mig and flux core tips and techniques, equipment, filler metal
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Merkava_4
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    Wed Apr 12, 2023 10:06 pm

Do I adjust the pressure while squeezing the trigger and having the wire feeding out?

What pressure setting?

Material --- 1/8" mild steel
Wire diameter --- .030"
Wire Type --- ER70S-6 Hobart
Gas Type --- 75/25
Input Voltage --- 240V
Machine --- Miller Multimatic 220 with stock pressure gauges
cj737
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    Thu Sep 29, 2016 8:59 am

For MIG, the gas only flows while holding the trigger. I use 35 CFH normally for MIG. Your mileage may vary…
Merkava_4
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    Wed Apr 12, 2023 10:06 pm

Hi cj737

I know that gas only flows while squeezing the trigger, but I wasn't sure if I should be setting the gauge while squeezing the trigger.

I think what is happening here is I'm confusing a flow meter for a pressure gauge. A pressure gauge is what I have. A flowmeter is the little ball that's floating inside the flow tube on the flowmeter. That little ball won't float unless the gas is flowing. A flowmeter is what they had in welding school for their TIG machines. 25 CFH at 100% Argon is what the setting was if I'm not mistaken.
Jack Ryan
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    Wed Mar 24, 2021 10:20 pm
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Merkava_4 wrote: Sat May 06, 2023 8:00 pm Hi cj737

I know that gas only flows while squeezing the trigger, but I wasn't sure if I should be setting the gauge while squeezing the trigger.

I think what is happening here is I'm confusing a flow meter for a pressure gauge. A pressure gauge is what I have. A flowmeter is the little ball that's floating inside the flow tube on the flowmeter. That little ball won't float unless the gas is flowing. A flowmeter is what they had in welding school for their TIG machines. 25 CFH at 100% Argon is what the setting was if I'm not mistaken.
What you have is probably a flow gauge. It will be calibrated in CFH (flow) not PSI (pressure). It is pretty much the same as a pressure gauge except it has a small orifice to limit the flow and it is calibrated for flow.

A flow gauge will show a high flow when there is no flow (trigger off) so you have to pull the trigger to set the flow. Many machines have a flow test function that turns the gas on but not the power or wire feed. If not, just cut off the excess wire after setting and watch watch you touch the wire too (it's live).

A flow meter (with the ball) also has to be set with the gas on but when the gas is off, the meter shows zero flow.

(25 CFH is pretty high for TIG)

Jack
Merkava_4
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Jack Ryan wrote: Sat May 06, 2023 9:07 pm What you have is probably a flow gauge. It will be calibrated in CFH (flow) not PSI (pressure). It is pretty much the same as a pressure gauge except it has a small orifice to limit the flow and it is calibrated for flow.

A flow gauge will show a high flow when there is no flow (trigger off) so you have to pull the trigger to set the flow. Many machines have a flow test function that turns the gas on but not the power or wire feed. If not, just cut off the excess wire after setting and watch watch you touch the wire too (it's live).

A flow meter (with the ball) also has to be set with the gas on but when the gas is off, the meter shows zero flow.

(25 CFH is pretty high for TIG)

Jack
Hey thanks Jack!

Tonight I set the flow to 20 CFH and everything went fine.

Ran out of wire. I guess the little sample spool that comes with the machine is not very much wire.
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