Help me with my first ever mig welds, why do they look like Swiss cheese and will I ever improve (cry for help after being demolished on Reddit)

[moesizlak]

Welding is what I term one of the "rough" arts. I work next to a good welder. I can weld OK using the gun/gas he's set up. But it's far from the trials of woodworking. Cut it a bit short? Just fill it with weld. Cut one a foot to short? Weld a bit on.etc. Once you can add to stuff mistakes are easy to put right. The material is also cheap and homogenous and in very long lengths (5m). The most strange is his bandsaw blades last longer than mine! (both m42).
Just keep trying and turn it up....

Yessir!

 

[pe2dave]

And I thought woodwork was hard!
[if needed, I'll get a welder in!]

 

[Tris]

As an aside, does anyone know of places doing basic courses?
Looking around here even the agricultural colleges have stopped doing them and the old techs have long gone

 

[moesizlak]

As an aside, does anyone know of places doing basic courses?
Looking around here even the agricultural colleges have stopped doing them and the old techs have long gone

^^^

 

[XTiffy]

Ed China (of the car restoration programme) has made a Youtube video on the subject, which is very well done and explained, well worth a look.

I learnt arc welding and Oxy- Acetylene back in 1977 when Mig and Tig welders were very expensive. I still have my old oil filled Oxford welder (hernia inducing to move). I had some heavy duty strucural welding done a few years ago to my barn by a professional and I was amazed at the small size and portability of his welding machine.

 

[pe2dave]

Here it is
He has others on welding too.

 

[Jake]

So make sure that surface is CLEAN (and that includes things like oil from your hands even can cause that porosity- and even from earlier welds- clean before each new weld!!!) and experiment with your feed rate, amps, gas flow and the 'speed' of your torch travel... the best one is right at the top)

Oh yes, I missed that one - much better penetration.

 

[Spectric]

Welding courses used to be a common thing at many colleges, I did C&G courses at both the Colchester Institute and Braintree college. It really depends upon how much spare time you have and how far you wish to pursue welding because you could enroll on a C&G welding course. There is a lot more to welding than many seem to think, it is a case of several things all coming together at the same time, ie welding equipment setup, joint preparation and then you the welder and more important than a good weld is the ability to reconise a bad one !

I still have my old oil filled Oxford welder

Will last forever and what many welders of today probably learned by using one. The modern ones using invertor technology do look very lightweight and I doubt they would be capable of having a long duty cycle where you could weld continously for hours before they shut down, those Oxfords would just keep going.

 

[Spectric]

With MIG I should have mentioned that if using a gas MIG then the electrode is positive but if for whatever reason you are using one of those gasless MIGs then it should be negative.

 

[Phil Pascoe]

I looked at evening classes for MMA, it's a long while since I welded. Sixteen hours over eight weeks, inc. MIG and TIG which I'm not really bothered about worked out at £26+ per hour. I know a very good welder and I'm going to slip him £50 here and there to guide me.

 

[--Tom--]

Still learning to weld myself so pinch of salt with the below:

Mig needs clean metal so go over the surface with a flap disk first
This keeps your weld pool clean and helps avoid porosity.


Set your amps and gas flow rate for the task at hand - when learning this is hard and experience helps a lot with getting the sizzling bacon.

From the looks you’re also long arcing which is leading to the spatter, feeding the pool to maintain arc length is another practice practice practice thing to learn

 

[AutoDoc Williams]

And there is nothing finer and more satisfying than stepping back and admiring the workmanship of your colleagues boots welded to the bench by their steel toe caps.

or their locker welded shut!

 

[AutoDoc Williams]

Do whatever you did on that upper right weld. Just keep trying and messing with speeds and voltages. Also understand that the thickness of whatever you're welding will require that you fiddle with those speeds and Volts again. You'll get it, just keep practicing.

 

[Spectric]

Learn TIG and you can weld anything in any position and get welds that look like they have been drawn on with perfect penetration. It is also easy to weld thin metal to much thicker metal because of the precise control and localised heat source. The only down side is the need for pure Argon for the shielding gas which has never been cheap.

 

[Dabop]

Welding courses used to be a common thing at many colleges, I did C&G courses at both the Colchester Institute and Braintree college. It really depends upon how much spare time you have and how far you wish to pursue welding because you could enroll on a C&G welding course. There is a lot more to welding than many seem to think, it is a case of several things all coming together at the same time, ie welding equipment setup, joint preparation and then you the welder and more important than a good weld is the ability to reconise a bad one !


Will last forever and what many welders of today probably learned by using one. The modern ones using invertor technology do look very lightweight and I doubt they would be capable of having a long duty cycle where you could weld continously for hours before they shut down, those Oxfords would just keep going.

I'm in Aussieland, and here we have 'TAFE' colleges that do 'night' or weekend short courses that are run several times a month in many cases, very cheap indeed plus plenty of others doing 'home handyman welding courses

Even the local Bunnings (the largest of our aussie hardware chains) holds regular 'DIY' workshops at their stores, which include lots of different subjects (including basic welding techniques) on a regular basis, the welding one pops up every month or two...

I still have my old Transarc stick welder (although I haven't actually used it in a couple of years lol)- literally takes two people to lift it in and out of the ute, and is a huge metal box on wheels that weighs a tonne!!!
(not mine, but its identical- well sorta- that one looks like its a lot newer than mine, which has the old solid rubber tyres on it- I bought mine secondhand (and it was OLD then) back in 1983???)

These days, these are the 'goto' tools for 99% of my lighter metal stuff- plasma cutter on the left, and gasless mig on the right...

(gasless mig in particular is great- actually quite cheap to run in comparison to the gas migs (which I have as well) but here you can only rent the argon bottles- and thats well over a hundred bucks a year- too $$$ for 'home handyman' use...)- and they are free to run in electricity even for me (offgrid solar here lol)

And yes- grab a 'auto darkening' helmet- makes life a LOT easier- and you can pick up a cheap one for under $50...

 

[TRITON]

Another funny welding prank is to replace the rod on an arc welder with a sparkler