How to spray with 350P?

[Arc weld]

To use pulse mode in spray transfer you need 90/10 (ish) blend of gas, personally I usually use an 88/12 blend. DO NOT use 80/20 or 82/18 as stated above by Everlast and Airgas, pretty much all you need to know there...:thumbdown: For Spray transfer you need a higher percentage of argon and typically higher voltage then you would normally use in short circuit. Voltage is to electricity as pressure is to water, the voltage is what is pushing the puddle down into the base metal.

If you have only been using short circuit transfer with your 350P then honestly you have seriously overpaid and are not even beginning to use the full potential of the machine. Once you go pulse you'll never go back, seriously! Penetration almost like stick, smooth spatter free welds, what more could you ask for!

The "MIG" mode chart is telling you to use spray transfer for the thicker materials because spray has more penetration. As is often the case with unskilled weldors, they can lay down a "pretty" bead that is doing nothing more than sticking to the surface of the base metal and can easily be broken off. It's actually quite shocking to them when you show how poor their "weld" is when you hit it with a hammer and peel off their bead.

As a new member you're not off to a very good start. Spray transfer depends on more than volts and shielding gas mix. Wire size and amps play a role too. Sometimes globular transfer can be confused with spray. Here's a good article on MIG transfer modes and by golly 80/20 can spray at high amps.

Understanding transfer modes for GMAW - TheFabricator.com

 

[Mysfyt]

Last time I did spray transfer was back in the late 90's. I thought they had a couple percent oxygen in the mix. Whatever happened with that? Not an expert here, just asking.

 

[Shield Arc]

I wasn't all that impressed with spray. The metal has to be way to clean for me!:thumbdown:
I really liked metal core.

 

[yomax4]

As long as you have Pulse, You don't need Spray. If you really want to try spray, Turn off the pulse, Set volts at about 23 and start a bead. Keep turning your wire speed down until you just get a hiss and a red hot flat no spatter weld. Argon 90 CO2 10 is the min. Like stated above, If you only have 75/25 you can still get the idea by turning up the volts while welding until you get the hiss or turning down the wire til you get the hiss. If Miller says 98/2 ( Argon/ Co2 ) that would be more of a Pulse Stainless mix. Lastly, The newer Digital High Def equipment from Europe can weld with Straight CO2 with No spatter and flat Spray / Pulse looking welds. They only use CO2 in Europe and they are wayyy ahead of the USA in the welding world. ( See Fronius, Lorch or OTC from Japan ) I like the Miller 350P machine ok but it's analog where the Lincoln equivalent is Digital. Not HD but close. Have fun with all the transfers and you will find uses for most of them.. It's all awesome.

 

[BukitCase]

Actually Miller's calculator recommends 98 Ar, 2% O2 -

MIG Solid-Core Welding Calculator - MillerWelds

Choose steel, 1/4" for an example... Steve

 

[Mark @ Everlast]

Yeah, Millers charts are known for being wrong...or lets just say what they want you to do so their equipment shines. Not necessarily what can be done, or is done.

 

[TORQUIN]

Thanks for all the opinions and info. I'm going to have to get a different mix to try this stuff out because when I tried spray with my 75/25 mix I got a lot of spatter. I do not know if this was because of the gas mix, but it is my prime suspect.
The only other gas I have right now is 100 Arg on the TIG.

Thanks,
Chris

 

[Mark @ Everlast]

You can get a simple flow mixer and create your own.

 

[plastikosmd]

What are you trying to spray that pulse won't do? Love my 350p, I pretty much only pulse now