Thread: Advice

Originally Posted by garfield

Yeah its a clean surface

Don't be discouraged by the rod getting stuck. This is normal for newbies and even less newbies if they have been out of practice for a while.

Here is how the TAFE demonstrator back in 1976 showed me how to learn how to strike an arc. Using 3 mm plate to practice on, turn the amps up about 10-15A above what is recommended for the rod you are using. The arc should strike easily like a big match. Then turn the amps down 2 - 3 amps at a time, and try starting the arc, till you reach a current where it starts to consistently catch the rod. Turn it back up 2-3 amps from there and practice starting the arc at that current. The demonstrator said we had to strike 20 arcs in a row without catching before we moved down in current. When you got the hang of it, drop it down some more, practice starting, do this until you reach the right current.

I remember it took me several hours of mucking about to be able to consistently strike an arc. Some people get the hang right away others take longer. I was really off because this young woman doing the same class got it first time! Sometimes I have gone years without using a welder and when I get back to it I have to up the amps a bit till I get my strike back again.

when starting a new rod l run it over some scrap metal this will heat the rod up then l move to the job
If you already lost the flux from the end of the rod you can keep running it over the scrap until you get down to the the flux ,dont do it to slow or it will stick again

Hi Garfield,

Why don't you go and buy youreld a DVD/Video on how to arc weld? A picture is worth a 1000 words - especially a moving one. Here is a site for a start.

http://smartflix.com/store/video/11/...Welding-Series

It appears to me - and don't take this the wrong way - but if you were given some tuition from a "top welder" why are you still asking all these questions? Its sounds to me that you don't have any confidence and you are not willing to give it a go and practice - practice makes perfect. It's no good seeking advice off everyone because its different strokes for different folks. You only have to look at all the professional golfers to notice they don't all have exactly the same swing? No, they don't yet they generally all get around the course within 10 strokes of one another. So I would suggest get a DVD (or lesser so a book) and follow the instructions. You could also try googling the subject matter and see what you can get for nothing. EBay is usually a good source of getting DVD's on certain subject matter.

MH

Originally Posted by Metal Head

It appears to me - and don't take this the wrong way - but if you were given some tuition from a "top welder" why are you still asking all these questions?

MH

I've only had one lesson off him, and I don't have access to him all the time and I like everyone's advice. People do things different to everybody else, and I think if you try them all you usually find one that suits you

P.S I want to have a go at welding this thin stuff, so should I buy some thin rods to give it a go?

Thanks

Well I tried to weld some tent poles today for my camp kitchen. I sort of got some ok, but it's bloody blotchy. I'm finding that my rods don't arc all that well. I turned down the amps to the 1.6 amps mark, but found it wasn't arcing so well so I turned it up to the 2 amps mark, it got a bit better it would arc ok and then some times really good but it also seemed to stick a lot. Is it maybe the amps are down too low - or could it be my rods?

You might be holding the rods to close to the steel, the rods must have an arc, which is created by having a gap between the rod and the steel. If the rod is too close, the arc is lost and the rod then fuses to the steel, which is the problem your having with the rods sticking.

Aim for a 2 to 4mm gap between the rod and the steel, if your getting blowouts decrease the gap or lower the amps. If sticking or dragging increase the gap or increase the amps.

Sometimes it gets stuck when I'm trying to arc the rod too.... maybe I'm a bit slow with my arcing. Is it a major NO, NO to hit the earth clamp to try and get the arc started? a few times I hit the clamp to get an arc going and now my clamp looks like it's got the chicken pox

Should I persist with 2.5mm rods for this thin stuff - or should I go the 1.6mm? Will it make much difference..?? I did actually get a good weld on .1% of my work It's a bloody expensive lesson though. I did blow a couple of holes, but found that when I did that that the arc was quite good and it was really red which kept the arc going enough for me to patch up what I'd blown through.

One more thing - If I have a couple of really annoying looking blotchy welds, do I just grind them and then try and weld them better?

Ive asked before where abouts in sydney are you,if time permits and your interested I may be able to help.

Originally Posted by pipeclay

Ive asked before where abouts in sydney are you,if time permits and your interested I may be able to help.

Sorry pipeclay, I mustn't have seen your reply. I'm in western sydney.... Blacktown way

Can you not weld over slag? If you have just welded something is it important to knock the slag off before welding next to it?

And how important is it to wire brush it?

Originally Posted by garfield

Is it a major NO, NO to hit the earth clamp to try and get the arc started? a few times I hit the clamp to get an arc going and now my clamp looks like it's got the chicken pox

Hi Garfield.
Lets put it this way. Apart from the visual aspect of the clamp you are overheating the spring in the a clamp and reducing the tension of the grip. This affects the flow of electricity in the circuit which in turn affects your weld.Spatters from the arc get under the clamp reducing the area contact and welding gets even worse.
Clean up the clamp and the contact area under it- to start with.

If you are still welding on tent poles,they can be as thin as paper and one of the most difficult things to weld anyway. Get some 50 x5 or 6 mm thick flat 70 to 100 long and run parallel beads.

As the other fellows suggest I would be perfecting my welds.You have several hours of practice ahead of you. From assistance of your gun welder ,you should already have a visual idea of what you are trying to achieve.

The striking block of scrap is the way to go.
To help what the gun probably showed you.
A good bead should be even height ,even width and have a consistent ripple that looks like a crescent.If the pattern is arrow shaped -you are traveling too fast. Consistency is the name of the game here.Slag inclusions and holes generally indicate too long an arc.

Don't fixate on the specific numerical arc setting.It will vary with grid load through out the day.What goes into the machine at the plug, affects what you will get out of it. Ignore the numbers and work out what you need, to be hotter or colder or stay the same. As the metal overheats you will need to reduce amps slightly.

Get SAVAGE

Speed -Speed of travel
Angle -Determines depth of penetration into the metal
Volts - Arc length determines volts and heat value into the weld pool- About that of the core wire
Amps-The amp setting to suit the electrode diameter.
Gauge -The electrode diameter in metric measure to suit your plate thickness
Electrode-The correct type of electrode for the work 6012 0r 6013

Work backwards from Electrode end of the anagram.
The above are the basics required to achieve a reasonable weld.You won't get there p***ing around on ultra thin materials to learn upon. I have taught hundreds of people to weld and they all take between -4 to 8hrs to get up to speed on a a piece of reasonably thick plate -say 6mm to start. To do otherwise will waste your time and effort.
Perfect your technique first, OK?

Keep practicing

Grahame

Originally Posted by Grahame Collins

The striking block of scrap is the way to go.

Get SAVAGE

Speed -Speed of travel
Angle -Determines depth of penetration into the metal
Volts - Arc length determines volts and heat value into the weld pool- About that of the core wire
Amps-The amp setting to suit the diameter
Gauge -The electrode diameter in metric measure to suit your plate thickness
Electrode-The correct type of electrode for the work 6012 0r 6013

Grahame

Thanks Grahame. Does the striking plate need to be earthed?

Also, do you think it would make that much difference if i used a thinner rod.... say a 1.6mm rod as against the 2.5 i'm using now?

Hi Garfield,
The striking plate must be earthed otherwise you could not make an arc strike on it.

It can be just a bit of scrap clamped between the table /work surface or a dedicated plate tacked on a bit of round with a little 50 x50 x 6 plate tacked on a bit of 10mm round (kinda like a 1 legged table.)
This is assuming you have a steel table top-otherwise clamp the throw away plate directly to the work.

Using strike plate gets the electrode up and running .One strikes the electrode and gets its running stable for a second or two and then jumps across while its still red hot.

The end of the electrode is maintained in the gun barrel shape shape necessary to start the arc. If the electrode cover flux is chipped away thats where the problems come from sticking on a cold start.
Forget the smaller rods until you get good results from your 2.5mm rods.Otherwise you are all over the place settings wise and its consistency in all the aspects of the welding process, one is aiming for.

Time for work
Grahame

Thanks Grahame....

One more thing mate, how important is it to chip off the slag? will it be a defect weld if i was to re-weld over a bead that hasn't had the slag chipped off? and what about the wire brush... is that necessary?