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Posted by Alan Andrews on March 23, 2008, 10:11 pm
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Thanks much. I think it's safe to say that my application falls into the
"non-critical" category. What with the expense of low hydrogen nowadays,
though, one needs to have a really good reason for throwing away undamaged
stick electrodes.
Thanks again,
Alan
> The Lincoln "Stick Electrode Product Catalog"
> http://content.lincolnelectric.com/pdfs/products/literature/c210.pdf
> page 46
>
> has this to say
> <start quote>
> Re-drying Low Hydrogen Electrodes
> Re-drying, when done correctly, restores the electrodes’ ability to
> deposit quality welds. Proper re-drying temperature depends upon the
> electrode type and its condition.
>
> One hour at the listed final temperature is satisfactory. DO NOT
> dry electrodes at higher temperatures. Several hours at lower
> temperatures is not equivalent to using the specified
> requirements.
>
> Electrodes of the E8018 and higher strength classifications
> should be given no more than three 1-hour re-dries in the 700° -
> 800°F (370° - 430°C) range. This minimizes the possibility of
> oxidation of alloys in the coating resulting in lower than normal
> tensile or impact properties.
>
> Any low hydrogen electrode should be discarded if excessive redrying
> causes the coating to become fragile and flake or break
> off while welding, or if there is a noticeable difference in handling
> or arc characteristics, such as insufficient arc force.
>
> Electrodes to be re-dried should be removed from the can and
> spread out in the oven because each electrode must reach the
> drying temperature.
>
>
> Electrodes which have come in direct contact with water or which have been
> exposed to high humidity 180° - 220°F for one hour, then 650° - 750°F for
> one hour.
>
> <End quote>
>
> That temp schedule is not achievable in a standard rod oven, hence the
> comments you get from the various sources.
>
> Should you use it? If this was a critical application, toss the rod. If it
> is not a critical application, you can use your judgment about drying the
> rod per the schedule, then deal with "if there is a noticeable difference
> in handling or arc characteristics, such as insufficient arc force". In
> most cases, the problems with lousy rod far outweigh the cost of the rod,
> not to mention the cost of materials and the time to weld.
>
>
>
> Alan Andrews wrote:
>> Some time ago I purchased a 50# box of E7018 Hobart electrodes. I'm not
>> a professional welder, nor do I have occasion to do that much welding,
>> which means that I had an open box of low hydrogen exposed to atmospheric
>> humidity for quite some time, like a year.
>>
>> I'm in the midst of building a custom steel fence on the front of my
>> residence property and some of the welding will be done with low
>> hydrogen. At the local welding supply I mentioned in passing the story
>> about the opened rods and asked if low hydrogen rods actually "got old,"
>> like I'd heard for ever. They indicated that they did indeed degrade,
>> such so that they couldn't even be reconditioned in an oven.
>>
>> When I got home I called Hobart and spoke with a technician who said that
>> once low hydrogen was exposed to the atmosphere, it immediately started
>> *irreversibly* degrading, and that, yes, re-drying them in an oven didn't
>> help. I said that that would seem to indicate that a chemical reaction
>> had taken place (with what I thought was rather inert inorganic material
>> (rutile, for instance)) and he, sorta handwavingly (if that's a word)
>> said, yeah.
>>
>> To confuse and confound the question, I found a document on the Web from
>> Lincoln Electric that indicated that Lincoln E7018 could indeed be
>> reclaimed by drying in an oven
>> (http://www.jflf.org/pdfs/papers/fabguide.pdf, p. 7). So...what IS the
>> story on storing an open quanity of 7018 for protracted periods, in out
>> of the weather (my garage, for instance), but nonetheless exposed to
>> Southern-style humidity.
>>
>> Thanks,
>> Alan
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Posted by Grant Erwin on March 23, 2008, 4:12 pm
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Alan Andrews wrote:
> Some time ago I purchased a 50# box of E7018 Hobart electrodes. I'm not a
> professional welder, nor do I have occasion to do that much welding, which
> means that I had an open box of low hydrogen exposed to atmospheric humidity
> for quite some time, like a year.
>
> I'm in the midst of building a custom steel fence on the front of my
> residence property and some of the welding will be done with low hydrogen.
> At the local welding supply I mentioned in passing the story about the
> opened rods and asked if low hydrogen rods actually "got old," like I'd
> heard for ever. They indicated that they did indeed degrade, such so that
> they couldn't even be reconditioned in an oven.
>
> When I got home I called Hobart and spoke with a technician who said that
> once low hydrogen was exposed to the atmosphere, it immediately started
> *irreversibly* degrading, and that, yes, re-drying them in an oven didn't
> help. I said that that would seem to indicate that a chemical reaction had
> taken place (with what I thought was rather inert inorganic material
> (rutile, for instance)) and he, sorta handwavingly (if that's a word) said,
> yeah.
>
> To confuse and confound the question, I found a document on the Web from
> Lincoln Electric that indicated that Lincoln E7018 could indeed be reclaimed
> by drying in an oven (http://www.jflf.org/pdfs/papers/fabguide.pdf, p. 7).
> So...what IS the story on storing an open quanity of 7018 for protracted
> periods, in out of the weather (my garage, for instance), but nonetheless
> exposed to Southern-style humidity.
Alan, stop a bit and think about what you are asking. You are building a
fence! The welds you need on your fence need be little more than decent tacks.
Unless you are incorporating a heavy gate, there is little stress on a fence
at any time. You have no need of the ultimate failing strength of 70000 pounds
that you get from perfectly maintained 7018 rods.
I once acquired quite a bit (~100 pounds) of old 7018 rod. It was open, dumped
into a large cardboard box, and would have never been suitable for a certified
weld. Yet I welded with it, making dozens of useful items. Were they as strong
as they would have been if I'd bought new rod each time and kept it in an oven?
No. Were they plenty strong enough? Absolutely.
You have already gotten conflicting opinions from Hobart and Lincoln, why would
anything posted on a newsgroup carry any more weight than those?
I would stop worrying and weld up your fence with your rod.
there .. that was worth at LEAST what you paid for it!
Grant Erwin
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Posted by Private on March 23, 2008, 5:53 pm
Please log in for more thread options
> Alan Andrews wrote:
>> Some time ago I purchased a 50# box of E7018 Hobart electrodes. I'm not
>> a professional welder, nor do I have occasion to do that much welding,
>> which means that I had an open box of low hydrogen exposed to atmospheric
>> humidity for quite some time, like a year.
>>
>> I'm in the midst of building a custom steel fence on the front of my
>> residence property and some of the welding will be done with low
>> hydrogen. At the local welding supply I mentioned in passing the story
>> about the opened rods and asked if low hydrogen rods actually "got old,"
>> like I'd heard for ever. They indicated that they did indeed degrade,
>> such so that they couldn't even be reconditioned in an oven.
>>
>> When I got home I called Hobart and spoke with a technician who said that
>> once low hydrogen was exposed to the atmosphere, it immediately started
>> *irreversibly* degrading, and that, yes, re-drying them in an oven didn't
>> help. I said that that would seem to indicate that a chemical reaction
>> had taken place (with what I thought was rather inert inorganic material
>> (rutile, for instance)) and he, sorta handwavingly (if that's a word)
>> said, yeah.
>>
>> To confuse and confound the question, I found a document on the Web from
>> Lincoln Electric that indicated that Lincoln E7018 could indeed be
>> reclaimed by drying in an oven
>> (http://www.jflf.org/pdfs/papers/fabguide.pdf, p. 7). So...what IS the
>> story on storing an open quanity of 7018 for protracted periods, in out
>> of the weather (my garage, for instance), but nonetheless exposed to
>> Southern-style humidity.
>
> Alan, stop a bit and think about what you are asking. You are building a
> fence! The welds you need on your fence need be little more than decent
> tacks.
> Unless you are incorporating a heavy gate, there is little stress on a
> fence
> at any time. You have no need of the ultimate failing strength of 70000
> pounds
> that you get from perfectly maintained 7018 rods.
>
> I once acquired quite a bit (~100 pounds) of old 7018 rod. It was open,
> dumped
> into a large cardboard box, and would have never been suitable for a
> certified
> weld. Yet I welded with it, making dozens of useful items. Were they as
> strong
> as they would have been if I'd bought new rod each time and kept it in an
> oven?
> No. Were they plenty strong enough? Absolutely.
>
> You have already gotten conflicting opinions from Hobart and Lincoln, why
> would
> anything posted on a newsgroup carry any more weight than those?
>
> I would stop worrying and weld up your fence with your rod.
>
> there .. that was worth at LEAST what you paid for it!
>
> Grant Erwin
I agree.
Unless we are talking about rods that have been soaked or have been exposed
to wet atmosphere for a very long time and/or bear evidence of deterioration
due to heavy rust or white powder deposits on the coating. Most/many low
hydrogen rods have lime and other hygroscopic materials in the coating and
will attract moisture and if severe it can make them unpleasant to weld and
with poor quality results.
Low hydrogen rods (and SA Lincoln welders) were developed to limit hydrogen
embitterment (WW11 Liberty ships) which is mostly a problem of high duty
cycle loading and is similar to fatigue. It often manifests itself by
underbead cracking and is sometimes the problem when people point to a crack
beside a weld and comment that the weld was stronger than the parent metal.
AFAIK, most plain steel is only good for ~45k tensile and normal rods like
xx10, xx11, xx13, xx14 are not low hydrogen but still make lots of
satisfactory and serviceable welds.
Unless this is a code fence built with high tensile steel you are unlikely
to have any problems even if you do not dry your rods at all, but a simple
drying for ~1hr in a kitchen range @ 350-450 (spread then out on the wire
rack) is unlikely to do any harm and will probably improve their
performance. Only dry them as you need them as repeated drying is not
desirable. The place where it is most important to use new rods from a
sealed container is when welding pressure pipe or high strength steels
subject to high loads and cycles and where failure will have consequences.
I would be very careful of the condition of rods used for welding anything
critical and particularly trailer hitches or suspensions for on road use.
If it is not possible to keep you rods in a warm dryer, it is worthwhile to
keep them in containers that limit the contact with air, and to open new
boxes when doing critical work.
Just my .02, YMMV
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Posted by Alan Andrews on March 23, 2008, 10:12 pm
Please log in for more thread options "...or white powder deposits on the coating."
Funny you should mention that. They DO have a white powdery residue on
them. That's bad, I take it?
>
>> Alan Andrews wrote:
>>> Some time ago I purchased a 50# box of E7018 Hobart electrodes. I'm not
>>> a professional welder, nor do I have occasion to do that much welding,
>>> which means that I had an open box of low hydrogen exposed to
>>> atmospheric humidity for quite some time, like a year.
>>>
>>> I'm in the midst of building a custom steel fence on the front of my
>>> residence property and some of the welding will be done with low
>>> hydrogen. At the local welding supply I mentioned in passing the story
>>> about the opened rods and asked if low hydrogen rods actually "got old,"
>>> like I'd heard for ever. They indicated that they did indeed degrade,
>>> such so that they couldn't even be reconditioned in an oven.
>>>
>>> When I got home I called Hobart and spoke with a technician who said
>>> that once low hydrogen was exposed to the atmosphere, it immediately
>>> started *irreversibly* degrading, and that, yes, re-drying them in an
>>> oven didn't help. I said that that would seem to indicate that a
>>> chemical reaction had taken place (with what I thought was rather inert
>>> inorganic material (rutile, for instance)) and he, sorta handwavingly
>>> (if that's a word) said, yeah.
>>>
>>> To confuse and confound the question, I found a document on the Web from
>>> Lincoln Electric that indicated that Lincoln E7018 could indeed be
>>> reclaimed by drying in an oven
>>> (http://www.jflf.org/pdfs/papers/fabguide.pdf, p. 7). So...what IS the
>>> story on storing an open quanity of 7018 for protracted periods, in out
>>> of the weather (my garage, for instance), but nonetheless exposed to
>>> Southern-style humidity.
>>
>> Alan, stop a bit and think about what you are asking. You are building a
>> fence! The welds you need on your fence need be little more than decent
>> tacks.
>> Unless you are incorporating a heavy gate, there is little stress on a
>> fence
>> at any time. You have no need of the ultimate failing strength of 70000
>> pounds
>> that you get from perfectly maintained 7018 rods.
>>
>> I once acquired quite a bit (~100 pounds) of old 7018 rod. It was open,
>> dumped
>> into a large cardboard box, and would have never been suitable for a
>> certified
>> weld. Yet I welded with it, making dozens of useful items. Were they as
>> strong
>> as they would have been if I'd bought new rod each time and kept it in an
>> oven?
>> No. Were they plenty strong enough? Absolutely.
>>
>> You have already gotten conflicting opinions from Hobart and Lincoln, why
>> would
>> anything posted on a newsgroup carry any more weight than those?
>>
>> I would stop worrying and weld up your fence with your rod.
>>
>> there .. that was worth at LEAST what you paid for it!
>>
>> Grant Erwin
>
>
> I agree.
>
> Unless we are talking about rods that have been soaked or have been
> exposed to wet atmosphere for a very long time and/or bear evidence of
> deterioration due to heavy rust or white powder deposits on the coating.
> Most/many low hydrogen rods have lime and other hygroscopic materials in
> the coating and will attract moisture and if severe it can make them
> unpleasant to weld and with poor quality results.
>
> Low hydrogen rods (and SA Lincoln welders) were developed to limit
> hydrogen embitterment (WW11 Liberty ships) which is mostly a problem of
> high duty cycle loading and is similar to fatigue. It often manifests
> itself by underbead cracking and is sometimes the problem when people
> point to a crack beside a weld and comment that the weld was stronger than
> the parent metal. AFAIK, most plain steel is only good for ~45k tensile
> and normal rods like xx10, xx11, xx13, xx14 are not low hydrogen but still
> make lots of satisfactory and serviceable welds.
>
> Unless this is a code fence built with high tensile steel you are unlikely
> to have any problems even if you do not dry your rods at all, but a simple
> drying for ~1hr in a kitchen range @ 350-450 (spread then out on the wire
> rack) is unlikely to do any harm and will probably improve their
> performance. Only dry them as you need them as repeated drying is not
> desirable. The place where it is most important to use new rods from a
> sealed container is when welding pressure pipe or high strength steels
> subject to high loads and cycles and where failure will have consequences.
> I would be very careful of the condition of rods used for welding anything
> critical and particularly trailer hitches or suspensions for on road use.
>
> If it is not possible to keep you rods in a warm dryer, it is worthwhile
> to keep them in containers that limit the contact with air, and to open
> new boxes when doing critical work.
>
> Just my .02, YMMV
>
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Posted by RoyJ on March 23, 2008, 10:30 pm
Please log in for more thread options A light powdery residue is not too alarming (as long as you are not
trying to be code compliant) but major white fuzz is not good. Any rod
where the flux cracks or falls off is completely worthless.
Alan Andrews wrote:
> "...or white powder deposits on the coating."
>
> Funny you should mention that. They DO have a white powdery residue on
> them. That's bad, I take it?
>
>
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> http://content.lincolnelectric.com/pdfs/products/literature/c210.pdf
> page 46
>
> has this to say
> <start quote>
> Re-drying Low Hydrogen Electrodes
> Re-drying, when done correctly, restores the electrodes’ ability to
> deposit quality welds. Proper re-drying temperature depends upon the
> electrode type and its condition.
>
> One hour at the listed final temperature is satisfactory. DO NOT
> dry electrodes at higher temperatures. Several hours at lower
> temperatures is not equivalent to using the specified
> requirements.
>
> Electrodes of the E8018 and higher strength classifications
> should be given no more than three 1-hour re-dries in the 700° -
> 800°F (370° - 430°C) range. This minimizes the possibility of
> oxidation of alloys in the coating resulting in lower than normal
> tensile or impact properties.
>
> Any low hydrogen electrode should be discarded if excessive redrying
> causes the coating to become fragile and flake or break
> off while welding, or if there is a noticeable difference in handling
> or arc characteristics, such as insufficient arc force.
>
> Electrodes to be re-dried should be removed from the can and
> spread out in the oven because each electrode must reach the
> drying temperature.
>
>
> Electrodes which have come in direct contact with water or which have been
> exposed to high humidity 180° - 220°F for one hour, then 650° - 750°F for
> one hour.
>
> <End quote>
>
> That temp schedule is not achievable in a standard rod oven, hence the
> comments you get from the various sources.
>
> Should you use it? If this was a critical application, toss the rod. If it
> is not a critical application, you can use your judgment about drying the
> rod per the schedule, then deal with "if there is a noticeable difference
> in handling or arc characteristics, such as insufficient arc force". In
> most cases, the problems with lousy rod far outweigh the cost of the rod,
> not to mention the cost of materials and the time to weld.
>
>
>
> Alan Andrews wrote: