[tommy b]

I have a Millermatic 135 with an M10 gun and I’ve got some questions as to wire feed speed.

Following Jody’s videos on basic tips and tricks, I’ve set the spool drag and feed roller pressure, using a welding glove to not quite be able to stop the wire from feeding.

My problem is this:

The chart inside my machine says that for welding 1/8” thick steel using C25 gas and .030” wire, the feed rate should be set at 60 to get 250 inches/minute. I measured the wire speeds for all settings from 10 to 100. Following this table it says that for a wire speed of 250 in/min I should set the dial at about 35. 35 is a long way from 60. I used a new .030” tip in the gun and I blew out the liner with compressed air. What could be causing this difference? Thanks for any help.

Tom

[LtBadd]

I don't have an answer for that, but if you make a weld with both settings that should tell you which is right. Hard to imagine their chart is that far off.

[tommy b]

That's what I was thinking. I'm wondering if there could be a problem with the liner. The machine is 12 years old but I probably ran only about 10 or 15 pounds of wire through it. Miller says that liner #194010 is for .023/.025 wire while liner #194011 is for .030/035 wire. Most of my welding up to recently has been with .023 wire. My local welding supply house says that I can run .023 wire through an .030 liner. I don't think that I could run .030 wire through an .023 liner. How can I tell what size liner is in my machine? Maybe the end of the liner is boogered up and dragging on the wire. Or maybe the liner is gunked up inside. I suppose I can just replace the liner. It's only about $25 to do so but I hate throwing money at a problem without knowing for sure what the problem is. (engineer's mentality) I guess I'll wait for some more input from the forum. Thanks, LtBadd, for your response.

Tom

[MinnesotaDave]

Are you saying it doesn't weld correctly by the door chart?

Or are you saying the numbers don't match so it's bothering you?

[tommy b]

The numbers don't match and I want to know why.

Tom

[tommy b]

I should say that the numbers aren't even close. If the were off by just a little bit, I could accept that. But why such a large difference? I'm pretty much a newbie at MIG welding and I'd like to know that my machine is operating properly before I start trying to change my procedures to get good welds.

Tom

[MinnesotaDave]

Not all machines feed the way you need for counting seconds and measuring wire.

If it welds properly by the door chart, use it.

In my experience with miller machines, the door chart has always been close enough to weld with - minor fine tuning from there.

[tommy b]

Dave,

Thanks for the input. Every bit of information helps.

Tom

[PeteM]

In a constant voltage system the current will adjust or vary based on thee wire feed speed, so if the wire is feeding at the right speed regardless of where the knob is, it should weld correctly.