Spray mode

You can't make any money unless you are in spray once you are dealing with material over quarter inch thick on the flat and horizontal. Globular transfer is messy and short circuit is as slow as molasses. You need 20 percent or less carbon dioxide in order for your machine to maintain spray. You cannot get a proper spray mode with 75/25. We run something around 92/8 and yes you can turn it down to do short circuit transfer. We do it all the time for small handrail. What diameter and number of wire are you running? Randy

-- Stupendous Man, Defender of Freedom, Advocate of Liberty

Thanks. I mostly TIG when welding at work, the MIG is my home toy for fab work. I won't be doing any production work with it, or much work with heavy plate, so it won't pay to buy another cyl for a third gas, so i guess i wont try it. Slow is fine when you are having fun I'm running a Lincoln 215 with .035 currently, it's maiden job was this frame, fully boxed with sections from a matching frame for a low-budget rock crawler

Usually at work i make stuff like these Lotus oil caps or work on building the F2 car

Speaking as someone who only gets to weld while learning at a technical college at the moment...

Spray is interesting to see, if you have only ever known dip.

I think even at the best of times you only break into spray at higher currents and voltages than you are ever going to draw the power for off a domestic supply (and that's from a European perspective where everything domestic is 240V). So you may have to find someone who has an industrial premises.

You can use a gas which will support spray in dip. But you can't force dip at high wire-feed-speed and voltage when the gas supports spray (?).

Richard Smith

Most of my welding is for tooling and machinery used in blacksmithing. Spray is pretty useful when your material is usually 1/2" and thicker.

I prefer 85/15 or so, but when I moved here, the welding shop couldn't figure out what I wanted, so I ended up with 75/25 (I'm still working on the same bottle). I can spray with 75/25 at about 30V. I'm using a 250A mig with .035 wire.

Caveat: I'm self taught and do this on weekends.

Steve

Stupendous Man wrote:

Unless you have a very large machine there is no way you will get anywhere near spray until you get to 20 percent or less carbon dioxide. Some machines that can customise current characteristics such as a Powerwave can sorta do spray in these situations of over 20 percent CO2. You need at least a 300 amp machine and run .045 wire to commercially benefit from the speed and freedom from spatter. I have a 250 amp machine at home with 20 percent CO2 and with .035 I get spray but the machine is maxed out. Randy

I prefer 85/15 or so, but when I moved here, the welding shop couldn't figure out what I wanted, so I ended up with 75/25 (I'm still working on the same bottle). I can spray with 75/25 at about 30V. I'm using a 250A mig with .035 wire.

Caveat: I'm self taught and do this on weekends.

Steve

Stupendous Man wrote:

Aren't you supposed to use a hammer? lol I don't often fab anything over 3/8, but intend to start experimenting with some heavy aluminum plate using my ready-welder as a spoolgun after i finish this Jeep..

Absolutely. Globular with straight CO2 is messy, my new bottle of 75/25 will arrive today. My previous machine is an early 100A mini-MIG I bought over 20 years ago. It served me well but had serious limitations. I love trying new techniques and taking on challenging projects

Randy, You are one of the people on this group whose messages I always read. I have learned a lot from you. And have even gotten to the point where holding an angle grinder off to the side seems natural. However I differ with you on spray mode. Not on straight wire, but on dual shield. I got some Rockmount Polaris Maximum Shield at Boeing Surplus. It is a dual shield alloy made to use with CO2. The data sheet has the following:

Volts AMPS Gas Flow Stick-Out Short Arc 20-26 100-250 35-45 3/4 inch

Spray Arc 28-32 150 40-50 3/4 inch

It also says a mixture of 75-25 will improve characteristics in out of position work. When using Argon/CO2 mix voltage should be reduced 1 to

1 1/2 volts.

I have a little Lincoln 175 and it will work in spray mode with this wire. The wire I have is .035 and works well on 1/4 inch material in spray mode.

I have some ESAB dual shield, but have not tried it.

Dan

Anytime you add flux to the mix you change the rules. For hard wire Randy is right (except for really high powered machines which can throw 35 volts at 250+ amps). Flux core is often spray even at low voltages (depends on the wire).

Hi, I'm new to the group but am finding it all an interesting read. I'm a little confused about the Argon CO2 mix issue. If adding CO2 to the mix increases arc temperature and penetration, would it then encourage spray transfer with a higher CO2 content, not a lower percentage as suggested. Wondering? Rod Day

Spray transfer happens around 25 volts and higher depending on the nature of the ionized gas in the arc. At work we are running around 27 volts and over

400 inches per minute wire feed rate. Spray transfer is not a highly penetrative arc but is very smooth with no spatter when set correctly. The objective is to maximise deposition rate. ( flat and horizontal only) In fact, one common weld fault found when running spray is lack of fusion at the edges of the bead. Spray transfer Is not that great when you are running beads for hour after hour after hour. At least one 20 kg roll of wire is gone per shift, sometimes more. You might even have a machine with shielding gas on a manifold and a 500 pound drum of wire. You look forward to your coffee breaks:'))) Randy