Eric_Phillips
Platinum Member
I am in the process of building some forks for my FEL. I am getting some undercutting when I weld the pieces together. Is this a technique thing or do I have it set too hot. I am using AC stick.
Welding undercutting
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BHD
Veteran Member
a little hot is my guess, it may be some rod choice (type and size of rod diameter) , and technique,
prepare the metal correctly and depending on the rod of choice, use the proper heat and weld proper speed and weave,
most of the time I find that when your using a rod that is not "hot" deep penetrating, one has the tendency to up the amps to get penetration of the weld, but depending on the rod and the speed of welding of the bead one can undercut the steel being welded,
some rods I think have more of a tendency to undercut than others, as well,
not really the rod but the way the rod is used.
moving to fast and not letting it fill properly is another possibility,
I know we (I) get lazy and some times turn up the heat when in a hurry to by pass the proper beveling of the area to be welded,
multiple passes are fine, one does not need to build the weld up in one pass.
some times the angle in which the rod is held can contribute as well,
if the metal is extremely cold may not benefit as well as the weld may cool faster than desired,
it has been a long time since I used straight AC, but I know I have done enough under cutting, in my day when starting out, and I can do it on DC as well,
prepare the metal correctly and depending on the rod of choice, use the proper heat and weld proper speed and weave,
most of the time I find that when your using a rod that is not "hot" deep penetrating, one has the tendency to up the amps to get penetration of the weld, but depending on the rod and the speed of welding of the bead one can undercut the steel being welded,
some rods I think have more of a tendency to undercut than others, as well,
not really the rod but the way the rod is used.
moving to fast and not letting it fill properly is another possibility,
I know we (I) get lazy and some times turn up the heat when in a hurry to by pass the proper beveling of the area to be welded,
multiple passes are fine, one does not need to build the weld up in one pass.
some times the angle in which the rod is held can contribute as well,
if the metal is extremely cold may not benefit as well as the weld may cool faster than desired,
it has been a long time since I used straight AC, but I know I have done enough under cutting, in my day when starting out, and I can do it on DC as well,
Rod type and heat.
6010 & 6011 are deep penetrating
6013 & 7018 are low penetrating
A good inbetween rod is the 7014. High tensile strength, super easy to weld, and medium penetration.
The 7014 is my favorite rod.
On my Miller Wildcat I run the 1/8" 7014 at 140 amps. The 3/32" works well at 90 amps.
6010 & 6011 are deep penetrating
6013 & 7018 are low penetrating
A good inbetween rod is the 7014. High tensile strength, super easy to weld, and medium penetration.
The 7014 is my favorite rod.
On my Miller Wildcat I run the 1/8" 7014 at 140 amps. The 3/32" works well at 90 amps.
OP
Eric_Phillips
Platinum Member
Thanks for the help. I have to admit I have no idea what the rod was I was using. I got the welder when my wife's uncle passed away and he had some rod laying around. It was in an opened package but with no identification on it and the rod itself had nothing stamped on it. That is all used up now and I do have some 6013 I bought. I will try going over the top with that to see if it helps.
Never use old and/or damp rods. Always keep the rods in a cool dry place, preferably in a sealed rod box/canister. The red or blue rod "tubes" are about $15.
The flux coating will wick up moisture and not weld correctly.
Me I use an old fridge to store my rods in and in the event of them being damp I place them in the oven at about 50 deg C to dry,or if I am in a hurry just stick the rod for 10-15 sec or until the steam disappears.
Stock
ps have being nosing around for a while
Stock
ps have being nosing around for a while
pat32rf
Veteran Member
The Lincoln rep used to tell us that the low hydrogen rods are the ones that tend to have problems with moisture. Regular rod isn't as touchy and weld ok once they get dry, they are just a little harder to use when dripping wet....
jimmer2880
Platinum Member
....
A good inbetween rod is the 7014. High tensile strength, super easy to weld, and medium penetration.
The 7014 is my favorite rod.
On my Miller Wildcat I run the 1/8" 7014 at 140 amps. The 3/32" works well at 90 amps.
I'm no welder, but I have done a fair amt of welding. 7014 is my favorite also.
Gary Fowler
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I prefer the 6010 (6011 for AC) and 7018 myself. The 7014 are easy to run, but seem to be a bit on the brittle side. 7018 are much more ductile, but they do require a bit more skill to run. BTY, undercutting is more technique than amperage, with the correct technique, a proper weld can be made even if the amperage is a little too high. Proper setting of machine, right rod for the situation and a skilled user will make a beautiful weld. I have seen ugly welds that function just as well as pretty ones though, after all on the farm, we are not required to meet any specification or Code except our own personal requirements.
Eagle Dude
Member
Horriable Fright has tubed Rod Holders (Orange) with a sealing gasket for $5.99.
LD1
Epic Contributor
Another vote for 7014 for me.
Back in the day, my dad always swore by 6013. Super easy to weld.
Myself, after trying different types of rods, I liked the 7014. It welds as easy as 6013 and has 10,000psi more tensile strength. I now have him hooked on it as well. I have never noticed it being brittle.
I never had any luck with 7018 though. Maybe it is the welder. It is just an old craftsman and I'm not sure wether it's ac or dc.
To everyone that swears by the 7018 as being the ultimate rod, for the home DIY'er, a good weld with 7014 will hold better than a poor weld with 7018.
Back in the day, my dad always swore by 6013. Super easy to weld.
Myself, after trying different types of rods, I liked the 7014. It welds as easy as 6013 and has 10,000psi more tensile strength. I now have him hooked on it as well. I have never noticed it being brittle.
I never had any luck with 7018 though. Maybe it is the welder. It is just an old craftsman and I'm not sure wether it's ac or dc.
To everyone that swears by the 7018 as being the ultimate rod, for the home DIY'er, a good weld with 7014 will hold better than a poor weld with 7018.
BigEddy
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Couple comments
7018 is a Lo-Hydrogen rod that is a medium to deep penetrating rod (Not low penetrating as stated earlier). Probably one of the highest volume rods of all. As a Lo-Hydrogen rod - for code work it needs to be kept in a rod-oven once removed from the sealed package. It absorbs water otherwise and eliminates the Low-Hydrogen properties of the rod. Thousands are burned every day that are not dry - but that's not saying it's right. Rod holders extend the "open" time, but are not a replacement for a rod oven. 7018 has a (well deserved) reputation of being hard to start, and really hard to restrike - for an AC buzz-box - ONLY buy the 7018AC version which is specifically formulated for AC machines.
7014 is a shallow penetrating rod. Not a Lo-Hydrogen rod, it does not need to be kept in an oven. Easy running, it is a favourite of many welders but can be brittle and if not used by a skilled welder can result in a pretty but shallow weld. It is well suited to material under 3/8". After that, there are better alternatives.
As for undercutting - you have too much heat for the speed you are travelling. Undercutting is incomplete filling of cavity formed by the weld current. Watch the toes of the puddle and wait for the puddle to fill before moving away. Turning down the heat will reduce the size of the cavity, moving slower will allow more rod to fill the cavity. It's a blend of both.
You said you're making forks - I assume you have 3/4" or thicker material. In this case, you would need to bevel the material and make multiple passes, tieing the pieces together with the first, then filling in the bevel with either stringers or a weave, with proper cleaning between passes. I'd start with 6010 or 6011 then move to 7018 for the fill and cap myself, but you could do the whole thing with any of them. Just make sure you clean well between passes, and watch to ensure you have good tie in to the parent material on each pass.
7018 is a Lo-Hydrogen rod that is a medium to deep penetrating rod (Not low penetrating as stated earlier). Probably one of the highest volume rods of all. As a Lo-Hydrogen rod - for code work it needs to be kept in a rod-oven once removed from the sealed package. It absorbs water otherwise and eliminates the Low-Hydrogen properties of the rod. Thousands are burned every day that are not dry - but that's not saying it's right. Rod holders extend the "open" time, but are not a replacement for a rod oven. 7018 has a (well deserved) reputation of being hard to start, and really hard to restrike - for an AC buzz-box - ONLY buy the 7018AC version which is specifically formulated for AC machines.
7014 is a shallow penetrating rod. Not a Lo-Hydrogen rod, it does not need to be kept in an oven. Easy running, it is a favourite of many welders but can be brittle and if not used by a skilled welder can result in a pretty but shallow weld. It is well suited to material under 3/8". After that, there are better alternatives.
As for undercutting - you have too much heat for the speed you are travelling. Undercutting is incomplete filling of cavity formed by the weld current. Watch the toes of the puddle and wait for the puddle to fill before moving away. Turning down the heat will reduce the size of the cavity, moving slower will allow more rod to fill the cavity. It's a blend of both.
You said you're making forks - I assume you have 3/4" or thicker material. In this case, you would need to bevel the material and make multiple passes, tieing the pieces together with the first, then filling in the bevel with either stringers or a weave, with proper cleaning between passes. I'd start with 6010 or 6011 then move to 7018 for the fill and cap myself, but you could do the whole thing with any of them. Just make sure you clean well between passes, and watch to ensure you have good tie in to the parent material on each pass.
