless MIGs" with flux core wire which is not affected by wind but the cheaper ones have a very bad reputation for making weak welds and even the most expensive ones are one trick ponies with very limited versatility. Useless for thin materials and less versatile than stick welding for thick materials.
-Any AC stick welders are junk. I learned welding one an old Esab transformator and it was very difficult to master and even with the best of skills the result is mediocre at best. Therefore I sold the AC welder cheap very early on and got a proper 200 ampere DC rectrifyer stick welder. The "easy to use" ok46 and p45 sour welding rods often recommended for beginners and particularly for AC welders produce joints that are dangerously brittle and shatter like glass in freezing temperatures.

Then there are four main types of DC stick welders:
-Generators. The best of them all. A three phase motor powering a DC generator on a straight shaft. Produces an absolutely smooth DC current. Loud and heavy though. No new ones are manufactures to my knowledge and the moving parts tend to wear out unfortunately.
-Single phase or two phase rectifyers. A single AC current goes through a transformator and then through diodes making it a pulsing DC current. Decent weldes but not excellent.
-True three phase rectifyers. Two or three AC currents out of phase with one another each goes through it's own transformator and set of diodes after which the pulsing currents are joined into one almost smooth Dc current as the pulses were out of phase with one another. This is the type of welder that I have. I don't think they are made anymore. Even the small models weigh at least 150 kilos but they work very well.
-Inverters. The frequency of a single AC current is increased after which it goes through a transformator and a set of diodes. Produces a pulsing DC current with so short pulses that it is smooth in practice. Very good welders with great welding characteristics but very difficult to repair. Most new professional grade stick welders are of this type.

 

[OldWood]

I learnt to weld as an apprentice in year dot, so have forgotten it all. So what I say has no real weight, but my brother a year or so ago did a starter course somewhere in or near Motherwell. No doubtt the instructor was well intentioned and got the class started, but my brother reckoned he learnt more off YouTube videos than anything he got in the class, which I seem to remember he abandoned before the end.
Rob

 

[Beanwood]

I learnt to weld as an apprentice in year dot, so have forgotten it all. So what I say has no real weight, but my brother a year or so ago did a starter course somewhere in or near Motherwell. No doubtt the instructor was well intentioned and got the class started, but my brother reckoned he learnt more off YouTube videos than anything he got in the class, which I seem to remember he abandoned before the end.

I can only speak from the point of view of an amateur - I have welded for years with various degrees of success, and took a course just to satisfy my curiosity as much as anything else.
I think the point of an instructor is to help you when things LOOK OK, but aren't actually any good (Do you remember 'cold toes', where the weld looks realy neat, tidy, and hasn't actually penetrated properly !)
They can also help spotting set-up problems (Too much/too little gas, incorrect voltage or wire speed?)
And they can demonstrate with Mig that lovely 'sizzling bacon' sound, which tells you the weld is really going nicely.
Also the 'main' point of tutoring is to allow you to practice - which is really what welding is all about.

 

[Ttrees]

Never heard of the term 'cold toes' but I ain't a welder.
For fear it all might sound daunting for a newbie, making stuff from angle iron, I hope ye will grant me a licence to waffle a bit.

Thankfully cold toes are not really an issue with arc welding for what most need regarding workshop stuff like machine bases,
(most aren't using machines that weigh over a tonne)
And you can grind nice deep bevels in most cases and build up a good pool.
Were not building the Titanic, welding inch thick steel in stressful situations.
5mm thick angle iron is pretty stout.

Strange picture underneath of red hot metal to illustrate adequate penetration from this wee Lidl job.
Treat the puddle as custard and orient the work so gravity works in your favour.
Best practice if possible, no need to do vertical welds unless you're working on
something that cannot be disassembled, like tractors for instance.

And if in doubt grind it all back and start again, not an issue as most here are woodworkers, not price work welders who get a wasted rod or extra time taken out of their pay packet

And make a few picks from long masonry nails for removing any slag grit, as
if you can hear the grit, you can't weld on it.
This is important when joining up those good tacks that one might make,
before blasting it with a long bead to make it really skookum as frig, and not a wee measly tack like on many factory made things.
Tacks often required in different locations to counter the pull of the last good tack.

And wear goggles for the entire duration (yes under the shield/mask) and afterwards, until you can touch the metal with your hand, as it can act like water on oil and spit at you when you're cooking sausages.
Goggles kept on anyway for cleaning up with grinder, or finding slag with the pick that can ricochet at your eyes/teeth.
A bench grinder is handy to have for various picks, keeping one handled awl sharp, and for another nail or two that you hit with an tack hammer.

I fear that even I've made it sound complicated
I'm not the best at being straight to the point.
Good luck

Tom