- Thread starter brendan h
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zzr1200
Working at 650 ft on open steel work.
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Yes...
The amount of hydrogen included in the weld, is in direct ratio to the dryness of the rod to start with, the dryer the rod the better the weld, ie:instant strength welds.
Rutile rods (6013) are not as picky but should still be used dry from the packet, rutile rods can obtain the same strength weld as low/highs but you have to wait for about 10 days for the hydrogen to dissipate from the weld, if I remember correctly...
I use a baby belling oven to dry my rods, purchased off fleabay for 30 quid brand new, better than 200-00+ for a proper rod oven
Drains
Yeah, nah.
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Haud on there. If the rods are straight out of the unbroken packet, you're fine, just weld away. Otherwise, as stated, dry - but according to the instructions on the packet.
Some rods you don't need to worry about at all, eg 6010, 6011's. But they can crack easily if you don't put a hot pass in to drive out the hydrogen.
6013's can perform well as long as they are not damp.
ZZR - How can 60xx rods become as strong as 70xx rods?, the 60-70-also 80 code denotes strength.
Also, a 7016/8 is a sod to use if not properly dried, regardless of the weld properties.
And, Brendan, you're not putting the rods in the oven to preheat them, but to dry the flux. A warm rod will often give a better strike though.
Some rods you don't need to worry about at all, eg 6010, 6011's. But they can crack easily if you don't put a hot pass in to drive out the hydrogen.
6013's can perform well as long as they are not damp.
ZZR - How can 60xx rods become as strong as 70xx rods?, the 60-70-also 80 code denotes strength.
Also, a 7016/8 is a sod to use if not properly dried, regardless of the weld properties.
And, Brendan, you're not putting the rods in the oven to preheat them, but to dry the flux. A warm rod will often give a better strike though.
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agreed Simon you should store all rods in dry conditions, and If lo-His are kept in the dry there is no need for redrying, if your to WPS or even good practice kept in a quiver before use and only pulled a few at a time,
7018/16 live in the house all others are as good as kept in the workshop.....
Most lo-his BTW tend to prefer a D/C weld.... Or A/C on higher OVCs this is often the cause of bad striking, or even better a Lorch Inverter running hot start technology (you can leave that with me if you like Matt
)
7018/16 live in the house all others are as good as kept in the workshop.....
Most lo-his BTW tend to prefer a D/C weld.... Or A/C on higher OVCs this is often the cause of bad striking, or even better a Lorch Inverter running hot start technology (you can leave that with me if you like Matt
)
Drains
Yeah, nah.
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even better a Lorch Inverter running hot start technology (you can leave that with me if you like Matt
When I was a kid, living in Nottingham, some of us were selected to "test drive" some new model Raleigh bikes. I was convinced we could keep them after... Matt?? Pleeeeze...
zzr1200
Working at 650 ft on open steel work.
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- Glapwell, Chesterfield, Derbyshire, UK
Simondrains, I haven't been to college for a very long time and I may well have forgotten and if I'm wrong I will stand corrected.
Low/high rods produce virtually full instant strength welds that require very little time to allow the hydrogen gas to peculate out of the weld provided they are stored dry and used as instructed. This is shown by different amounts of hydrogen produced depending on rod heating conditions for the same rod (hence low hydrogen/high strength).
Rutile on the other hand have a higher amount of hydrogen gas produced in the arc shield (due to the higher vegetable content of the flux shield?) this then peculates out of the weld over about 10/14 days allowing the weld to obtain full strength.
brendan h, didn't state which low highs he possibly intended to use only what appeared to be a general question on low/highs requiring to be heated or used straight out of the packet.
At college we were told always to heat low/high rods to obtain maximum strength welds.
As I said "if I remember correctly" its at least 15 years since I was at college and welding has never been my main way of making a living, although has played a part at times.
Lo Hys (7018) packed in Vacuum Packs dont need drying if used straight from a previously unopened pack.
7018's in cardboard boxes may need drying if they are old or have been exposed to moisture.
There are 2 types of moisture, chemically combined and "loose". Chemically combined is, as you would expect, part of the mineral molecule (minerals make up the coating). The loose moisture is picked up from the atmosphere. The loose moisture can be removed at 110oC but the combined needs at least 350oC for 1 hour.
Unless you are doing critical work it is unlikely that you will need to dry 7018s at all but they do strike up better when warm (thats why they have black ends).
Hydrogen cracks are unlikely to occur unless you have very high restraint / very thick plate and/or low alloy steel. It does happen but not very often.
Rutiles only need drying if you are getting start porosity. You can rough dry them by shorting them out (like a stuck rod).
7018's in cardboard boxes may need drying if they are old or have been exposed to moisture.
There are 2 types of moisture, chemically combined and "loose". Chemically combined is, as you would expect, part of the mineral molecule (minerals make up the coating). The loose moisture is picked up from the atmosphere. The loose moisture can be removed at 110oC but the combined needs at least 350oC for 1 hour.
Unless you are doing critical work it is unlikely that you will need to dry 7018s at all but they do strike up better when warm (thats why they have black ends).
Hydrogen cracks are unlikely to occur unless you have very high restraint / very thick plate and/or low alloy steel. It does happen but not very often.
Rutiles only need drying if you are getting start porosity. You can rough dry them by shorting them out (like a stuck rod).
Drains
Yeah, nah.
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Hey ZZR. I don't dispute that a rutile will gain full strength after the hydrogen has leeched out, only that a 60xx will ever be as strong as a 70xx, as those numbers refer to the tensile strength in pounds per square inch (x1000).
It's not an issue that will affect many, although there are occasions when welding with higher spec applications (tractor/loading/lifting gear, for instance) when 70xx's would be recommended.
With you on most of what you said though!
It's not an issue that will affect many, although there are occasions when welding with higher spec applications (tractor/loading/lifting gear, for instance) when 70xx's would be recommended.
With you on most of what you said though!
shenion
Tool Pack Rat
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I was going to use an old toaster overn as a drying oven. I ended finding one on ebay cheap. They usually go for at least $100+shipping for small ones, but one seller put up near a dozen of them. I got the last for about $60 with shipping.
My 7018's are stored in PVC pipes with end caps. In the bottom of each is a silica gel bag.
My garage is wet/humid. I noticed porosity in some test welds with them, so looked for a rod oven.
I have some Lincoln and WeldIt 7014 rods. They look and work the same as 7018's (with low to medium penetration.) Nowhere on the package do they specify they need to be kept dry. sounds like a good alternative especially if you use a deep penetration rod for a root.
My 7018's are stored in PVC pipes with end caps. In the bottom of each is a silica gel bag.
My garage is wet/humid. I noticed porosity in some test welds with them, so looked for a rod oven.
I have some Lincoln and WeldIt 7014 rods. They look and work the same as 7018's (with low to medium penetration.) Nowhere on the package do they specify they need to be kept dry. sounds like a good alternative especially if you use a deep penetration rod for a root.
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TBH a 7014 would probably be a good alternative to 7018/16, same tensile strength but - the need to be kept as a low high, As others have mentioned theres probably not many members that really need to worry about such issues as hydrogen or Haz cracking etc, and I only really as a rule use 6013s on "standard" type work then use lo His on stressed thick plate, lifting gear or WPS work.....
Psssst Simon I think we safe I haven't heard from Matt I reckon hes forgot we've even got em.....
English Steve
Senior Bumpkin
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As an apprentice (many years ago) we made a rod oven by fabricating a steel box with a bit of insulation in it, then wiring in a light bulb. The bulb was permanently on and kept everything in the box toasty. Might be OK for home just to keep the worst of the damp out.
one to heat the liquid, it get's bloody hot!
Woody.v8
Blue gluer
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A's and W's can be confuzzleing
Hehe, it's cos we're always talking about welders in terms of amps
Not much use in me editing my post now seeing as you've quoted me but I will anyway
Woody.v8
Blue gluer
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Hehe, it's cos we're always talking about welders in terms of amps
Not much use in me editing my post now seeing as you've quoted me but I will anyway
Im only messing about woz
We all make mistakes
English Steve
Senior Bumpkin
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If anyone does want to build a rod oven using a bulb for heat, you will have to get a wriggle-on before they ban 40W ordinary filament bulbs. I imagine the low energy bulbs won't give off anywhere near as much heat so probably won't work.
