Metal Core

[HT2-4956]

I'm curious as to why my shop uses tri-mix with 2% oxygen. It gets EXTREMELY hot (I know welding is hot). I need to seek an answer to that question.

HT, what's your take on the matter.


Jim

Jim,

I'm thinking it might be a case of your company having been mislead by your welding supplier into thinking you need a more expensive shielding gas product than what you really do. If I'm not mistaken you mentioned in another thread that you were using ESAB Coreweld C6. According to ESAB's product data sheet the recommended shielding gas is either 75/25 or 90/10 (Ar/CO2).

It might be a good idea to print what's at this links off and pass it up the food chain where you work. Who knows, there might be an attaboy in it for you for saving the company some money.

http://www.esabna.com/us/en/products...Code=268&tab=2

One thing to be cautious of though is to make sure a change in shielding gas won't effect your WPQ (welder procedure qualification). I can for see some body maybe raising the concern that it would be an essential variable that would require recertifying it. If I were in your position I think I'd recommend to my supervisor that we at least got a bottle of 90/10 and do some test welding with it.

As to running metal core just being plain old hot I can certainly sympathize. I've got to find a different style welding cap that will keep both my ears covered because right now the skin on the backs of both of them are peeling off. More than once I've had the 400 amp Bernard guns we use so hot you don't even want to hold on to it by the very back of the handle (and you don't even want to think about touching the goose neck). Even with holding 5/8 to an inch stick out I've had the end of the nozzle glowing red at times and some of it smoke off. Running with 28 volts and around 300 amps all day is definetly not for the timid.

[HT2-4956]

I like that, I'm going to use that one.


Jim

Along those lines......

If some one ever points out a porosity hole in one of your welds the line of BS goes..."well to the untrained eye that may look like porosity but to those of us that really know what we're doing it's just a pre-placed stop crack hole".

When welding on bucket lips if any one pointed out any spatter to me they'd probably hear something along the lines of it not being spatter just additional "wear protection beans".

[welditforyou]

HT,
I'm going to print that document and submit it up the chain with that very thought of saving the company money. I will either get the attaboy or a pink slip (smile with a beer).

The addition of the oxy makes it burn hotter as it does with anything. (cotton fabric typically doesn't burn, it smolders. Now add oxy and it will go up in flames.)
We'll see what the company has to say.
Thanks.


Jim

[shovelon]

Dam Terry, you're doing some really nice work at your place. What are those rolled cylinders of expanded metal for?

Those are arena groomers. They get dragged behind a tractor.

[shovelon]

Terry what's up with all that steel...Last time i was there shop was full of 1" aluminum

Last year was painfully slow. The alum is coming back in and I hope it keeps coming.

[shovelon]

@ shovelon - are you fabricating a time machine or a Telsa human transporter? Very cool work Terry. As a related aside, WHY did you select metal core to weld the the assemblies? Totally asking, new to metal core. BTW, the welds look metronomic and robotic. Awesome!

I chose metalloy vantage cored wire to fill gaps, and keep the spatter to a minimum. It works pretty good for that. Goes into spray really fast. Those welds on the sheet was with C10 gas. The dome was with c25. For the screens I just use 70s-6.

[CEP]

OK, lets teach an old dog a new trick! One of the members here was gracious enough to ship me a roll of Hobart Fabcor CVN .045” Metal Core wire. Going to try my luck first thing in the morning! I was surprised to see my Lincoln V350-Pro has a place in the menu for Metal Core.

[wannab1]

At what point do hobby weldors get to use the excuses: "pre-placed stop crack hole", "wear protection beans", or the 'evil spirit release fissure?

[Tat2dHandz]

We use MCAW at my workplace, .045 but we're told to use it only on 3/8" thickness and up, some exceptions are made for 1/4" depending on the welder/fitter. On stuff thinner than 3/8" we are using .045 hard wire. We use 75/25 for both wires, which in my opinion could be changed. I would prefer to use 90/10 when using the metal core wire but because it costs more I'm guessing, the owner won't get it.

[CEP]

We use 75/25 for both wires

All I have is C-25 gas.

[HT2-4956]

At what point do hobby weldors get to use the excuses: "pre-placed stop crack hole", "wear protection beans", or the 'evil spirit release fissure?

You don't.

[HT2-4956]

All I have is C-25 gas.

I'm guessing it will run OK with C25 (especially in short circuit mode).

http://www.hobartbrothers.com/upload...FabCOR_CVN.pdf

[HT2-4956]

Passed my D1.1, 2G, 1" plate, full pen groove with a backing bar using .052 FabCor 86R today. The only surface that didn't have the mill scale on it was the bevel on the upper plate.

[shovelon]

Passed my D1.1, 2G, 1" plate, full pen groove with a backing bar using .052 FabCor 86R today. The only surface that didn't have the mill scale on it was the bevel on the upper plate.

Excellent!

Did the scale play with your head?

[CEP]

This Hobart Metal Core wire is slick!
I started out with the V350-Pro set on .045” Metal Core. Then switched it to CV Mig standard. I think I like that best. Played around with different settings on fillet welds.

[CEP]

Then I etched the welds to see what they looked like. 10 more amps makes a difference in the penetration.

[CEP]

Played with some V-groove welds. Need to play around with different land and gaps.

[HT2-4956]

CEP,

I don't believe you'll be able to spray in an open root pass. You'll need to get it turned down in to the short circuit transfer range.

I was using an 1/8 root opening and 1/16 land.

I pulled the puddle when I put the roots in (both horizontal and vertical down). I switched to pushing the puddle when I did the fills and caps in spray mode.

[Dan]

CEP,

I understand you're running C25. At those voltages was the wire trying to give you spray arc like characteristics or was it more of a high energy short circuit/globular transfer? If its the higher energy short arc/globular, I am wondering if an increase in the inductance (more arc on time) might no have helped improve puddle wet out.

[Silicon-based]

The pulse modes are designed for 90/10 gas. I don't think you will get the best results with 75/25. If you can score a tank of 90/10 (or 92/8 or 95/5) you will gain a whole new appreciation of your V350 Pro.

John

[soutthpaw]

When I get a tank of CO2, I plant to do some experimenting with my mixer on different %ages.

[CEP]

CEP,

I understand you're running C25. At those voltages was the wire trying to give you spray arc like characteristics or was it more of a high energy short circuit/globular transfer? If its the higher energy short arc/globular, I am wondering if an increase in the inductance (more arc on time) might no have helped improve puddle wet out.

Dan I'm not sure I would know the difference. With the V350-Pro set on Metal Core .045” I kept dropping the wave control to get the puddle to wet out. Funny the volts would not read on the display panel. I didn't like the results being on Metal Core .045”, that's when I switched the V350-Pro to Standard CV Mig. But like Silicon-based is saying with out C-10 it may not work very well.

When I switched to Standard CV Mig I could get the puddle to wet out by uping the voltage. But it just hit me when reading your post I forgot all about adjusting the pinch! The sound of the weld on Standard CV Mig made me think it wanted to go into spray. Kind of a neat sound! Hopefully I can get to town this morning to pick up the engine to my SA-200, if so I'll go by the welding supply and see if they have a bottle of C-10.

This is fun, you never see this kind of welding on a construction site!

[CEP]

Picked up a bottle of C-10 the other day. Played with it some yesterday morning.
I really like this metal core! Still think I like the V350-Pro set on Standard CV Mig tho.

[CEP]

Two more pictures.

[killdozerd11]

Looks good CEP