Penetration

[Planet X]

Here is yet one more question for the welding enthusiast;
" Select the best method to increase Mig or flux cored weld penetration"
[a] increase voltage
[b] increase current
[c] reduce travel speed
[d] use larger wire.

These 'questions' are not tests- when you 'know' the answers, weld salesmanship has much less influence over your "weld decision making process"

If you don't know the answers, take a look around your personal welding area- and ask yourself, why did you buy that wire? why are you using that mix?, and why are you using those settings? why did you buy that powersource?

If you can approach a welding application having a good idea what you need to do to produce sound welds, you will be better prepared when you go down to the welding store to get 'supplies' and will not be dependent on what the guy behind the counter is telling/selling you-unless he confirms what you already knew...

[JEFF75]

my answer would be a mix of b and c. because if you are not getting the proper penetration and your travel speed is good then you would need to increase current.or if your current is good and you are not getting good penetration then you could slow down travel speed.by the way i like the questions you post gets me thinking...

[Zrexxer]

Penetration is increased with the MIG process mainly by a) increasing voltage.

Increasing current (wire speed) or slowing travel causes more filler metal to build up on the surface, but not much more penetration without a corresponding voltage increase.

[Planet X]

Something to think about here is this curious factoid of mig ;
If you increase your electrode stickout-current drops, If you decrease your electrode stickout-voltage increases.

Hmm, now sometimes while welding thin sheetmetal like around 18-16 gauge I will make a long stickout on purpose to minimize weld drop through or burn through.;)

[JEFF75]

see, learn somthing new everyday....

[Ryel]

OH! THAT kind of penetration...you had me going.

[Planet X]

Originally posted by JEFF75
see, learn somthing new everyday....

You were on the right track, it is current, but this is only text book sort've stuff, you would likely still have to adjust your parameters which of course may include voltage.

Voltage is more of an arc distance thing... Check over on the Chaski board Ken_m, left a pretty complete/complex explanation.

:cool:

[Franz]

You gous are WAY overthinkin a smiple function again.
Put the damn book on the shelf and go practice, you'll know when ther machine is set right.

[Planet X]

Originally posted by Franz
You gous are WAY overthinkin a smiple function again.
Put the damn book on the shelf and go practice, you'll know when ther machine is set right.

Franz, I agree the manual skills need to be practiced but I think there is room for the 'process' side of things too. As an example the trailer that I recently worked on had some mig welds on it that would never have come out of my 'garage', but they did come out of a place whose business is building trailers.
My thinking is that the person in charge of the welding dept. there had no idea that the welds should have been made with spray settings which would have saved time not to mention a stronger weld.

Reading through either ED Craigs website or books, he tells a story of a major auto-maker, that was having welding re-work problems. This was costing the company bank. Basically the Welding 'engineer' , refused to listen to the recommendation that Mr. Craig made (they paid him to consult), and continued using the specs from the 'engineer'. The auto-maker ended up moving the line down to Mexico-perhaps because with the labor savings they would be able to make up for the $$ they were wasting on welding re-work.
Hopefully if there is any justice in this world that engineer found himself unemployed along with everybody else because of his ignorance. But at his level he most likely escaped this scenario and wormed into some other high level function
:rolleyes:

The above may not really have much to do with the average hobbyist's, but I'll be damned if some welder in a third world country will know more than me... fortunate enough to live in an industrial country:cool:

[Franz]

X, the big problem is when people rely on the technical side, because they lack the personal experience to know when they are welding, rather than using a hot glue gun.
I've seen more postings over time relative to "the chart says" or if I switch to this gas than I can count, and the underlying factor in all those posts is the reality the guy simply doesn't know when he's welding rather than piling crap on top of steel.
Part of this is because every box store and drop shipper is selling machines to people who barely know how to turn them on, and part of it is because local suppliers selling gas only to these people either don't give a damn because of their limited profit from these customers, or flat out lack the IQ behind the counter to set these guys straight.
On the industrial side,problems are caused by "welding engineers" who couldn't weld to save their lives, and, as Craig says, salesmen pushing machines that aren't the right machine for bigger comissions. Factor in the campaign being pushed by Lincoln to eliminate weldOrs, and replace them with welding machine operators. That thinking has been sold to the MBA idiots currently directing manufacturing, to the detrement of product.
Around here, we say Kodak can train an ape to MIG in 2 hours, but they will never teach him to weld.
Old Farts, like me, who saw the arrival of MIG, and waited a few years to consider it anything beyond a new method for car body repair shops, are retiring or croaking, so the evolution of MIG is being lost to the new guys.
The trailer you mention is a pime example of the loss of skills in the world. The probability is the "welds" you site were made by a welding OPERATOR who was running a machine set to specs, witch in reality was a hot glue gun. There is a posting on the AWS board where a guy is trying to pass a MIG test on tubing for some manufacturer, where the machine is preset and locked down by the employer, and most people testing are burning thru.
It's in the nature of employers in manufacturing to continuously lower costs, and replace skilled labor with unskilled labor, and that is happening in welding. MBA thinking doesn't allow for different skill levels between employee units, but does allow consideration of differing machine capabilitys.
I've said for years the weld isn't in the machine, it's in the man behind the mask, and it holds as true today as it did 30 years ago.
For a guy running a small machine to think if he just buys the right wire/gas mix, and sets the machine at the proper numbers he's going to lay down a perfect weld is pure WRONG. I welded a running board at a friend's shop last week with his 120 volt Lincoln, because he had become totally frustrated, and had trouble with the machine maxed out. I looked at the situation, and had him clean the crud out of the nozzle, and replace the contact tip. The machine still SUCKED, so I looked at the incoming power, and determined the problem was insufficient incoming power to the machine. That's the difference experience makes.

[axehind]

Originally posted by Franz

It's in the nature of employers in manufacturing to continuously lower costs, and replace skilled labor with unskilled labor, and that is happening in welding. MBA thinking doesn't allow for different skill levels between employee units, but does allow consideration of differing machine capabilitys.


Is it me or do have it in for the MBA people? :D

axehind

[Franz]

Lets think about it, they spend a ton of money to get a piece of paper that says they are qualified to run a business.
Their basic premise is that employees will know their function, report to work promptly, and perform their task properly.
They have no idea of the difference between a lathe and a drill press, and only might be able to determine witch is witch if they carry a catalogue from their cube to the shop floor.
Naw, I don't have a problem with MBAs, it's just easier than typing Mind Blown A$$holes.

[axehind]

Originally posted by Franz
Lets think about it, they spend a ton of money to get a piece of paper that says they are qualified to run a business.
Their basic premise is that employees will know their function, report to work promptly, and perform their task properly.
They have no idea of the difference between a lathe and a drill press, and only might be able to determine witch is witch if they carry a catalogue from their cube to the shop floor.
Naw, I don't have a problem with MBAs, it's just easier than typing Mind Blown A$$holes.

Is this prejudice only for MBA's or does it expand to PhD's as well?
I'm sorry if I'm stiring things up. I always appreciated the way you put things Franz.

axehind

[Franz]

I got nothing against Post Hole Diggers, like em a lot better than a shovel.
Or were you talking about the Doctors of Phylosophy who actually have a legitimate degree after writing and defending a thesis, or all the phoney bastards who bought paper mailorder.
I'm acquainted with a couple real PHds who are brilliant, in their VERY narrow field, and smart enough to know where the edges of their field are. They ain't allowed near power or hand tools!
I also know a bunch of a$$holes with the FAKE EdD bastards who suck gigantic money out of society and screw up kids.
Degrees belong on thermometers and compass roses, not people.
A$$wipes who like being called Doctor need to be watched 24/7 with both eyes.

[arcdawg]

Franz, i really enjoyed your post on this subject, informative as ususal. you hit it right on about how some guy goes down to the local home depot and buys a lil mig and thinks that just cause hes college educated hes going to be welding like a pro in a hour !!
i see that on some of the boards out there, especially now with the inverter tig machines, just because its got a bunch of bells and whistlles doesnt mean that its going to weld FOR you !!!
if people want to learn how to weld they should get some metal and some rods or wire and start WELDING !!

brian