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Thread: Stick Welding
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22nd Jul 2005, 08:58 PM #16
The best advice I ever got was from a guy that had not ever seen me weld. As I was setting up he came over an said " SLOW DOWN and KEEP IT VERTICAL !!!! "
I say "but you have never seen me weld".
He says "don't care, you go to fast and don't keep the rod upright. Every amateur does"
He was absolutely right, that one tip made a big difference to the quality of my welds.Specializing in O positive timber stains
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22nd Jul 2005, 09:03 PM #17
Grahame, this is good stuff, greenie on the way!
I am a self professed welding numpty, and my welding sounds like bzzz, BRRRRRRRRR, twist - zap!
In other words, I tend to have the rod stuck to the workpiece a lot. Dunno why that is, but it attracts like it's magnetised or something. Next time I go out I'll try some of your tips.
Your description of excess voltage rings a bell. I seem to recall burning some holes through some 2.5mm box section I was welding last year, nasty business, lots of grinding and eventually hand filed it, bogged it and painted it - it wasn't a proud moment...
Tell me, are the instant darkening face shields worthwhile? I have a chepo standard face shield that likes to fall off while I work.
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22nd Jul 2005, 10:49 PM #18
Before you start the weld
Easy one Mick
What you mate means is the electrode when struck it takes an amount of time to generate the heat input to bring the parent metals and electrode to molten temperature – up to 6000 degrees Celsius. A comparison I make with students is to that of starting up a car on a freezing winter’s morning. While the motor does run it’s not until a minute or more when the motor arrives at required operating temperature.
If starting from an edge strike the arc and mark time dribbling over the lip or on the spot for say 1-2-3 –as long as it takes to say it . The electrode arc, held on the spot brings the job the job up to welding temp. On thinner section common sense will have you vary the time span.
If welding on a bead where you need to join up the start of a new bead to where the electrode ran out on the old one do the following. The bead will finish in a crater – a flat football shaped depression tapering back to the flat parent metal level -
Remember the striking block? Here’s an application for it. Strike your arc on it and while the electrode end is still red hot, quickly move it to a spot 8-10 mm downstream of your finish crater. Strike the arc here and lift up (3 X the electrode core wire diameter) and let it drop back to normal arc length. At the same time it is moved up to match the last ripples in the weld bead leading up to the crater. Time span say a second or two.
A practice or two and the casual observer won’t be able to tell where bead 1 ended and bead 2 began.
No worries
Grahame
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22nd Jul 2005, 11:00 PM #19
Tell me, are the instant darkening face shields worthwhile? I have a chepo standard face shield that likes to fall off while I work.[/QUOTE]
It is all relative to how much welding you do. Theres not much value if you are welding once a year. I had one for x ray stuff when an arc strike outside the weld bead was not tolerated. really you get what you pay for and a cheapy will fail well before you expect it to-just out of warranty ,if your luck is similair to mine.
Personally I think a good CIGWELD Hiderok (plastic helmet ) is the go. I have described how to tune them so a flick of the head drops them into position where the view slot is square to your eyes.
A cotton based skull cap under it stops your lid skid.
Hope this helps
Grahame
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24th Jul 2005, 12:43 AM #20
Weld trouble shooting
Trouble shooting your welding
You have just completed a welded project and my god, the welding; it looks like a seagull has the trots.
There are more slag holes than there is, welded bead. Chances are you have held too long an arc length and set the amperage too low. This combination would result an extra low amps and a distinct lack of penetration into the parent metal. As for a cure, there’s not a lot you can do but pick the slag out of the holes with a scriber or something sharp and pointy - grind the sorry mess out and increase the amperage and hold a MUCH closer arc. If you have used those blue crappy Craft rods you now know that they don’t like to weld over their own flux. Next time remember to save some job off cuts and do practice runs to get your amp settings right.
Basic welding electrical theory says that voltage up results in amperage down and vice versa.
On the other hand if the job is covered in excess spatter and you have tram tracks along the bead boundaries you have excess amperage and/or excess travel speed. If the job is going to flex at all, guess where the cracks will start from.
There’s stacks of really good info at aussieweld.com.au/arcwelding
I have attempted to cover what is not in the text books.
I hope the preceding comments will assist you in improving you welding. Many of your responses have helped me in becoming a better wood worker. I’ll try to answer your welding questions as they come up.
Thanks
Grahame
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24th Jul 2005, 01:10 AM #21Golden Member
- Join Date
- May 2003
- Location
- Perth WA
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- 526
Graheme
Great contribution to the board.Cheers,
Rod
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24th Jul 2005, 09:15 AM #22
Once again Grahame, real good stuff.
The Aussie weld link is a good one http://www.aussieweld.com.au/arcwelding/. As you said lots of info.Specializing in O positive timber stains
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24th Jul 2005, 09:17 AM #23Originally Posted by knucklehead
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2nd Aug 2005, 10:52 AM #24
Thank you Graham. Really informative, I think we owe you a beer or seven.
Question: I've been told that if the rods become damp they make welding even harder (for the unskilled that is). When it used to rain in Sydney mine would get damp in the shed, so I stuck them in the oven for 20 mins.
True or False
BodgyLast edited by Bodgy; 2nd Aug 2005 at 11:42 AM. Reason: Addit
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2nd Aug 2005, 11:54 AM #25
Thanks Graham [img]images/icons/icon7.gif[/img][img]images/icons/icon7.gif[/img]
Lots of info for everyone took me back a few years. Just like a refresher course.
Keep up the good posts. Greenie on the way
Sam
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2nd Aug 2005, 08:07 PM #26
Damp electrodes
Hi Bodgy
In answer to your question.
Damp electrode rods are not are problem of any great severity unless you happen to be X ray welding.
What happens is that H2O is reduced back to its constituents by a 6000 degree blast of welding arc temperature. Bingo! hydrogen and oxygen.Hydrogen is the nasty in highly stressed members potentially causing failures. For the ordinary backyard welder.No problem .Heat the electrodes up to 100 degrees C.
Hydrogen controlled electrodes should be kept in the oven after opening if you are using them for fair dinkum high structural strength purposes.
Grahame
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16th Aug 2005, 09:37 PM #27
Hi there
Have just found this thread and have really learnt a few things, I have bookmarked it for future use. Very informative and very easy to understand.
I have a Welder, it is a Transarc Tradesman. Just a question you might be able to help me with.
It has a high and low amperage, if I need to use the high amperage I have to transfer the cable from the low to high port. But to change the amperage, for both high and low it has a handle on the top which you turn for more or less amperage, At this point in time I have not needed to change. Possibly because I find that the low amperage is enough for what I need.
The question is, and probably a stupid one, but what would the high one be used for if it seems to do most jobs on the low amperage. I imagine it would be for heavy jobs. (probably answered my own question.)
Cheers
GrahamGirls often run through my mind, they dare not walk...
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17th Aug 2005, 06:52 PM #28
Transarc _Dual output terminals
Greyham
From One Greyham to another.
Actually its a good question not silly at all.
The tradesman is an light industrial level welder. As such one may be required to weld with stainless steel or Hydrogen controlled electrodes.
These elecrodes require a higher starting voltage- remember ! ? higher amps lower volts and viccy versa.
Usually poor unfortunates with a single output terminal will beat the S/S or L/H electrode tip to death trying to strike it.
This action will result in the end of electrode flux, cracking, spalling and breaking away .In turn , it makes the electrode in question even harder to strike, stick to the job, infuriate the operator and so it goes.
Some Low Hydrogen electrodes have a little bit over iron oxide placed at the tip of the electrode to enable easier striking.In addittion if the electrode is damp or wet, triple the hassle factor.
hang on to your tradesman as it can be wired for three phase if ever needed.
Grahame Collins
cheers
replying in between intermittent computer malfunctions
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19th Aug 2005, 03:43 AM #29
Bodgy, with damp electrodes (here it means any electrode!) I usually work on a steel stand. The top is sacrificial and is earthed. Just drag the electrode across the top for a second. Uses up a little electrode, but also gets it hot, which dries out the electrode and makes it ready to use.
If I don't do it, it's a nightmare to start a bead. If I do, zero problems.
Then again, I am stupid enough to actually weld cast iron with a standard electrode, and I know little enough to get away with it. Just once, but it works fine.
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3rd Aug 2007, 07:51 PM #30New Member
- Join Date
- Aug 2007
- Location
- Gold Coast
- Posts
- 2
hardened stressing cable
G'day, to anyone in the know. I was wanting to weld some stressing cable (used in construction, to pre-stress a concrete slab) to make a slide hammer for nailing in difficult to get places. Once the inner straight strand is removed from the centre, I need to weld around the outside to keep it together. The strands are about 5mm in diameter and this stuff is very hard. Any advice on electrode and amperage selection? Thanks.
Ian.Last edited by ian9toes; 3rd Aug 2007 at 07:53 PM. Reason: had 'constucting ' should've been 'construction'
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