If it is welding it should be getting the voltage/amperage required. I think I read that it can be +-10% 120V/240V I don't remember for sure. Are you using the machine on 120v or 240v? If you are on 120v then you are near the max amperage for stick welding. When I use my Maxstar on 120v it seems to weld a little colder than the listed amperage on the knob but I haven't had trouble with pinholes. Be sure to check the electrodes you are using for cracks/missing flux, I have had times when I didn't check and got porosity because of that.
What size electrodes are you using? I assume 3/32" from the amperage but I have seen guys try to weld really cold and have trouble..

 

Crap steel ? It happens. Not too often but likely more in the years to come.
Think of steel as beer. The recipe has to be right. ESPECIALLY when it comes to tool steel.

 

No grease straight from steel supplier.

I'm not sure if you are saying that it's new material, therefore it's "clean" or if you mean you have degreased it after you bought it. A lot of the steel I get from the supplier has a protective layer of oil on it. It's filthy unless I wipe it down and degrease it even though it's new material.

 

Everything is ground down shiny, and wiped with acetone. The reason I acetoned it is because of the grease or whatever was on it. Yes it is 3/32 electrodes, and also I said I welded on worse steel than this with much better results. It just doesn't make sense that these pinholes and inclusions are everywhere. I tried an 1/8" at 95, thats not what I would normally be welding 1/8" at but since it was 1/8" wall I didn't want to blow through.

 

Arc blow? Just a random idea. Have pictures of the welds? Pictures of other welds made with the same electrodes/machine?

 

Good possibility. Check all the wires and move the ground around.


Weld on!

 

I'd heat the weld zones up with a torch.

 

Changing rod angle/ welding direction/ ground location..Lots of things can help with arc blow. One thing I have noticed with the Maxstar is it needs a good ground, when I don't have a good ground the rods stick really bad. Need to clamp to a clean spot, leaning a piece of steel onto the workpiece may not give a good ground and could be part of the problem. If you can't find another way just be sure the steel is ground clean where it is touching the grounded steel (also ground clean). Add some weight to the steel so that there is less chance of it moving and causing a bad ground.

 

Oh man I completely fudged on cleaning the ground clamp area. Doh.

 

Arc blow on a tube frame weld cart? I can't see it.
Where is your porosity developing? Is it in your entire bead? Just at the start of your bead? Or at the end of your bead?

 

I'm suspecting that too long of arc length and or improper rod angle may be your issue resulting in loss of shielding which will lead to porosity issues.

 

Are your rods wet, moist?


I have a maxstar 200 DX and weld carbon pipe all day. No real cleaning and just a brass ground clamp, where ever I can attach it (40' away on a pipe hanger, structural steel) nothing fancy.

 

Those slag inclusions are easy to get with 6013. What I have found works best:

Pause after the arc is struck long enough to form a puddle connecting both pieces, then proceed. Maintain a short arc gap (smaller than rod diameter). Lightly dragging the coating is OK.

7018s do not usually have that issue but again too long an arc gap may be the cause.

Arc blow is usually worst in inside corners, such as boxes or frames made from angle iron. If you have to weld inside corners with DC, start right in the corner and move outward; avoid welding into the corner.

John

 

Could always tack a piece of flat steel near to the welding area and clamp that.