[cegasica]

Hi
Im taking welding classes. I'm from south Texas.
while taking my 3G Open Root bend Test, It fail. the cupons broke both on the root side and the cap side
It was a long crack parallen to the groove ( sorry forgot to take pictures) acoording to my teacher was lack of fusion
I have not have too much practice so I not sure what was wrong. these are my settings
Runnin on a Miller "Shop mate 300 DX"
3/8" 6" X 6" plate
30 deg bevel (60 deg groove)
1/8" land 1/8" gap
Root pass with 6010 5P+ at 72 amps
hot pass with 7018 excalibur at 105 amps sligth weeb
Fill 7018 exc. at 95 amps
cap 7018 exc. at 105 amps
What was wrong and what do I need to do better?
any help will be greatly apreciated. Thanks

[Poland308]

It can take a while to get a concistant root with 6010. So don't get discouraged. But if your running 1/8 inch 7018 then those amps look a little low. Try running about 10 amps more. Turning it up by about 3-5 amps at a time to find what you are comfortable running at. Some people will run even up around 130-140 with the 1/8 inch rod.

[cegasica]

It can take a while to get a concistant root with 6010. So don't get discouraged. But if your running 1/8 inch 7018 then those amps look a little low. Try running about 10 amps more. Turning it up by about 3-5 amps at a time to find what you are comfortable running at. Some people will run even up around 130-140 with the 1/8 inch rod.

Thanks "Polan308"
At this amps (105 amps) on the hot pass, at the end of the groove it tends to melt big time the plate and I know is the heat goes up, so, if I run it at 110 or 115, wont it be worst? or what its the tecnic?

[Poland308]

I didn't catch yet what size rod are you running?

[MinnesotaDave]

It can take a while to get a concistant root with 6010. So don't get discouraged. But if your running 1/8 inch 7018 then those amps look a little low. Try running about 10 amps more. Turning it up by about 3-5 amps at a time to find what you are comfortable running at. Some people will run even up around 130-140 with the 1/8 inch rod.

Thanks "Polan308"
At this amps (105 amps) on the hot pass, at the end of the groove it tends to melt big time the plate and I know is the heat goes up, so, if I run it at 110 or 115, wont it be worst? or what its the tecnic?

As the amps go up, so does travel speed.

But I'd be concerned about the root pass too.

Since it split both ways, overall technique is in question.

You may not have heated the edges (toes) enough for proper fusion.

[cegasica]

I didn't catch yet what size rod are you running?

1/8" on both 6010 and 7018

[cegasica]

It can take a while to get a concistant root with 6010. So don't get discouraged. But if your running 1/8 inch 7018 then those amps look a little low. Try running about 10 amps more. Turning it up by about 3-5 amps at a time to find what you are comfortable running at. Some people will run even up around 130-140 with the 1/8 inch rod.

Thanks "Polan308"
At this amps (105 amps) on the hot pass, at the end of the groove it tends to melt big time the plate and I know is the heat goes up, so, if I run it at 110 or 115, wont it be worst? or what its the tecnic?

As the amps go up, so does travel speed.

But I'd be concerned about the root pass too.

Since it split both ways, overall technique is in question.
You may not have heated the edges (toes) enough for proper fusion.

I think this is what I'm missing heating the edges. I'll try this next Thursday.

[MinnesotaDave]

I think this is what I'm missing heating the edges. I'll try this next Thursday.

A little pause at the toes on each side generally fixes it.

[Otto Nobedder]

I think this is what I'm missing heating the edges. I'll try this next Thursday.

A little pause at the toes on each side generally fixes it.

Yep, that is where the work is done. Time on the sides provides penetration and fills the toes avoiding undercut. Time across the middle only builds crown. Spend your time and attention on the sides.

Steve S

[kevin3818]

i know this is a late response but here is what i have to say about it. The key to a good root pass, which from my hypothesis is your problem is having good fusion and penetrating enough. Your amps for what you were running your 6010 at was low too. so you want to turn that up to get good penetration and make sure you pause when you manipulate into the plate to get a good fusion. because if you don't the metal wont be completely joined causing gaps and undercut, resulting in potential cracking. which in turn it can crack and split apart when you bend it.