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DamienS
12th Feb 2008, 01:30 PM
G'day all,

Well im brand new to your forums as well as welding, im a drafty whos decided that is about time i learnt how to weld seeing as though i specify everyday whaich welds and where to put em.

So i got a 160Amp Easiweld machine from a mate and have been giving it a go on some light steel SHS ( 25 x 2mm ).
After reading the many posts regarding electrode size i now understand about the elctrodes being basically the same size as the material your welding, and Amps ratioed to electrode size, however im really struggling when it comes down to the actual welding of the 2 peices together. Ive got some 2mm electrodes and turned the amps right down but no matter what i do i seem to be blowing big holes through the joint. ( trying just a straight tee joint ).

I was told by anothe bloke that i would be better to get rid of it and just grab myself one of the gasless MIGs that would handle this much better but at this stage would prefer to learn on what ive ogt first before outlaying a load of cash...

Any advice? Also what speed should i be putting the run down at?

Thanks,

Damien

wheelinround
12th Feb 2008, 02:12 PM
Hi Damien and welcome aboard the good ship U-Beaut

Its hard to get started make sure you relax as much as you can use scrap and hang the cost of rods till you settle down.

How fast you move your hand "slower and the bigger you'll blow-er" "fast and it look like a rats Ar%$ "

what also counts the gap between the rod and work approx 1mm

Can I suggest you grab something a bit thicker and work down using the same rod higher amps.

Ray

Vernonv
12th Feb 2008, 04:04 PM
I agree with Ray ... get some thicker stock and electrodes to practise with and up the amps a bit. It will be a lot more forgiving and allow you to "play" a bit more without blowing holes and getting frustrated.

Then just practise, practise, practise and when your finished practising, practise some more.:roll:

I started with stick welding and eventually got a MIG, but I only use the MIG on thin stock and still prefer the stick for anything over about 2.5mm or 3.0mm.

Grahame Collins
12th Feb 2008, 06:39 PM
Well im brand new to your forums as well as welding, im a drafty whos decided that is about time i learnt how to weld

I was told by anothe bloke that i would be better to get rid of it and just grab myself one of the gasless MIGs that would handle this much better but at this stage would prefer to learn on what ive ogt first before outlaying a load of cash

Good on yer Damien and Welcome to the mob.

Itis usually the arm chair experts have have had little or no experience in stick welding light metals, that offer such sage advice as you have been getting.

It takes :

the right equipment - You have it already
knowledge and understanding of the correct techniques ( you will get them here)
and the will to succeed and not give in easily-

We have a good strike rate of successfully assisting blokes who formerly thought welding thin stuff was nigh impossible.

Give us an idea with the specifics of what you want to achieve and you will get a ton of help.Feedback is the key to apply specific procedures to specific applications.You want to do it and want to have a go .You are half way there already.

I have posted some diagrams and info on welding tin wall tube as you describe and will search for the links.

Cheers
Grahame

Grahame Collins
12th Feb 2008, 07:16 PM
Hi Damien
Back again

This lot should keep you busy reading for a day or two at leasy,
I have had brain fade on the diagrams I am buggered if I know where there are.

Can any one remember the diagrams done in MS Paint on welding thin box?. They gave the angles for welding thin wall box section.

http://www.woodworkforums.ubeaut.com.au/showthread.php?t=65396

http://www.woodworkforums.ubeaut.com.au/showthread.php?t=61524

http://www.woodworkforums.ubeaut.com.au/showthread.php?t=59869

http://www.woodworkforums.ubeaut.com.au/showthread.php?t=60190

Grahame

wheelinround
13th Feb 2008, 08:26 AM
Good on yer Damien and Welcome to the mob.

Itis usually the arm chair experts have have had little or no experience in stick welding light metals, that offer such sage advice as you have been getting.

It takes :
the right equipment - You have it already
knowledge and understanding of the correct techniques ( you will get them here)
and the will to succeed and not give in easily-We have a good strike rate of successfully assisting blokes who formerly thought welding thin stuff was nigh impossible.

Give us an idea with the specifics of what you want to achieve and you will get a ton of help.Feedback is the key to apply specific procedures to specific applications.You want to do it and want to have a go .You are half way there already.

I have posted some diagrams and info on welding tin wall tube as you describe and will search for the links.

Cheers
Grahame

Thanks Grahame for the insult to the TAFE teacher who spent 3 years teaching welding the 3 boilermaker Welders who were masters in their craft. that I worked with :2tsup:. To those fellows I say thank you for teaching me what I have used for nearly 35 years.

Vernonv
13th Feb 2008, 08:53 AM
:((Hmm, was Grahame referring to us ... or this "bloke":?.


I was told by anothe bloke that i would be better to get rid of it and just grab myself one of the gasless MIGs that would handle this much better

I'm far from an expert, but having been through the process (of teaching myself to arc weld), I think I have picked up a trick or two and I stand by my comments.

DamienS
13th Feb 2008, 12:52 PM
Wow.. Thanks for all the responses and advice, i shall read up on the links Grahame and get myself some heavier sections to practice on.:2tsup:

Thanks again,
Damien.

Uncle Bob
13th Feb 2008, 03:46 PM
I've found personally the best method for stick welding thin stuff is to do very quick welds. That is lay down a small weld about a second long, watch the glow die down (about 2-3 seconds) weld another short weld, let it cool down as above and just keep doing this. You can also fill in the blown holes with this method.
Hope this help you.

Fossil
13th Feb 2008, 06:49 PM
:((Hmm, was Grahame referring to us ... or this "bloke":?.

Graham was referring to the quote he pasted in the post with his comments.

I agree with his comments. :)

bsrlee
13th Feb 2008, 07:24 PM
As a largely self taught stick welder - practice, practice, practice. I got so I could weld 1.6mm sheet with 2.5mm rods and only the occasional blow out. You are not going to get either sound or neat looking welds just unboxing a rig & sticking a rod in - it all takes practice.

You have started out with the right idea - get a bunch of scrap bits of metal & try to weld them together. Chip out the slag, grind, see if it holds up to being whacked with a hammer. Repeat. Welding tube is a lot harder than welding sheet - I repaired a bunch of dining chairs for the local bowling club when Dad was a member - I think a lot of thin wall pipe has things added to the alloy to make it easier to form, like lead & high sulphur levels, which make it melt at a lower temperature - also fatigued areas are full of tiny cracks which stop the heat transferring.

If you have the opportunity, doing a short welding course at Tech. is also handy - a lot of them have 1-2 day courses aimed at hobby & art users.

MGR
13th Feb 2008, 07:31 PM
Hi Damien
Good luck learning welding techniques. You never stop learning with this stuff.
I did several TAFE welding courses at Swinburne in Melbourne a few years ago and found it a great experience. The speed of improvement that I was able to achieve was so much quicker than I could have done on my own. When I've been practicing on my own I found it's easy to just keep repeating mistakes. The teachers I had were great and I also learned heaps from the other folks doing the courses. It helps keep you motivated and moving on to new skills. These guys had decades of experience and didn't make you feel like a dill when things went wrong.
Starting on thicker stock and getting competent in basic fillet and butt welds before moving to thin wall tube is the go!
My 200amp ESAB mig welder is great at welding tube but I couldn't do it without the skills that those guys gave me.
Have fun with it
Cheers
Mike

Grahame Collins
13th Feb 2008, 07:48 PM
I do not believe I slighted any but the anonymous person or persons below.
I have re read the post a few times and to make it perfectly clear what I mean I'll re state it in another way.

I refer to advice offerred by a person who has very little real experience or skill in subject area they are talking about.
specifically the gentlemen that attack a thin bit of tube with the :

The wrong electrode type
The wrong amps setting
The wrong electrode angle
The wrong arc length
And completely the wrong attitude.


and then say.
Oh it's crap, it can't be done, you need a mig.Of course the retailers of migs will tell you they are the only thing to weld light gauge with. a must have. Below 1mm you will need a mig, I gree with that

Some of them, then buy the thing realizing gas rental is expensive and opt out for FCAW.
FCAW Flux Core arc welding or gasless is not suited for sheet metal.Why? because it runs too hotand the flux is acidic and corrodes under paint.I have posted pics in the past to prove this point.

Some of the hints offered here work for sure,but we can get people to the stage where they won,t burn any holes or at the least, not all that often.

I think its afe to saythere are more than a few blokes on this very forum who have altered their opinions on this subject and now are pretty capable with stick on thin wall tube.

I don't seek to denigrate or insult anyone. I get my jollies from helping people. I would sooner leave the forum than blue with anyone.I have seen that sort of nonsense wreck forums else where. If I get up your nose about something send me a PM and well sort it out together like adults.

peace brothers peace

Grahame

Grahame Collins
13th Feb 2008, 08:30 PM
The man wants to weld 2mm wall thickness tube .
It can and has been been done by our own forum members, We helped them to achieve it and we will do the same again.

I''ll enlarge on what I said above.

The wrong electrode type- One that penetrates too fiercely.6110 0r 6010 are no nos,,6112 or 6113's are ok.
Satincraft or one of its trade equivalents would do nicely
2 or 2.5mm is ok

The wrong amps setting- to suit above

The wrong electrode angle. The more perpendicular to the welding surface the greater penetration you will get. Lay the rod down sharply and the peno is almost end on the longitudinal flow of wall thickness. The technique is not to aim the arc at the cut edge on a joint but conversely to aim the arc the other way. In other words ,the cut edge should be on the side closest to you. It is easier to wash the arc back to the cut edge momentarily and whip back to the other side –which is better structurally suited to dissipating the heat

The wrong arc length –A long arc length increases the arc voltage to buggery thusly increasing the heat value in the arc pool – the last thing you want. Slightly higher amps, believe or not will stop the arc from failing or sticking at the shorter arc length.


And completely the wrong attitude. Well! nuff said about that elsewhere.Use the above techniques in conjunction with each other and success will follow.


Travel speed as has been stated does need to be quick as you can manage with out losing the arc.

I do agree with Wheelinaround about starting thick and working down. It a skill and technique which does need practice but can be mastered. Immediate failure on thin section gives a reason to give up initially when you do not yet understand that success is possible. Work down to your target thinness.

PS I just found the diagram. I would also add for you to minimise any gaps.Sometimes little feather left from cutoff make stand offs that leave a gap, file or grind off.

Nothing for it now but to have a go!
Regards
Grahame

wheelinround
14th Feb 2008, 07:22 AM
Damien one thing that hasn't been mention is that you can bow holes with Mig & Tig & Oxy just as easy or lay down a weld that looks :2tsup: but:doh: is shyte no hold it just sits there looking pretty on the surface with no penetration.

If you place your thin plate/tube on a steel bench it will absorb some of the heat and can make learning flow control easier.

Now of course if your trying to build a frame in situ welding in various positions makes it harder, doing vertical, overhead etc.

I applaud you interest in getting touch with the other side and seeing what they have to accomplish from your drawings. :2tsup:

Ray

Border boy
15th Feb 2008, 07:46 PM
Hi All,
like DamienS I'm embarking on a small welding project & have gone through a box of rods over the past week practicing on scrap. I'm using 2.5mm SHS mild steel and have found the info on this forum very educational. I've got a GMC arc welding machine & am finding it well up to the task of joining this metal stuff together. I've stopped blowing holes in my "T" joints by using the technique illustrated by Grahame - so thanks for that!! I'm finding that the key to success is to use amps in the lower recommended range for this type of joint (60A) and to crank the amps up to the higher end of range (85A) for the fillet weld around the corner of the flat joint. I'm using 2.5mm rods. I hope I'm on the right track - my welds are getting a lot neater.
I think Grahame has his hands full ATM with all that rain up in Mackay but just want to thank him & all for their contribution to this forum - back to practice:2tsup: