Mig wire and silicon islands

Date 10-30-2003 23:28

Chances are your pulling it in your weld probably from your base metal.
Make sure it's properly cleaned. I would have to say your probably using hard wire and perhaps your steel might have a black coating on it to help prevent rusting. That could be the source.

I presume your welding tubes.

By jwright650 (*****)

Date 10-31-2003 12:03

We tried some Metalcore wire a while back and found that if the steel isn't perfectly clean we had loads of silicon to chip off, however if we ground every part of the joint down to absolute clean material it wasn't nearly as bad. All that extra effort it took to prepare the joints for welding wasn't worth any of the other advantages it had over fluxcore we presently use. My guess is that your base metal isn't clean enough for the type of wire/gas you are using. Gotta get that stuff very clean to avoid those silicon islands on top of the weld bead. Check to see if you notice a difference when you clean really good and when you don't. I bet you'll find lack of preparation rather than the wire is the source. Fluxcore/CO2 isn't as funny about how clean the joint is and is more forgiving. It digs and cleans better than solid wire. You'll still have to chip slag, but it isn't as tough to get off as the silicon.
John Wright

By pino

Date 10-31-2003 12:06

I should have explained that it is always imperative to me anyways to clean the carbon off at all weld joints so there is nothing but silver metal to join togeather.

By jwright650 (*****)

Date 10-31-2003 12:09

Good Morning Pino,
What type of wire/gas are you using?
John Wright

By pino

Date 10-31-2003 15:36

Good morning john the gas is a 92% Argon 8% CO2 and the wire is AWS ER 70S-6 just a typical carbon hard wire.

By jwright650 (*****)

Date 10-31-2003 16:17

pino,
Sounds like you have a very common set up.
Seems like it may be a wire quality issue if you are confident that the joints are being cleaned well; operator and machine variables are consistant; and it only happens from one roll of wire to the next.
John Wright

By ssbn727 (*****)

Date 10-31-2003 18:05

Hi Pino!

I would have to agree with JW on the possible wire quality issue...
I would ony suggest to replace that spool with one previously used on another station that you know is'nt producing the same amounts of excessive silicon that you mentioned. Observe how the operator's technique could also effect this. This wil show if indeed this spool is defective or if the welding technique is the source of the problem. TIG6al-4v made a good point about how the technique could also be the cause. Finally, I have a question for you; What grade of carbon steel is the base material?

Respectfully.

SSBN727 Run Silent... Run Deep!!!

By pino

Date 10-31-2003 18:57

Here in Canada we call it W44 I believe it is A36 under D1.1.

By ssbn727 (*****)

Date 10-31-2003 19:42

Hi Pino!

Well if your in Canada then, Ed Craig is someone that you might be familiar with am I correct?
Check out his website in case you have not...
http://www.weldreality.com
I do not know if he still takes questions via e-mail but, he did the last time I checked. He's a GMAW/FCAW/MCAW process expert that is in my opinion FWIW, is invaluable for anyone involved with the above mentioned processes...
Oh yeah I almost forgot, Is the silicon content of the W44 the same as in A36 as far as percentages go and, what brand of wire are you using? What thickness/structural shape is the material?
Silicon is used in MIG welding wire primariliy as deoxidizing agent along with other elements as you already know and yet, with Flux core wire, you do'nt have all of these issues to address as JW has mentioned before so, if I were you, I'd look into flux core as an alternative to your current process application...

Respectfully,

SSBN727 Run Silent... Run Deep!!!