[69lm69gp]

Dragncar,

After I read your comments I did some research. I found several other boards where the same comment as mine were made and others that recomend against using flux core wire but no explanation as to why where given. I then checked the weld parameter charts on Miller's website.

http://www.millerwelds.com/education...llermatic.html

I found that flux core wire requires less voltage than solid wire and the same thickness of materal. And that with all but one of Miller's welders welding 20 gauge sheet metal with flux core wire was not recomended as it appears that you can not set the voltage low enough. The chart supports your comment that flux core wire needs less heat to weld a given materal. However the materal being welded still needs the same amount of heat to get good penitration. Therefore flux core must generate more heat than solid wire at the same voltage setting.

So I was wrong in my earlier comment that flux core with requires more heat, it doesn't, but it does generate more heat and depending on your welder you may not be able to turn your welder down enough to prevent burn through.

[Dragncar]

69lm69gp,the reason a solid wire requires more current than a flux cored wire is that the solid wire is all metal and the flux cored wire is not all metal.My comment was not about the current to weld a given matterial,it was about the current needed for the dia wire.Flux core wire is well.... not solid so there is less in it to melt compaired to a solid core wire of the same dia.That is why solid core wire needs more heat.
You are talking about some chart,look its 20 gauge sheet metal.Penitration is not an issue for steel that thin.If the current setting on the welder is the same,it is the same heat with both wires OK.
You prevent burn through by using common sense and getting your finger off the trigger.There is simply no such thing as flux core burns through and gas shielded does not.When you weld in a long bead the heat builds up in the metal you are welding and it is more prone to burn through the longer you stay in it.What I am saying is get out of it,short3/8s long beads and cool it off as soon as you finger gets off the trigger.It is not hard.
Its a urban myth started by people who do not know how to weld very good.

[Pearlbluebird]

Originally Posted by Jim Doran

Not cheap, but I have the Lincoln SP135 Plus. Provides infinite voltage control. I typically use a 75% CO2 and 25% Argon mix of Gas. Provides very nice welds and will do up to a 1/4" in a single pass if needed. I've yet to try Aluminum wire feed as it is a PITA and requires typically a new gun. Depending on requirements, but if I had to do it over again, I'd think hard about a TIG setup, albeit at twice the price.

Jim your Lincoln Sp 135 Plus will not have what it takes to mig weld aluminum. You do need the spool gun attachment also. Straight Argon gas, or Helishield gas is recommended.The Helishield is mostly argon with a little helium mixed in to help promote cleaning.
As for mild steel welding, stick with the shielding gas. It is much easier for the novice hobbiest. Flux core has its uses but lets let the farmers keep most of it.
Dragncar I do see what you are saying but for someone who does not weld for a living. I believe it would be easier for them to learn with the hard wire and gas. I don't know of one body shop that would use flux core to put on quarters? Any body shop owners out there ?

[TinInjun]

Dragncar knows what he is talking about people. Listen to him and you may learn something. As he stated there is nothing wrong with using flux core wire, and you better use it if you weld outside if there is any kind of breeze. Body shops use solid core for one reason, COST!!! You can get more welding done cost wise using solid core and gas than using flux core.
You need a top of the line MIG to weld aluminum. It needs high amp rating. It takes more than double the amperage to weld two pieces of aluminum together than steel for the same thickness. Example(TIG) If I were to weld .040 steel I use the rule of 10 amps per every .010 of thickness. So 40 amps would be the total. The same thickness of aluminum I would use 100 amps. The difference between the two metals is their heat conductivity. Steel retains heat in a smaller area, whereas aluminum disipates it very fast. Welding stainless is a different setting also, but I won't go into that right now.
Bottom line is if you want to learn welding, a small 110 volt welder like a Lincoln Weld Pack 100 with flux core wire is the most cost effective way to go. You can weld just about anything you need to on a car with it. That includes body panels. Its the person using the gun that makes the weld, not the welder.

[BILTIT]

So 250 amps for 1/4 inch steel? I did not realize it would be that much. I assume MIG is abit less.

[Pearlbluebird]

Originally Posted by TinInjun

Dragncar knows what he is talking about people. Listen to him and you may learn something. As he stated there is nothing wrong with using flux core wire, and you better use it if you weld outside if there is any kind of breeze. Body shops use solid core for one reason, COST!!! You can get more welding done cost wise using solid core and gas than using flux core.
You need a top of the line MIG to weld aluminum. It needs high amp rating. It takes more than double the amperage to weld two pieces of aluminum together than steel for the same thickness. Example(TIG) If I were to weld .040 steel I use the rule of 10 amps per every .010 of thickness. So 40 amps would be the total. The same thickness of aluminum I would use 100 amps. The difference between the two metals is their heat conductivity. Steel retains heat in a smaller area, whereas aluminum disipates it very fast. Welding stainless is a different setting also, but I won't go into that right now.
Bottom line is if you want to learn welding, a small 110 volt welder like a Lincoln Weld Pack 100 with flux core wire is the most cost effective way to go. You can weld just about anything you need to on a car with it. That includes body panels. Its the person using the gun that makes the weld, not the welder.

TinInjun I'm not saying that Dragncar is wrong. My point is for the novice the hard wire and shielding gas is easier to learn and use. As for welding outside, shielding gas can blow away causing porosity. It does take a fair bit and of course use a wind break if needed. Myself I worked for years as a Welder, went back to school and worked for years as a welding inspector in various pressure vessel shops that were U and S stamp registered. I gave the welding tests to ticket welders. I could bury alot of people in theory but that would not solve nor prove anything.
As an example. I was working in a shipyard at the time where 90% of what they welded was 6011 and 7018. They were just starting to use mig with the innershield flux core wire.
The welders hated it. I made mention to use C02 as a shielding gas but use a different flux core wire. Of course another welding procedure had to written and approved for use. Today there still using this. Remember this is a ship yard it is a wind tunnel and they still use shielding gas. Every welding consumable does have a purpose. Dragncar sounds like he has alot of skill and knowledge and he's lucky he can save a few bucks if he wants to use the flux core wire. I still maintain for the novice it my be a few dollars more like you said but they won't be cursing since it is easier to use and will be able to stand back and say I did that.

[shawn e.]

I have the Lincoln Pro 135. I have no issues with it and as much as I use it I am glad I did not fork out the money for anything else.

[69lm69gp]

Originally Posted by Dragncar

69lm69gp,the reason a solid wire requires more current than a flux cored wire is that the solid wire is all metal and the flux cored wire is not all metal.My comment was not about the current to weld a given matterial,it was about the current needed for the dia wire.Flux core wire is well.... not solid so there is less in it to melt compaired to a solid core wire of the same dia.That is why solid core wire needs more heat.

I never said that this was incorrect.

Originally Posted by Dragncar

You are talking about some chart,.

Yes the weld parameter chart, you know the chart that on the inside of most welders that tell you what setting to use with whatever wire/gas/materal you are using (See attachment). BTW as I stated earlier all but one of Miller's welders do not recommend welding anything thiner that 18 gauge with flux core wire. But you can go as low a 24 guage with .024 solid wire (on some machines). Why is that?

[Dragncar]

All of this because I am trying to let some people know that flux core is OK if thats what you have.So many people say whatever you do"do not use flux core wire"I am simply trying to tell people that is not true,and it isnt.
Cost is a big factor in hard wire vs flux core.Flux core cost 3 times as much.
Most of the time I will use hard wire,I would rather use it.But I have a choice,I am a skilled welder and several welders and access to anything I want.
69lm69gp,I know what a weld parameter chart is.Have lots of them and welding books,some 1300 pages and principles and practices.Tons of info.Charts are basic parameters,but those change in the real world.There is no subsitute for actualy doing it,lots burning metal.Just by changing the length of lead on a welding machine changes everything.So it is up to the welder to find the sweet spot on the welder for what you are doing at that moment.
And the answer to your question is,because they do not make flux core in .023,.030 is as small as it gets.If thet did it would require less current than .023 solid.It might just be too difficult to manufacture it.

[69lm69gp]

No, all this because you pointed out that my statment was incorrect so I tried to find the real answer. Then you dismissed what I came up with as from "some chart". I never said it couldn't be done.

Now I asked the question "all but one of Miller's welders do not recommend welding anything thinner than 18 gauge with flux core wire. But you can go as low a 24 guage with .024 solid wire (on some machines). Why is that?"

Your answer was: "because they do not make flux core in .023" ??

The real answer is burn through. Yes with the right technique and skill you can keep burn through to a minimum I never said it couldn't be done. However for a person with little welding experance using .023 wire and gas is more forgiving. This is the experiance that Dan968 related in his post.

[TinInjun]

Originally Posted by BILTIT

So 250 amps for 1/4 inch steel? I did not realize it would be that much. I assume MIG is abit less.

That is the preference I use for welding sheet metal using a TIG machine. Plate steel is a different deal. Thinner sheet has a different heat conductivity than thick plate plate steel. You can use less amperage with the thick stuff as it retains more heat in a smaller area whereas thin sheet will spread the heat out faster so you have to use more amperage than you think you should. 1/4 steel I would be looking at 75 to 80 amps, then fine tune the adjustment when I start welding. Just remember that each type of metal welds differently be it sheet steel , plate steel, aluminum sheet and so on. It is up the the welder to make the call on what settings to use to start, then adjust for best welding.

A little hint using a mig machine with only a few amperage settings. If you have to much heat on the lowest setting, move the gun away from the work. That will effectively lower the guns output. Find the right distance and start welding.

[Dragncar]

If they made .023 flux core it would weld at lower amps than .023 solid core by the book,as sure as the sun is going to come up tomorow.But thet dont.
It is OK to weld a fender with .030 flux core as long as your welder is not a piece of garbage.Its just a fender.
Things like TIG welding stainless is a art form all to itself.

[BILTIT]

Originally Posted by TinInjun

That is the preference I use for welding sheet metal using a TIG machine. Plate steel is a different deal. Thinner sheet has a different heat conductivity than thick plate plate steel. You can use less amperage with the thick stuff as it retains more heat in a smaller area whereas thin sheet will spread the heat out faster so you have to use more amperage than you think you should. 1/4 steel I would be looking at 75 to 80 amps, then fine tune the adjustment when I start welding. Just remember that each type of metal welds differently be it sheet steel , plate steel, aluminum sheet and so on. It is up the the welder to make the call on what settings to use to start, then adjust for best welding.

A little hint using a mig machine with only a few amperage settings. If you have to much heat on the lowest setting, move the gun away from the work. That will effectively lower the guns output. Find the right distance and start welding.

I understand now, thanks for the clarification.

I just noticed today that both miller 180 and the hobart 187 are on sale (100 bucks off) around here (and both machines are the same price, strange). Might be a good time to buy. Seasonal promotion? Maybe someone else can see if they are on sale anywhere else.

[TinInjun]

Originally Posted by Dragncar

.Things like TIG welding stainless is a art form all to itself.

Naw, I love TIG welding stainless. I makes such a pretty weld.
I wish they had made the .030 flux core wire when I started welding body and floor panels. I got stuck having to do it with .035. Its tough but can be done once you figure out the welder setting and gun placement. I love being told it can't be done, then prove it wrong.

[69lm69gp]

Originally Posted by Dragncar

If they made .023 flux core it would weld at lower amps than .023 solid core

You are confusing current with heat. Heat causes blow through not amps, too much heat equals melted metal. As I said in my earlier post, my original statement was wrong. I should have said flux core wire puts too much heat into the weld leading to blow through.

[Dragncar]

69lm69gp,I am not confusing anything.Current-amps are like electricity volume.Compair it to a hi volume hi pressure fuel pump.Amps compair to the volume and voltage would compair to the pressure.The higher you turn up the amps on a welder the more heat you impart on the material.
In welding amps/current = heat.
In a CV welding machine the amps are controlled by the wire speed.
Then you have current slope.
And no,flux core wire does not put too much heat into the weld of a fender to cause blow through.
Just take your finger off the trigger.Its kind of hard to blow through a fender if you are only welding 1/4"-3/8" at a time with the welder on a low setting.Thats how you weld a fender.

[69lm69gp]

"a short circuit transfer with .030-inch solid wire set at 18-19 volts with 160-170 amps and using 75 percent Argon and 25 percent CO2 shielding gas will usually produce little spatter, create a smaller heat affected area and reduce chances of burn-through. As a result, many automotive enthusiasts who specialize in bodywork or those who work with thinner applications prefer solid wire in their operations."

From this article on Miller's web site titled "Solid vs. Flux Cored Wire-When to use Them and Why"

http://www.millerwelds.com/education...article62.html

At this point we will just have to agree to disagree.

[Dragncar]

Dude whats wrong with you.I am trying to tell people its OK to weld a fender with .030 flux core.I myself would rather run .023 solid core,but I have a choice.And I gaurentee that you can run .030 flux core at less than the 18-19 volts with 160-170 amps in your example.
If a novice welder already has a good 110V welder and it is setup for flux core it is fine to weld a fender with it,any spatter is ground off if body work anyway.If the novice wants to spend another 100$ plus on the tank and gauge thats fine and is a good investment,but you do not have to spend it if you do not want to.Flux core is not the Devil,its just another tool.

[69lm69gp]

Originally Posted by Dragncar

you can get away with slightly less heat with solid .023 vs .030 flux core.

This is my point.

My problem is I didn't state that this is the point I was trying to get across (and that I didn't read your response close enough).

Originally Posted by Dragncar

If a novice welder already has a good 110V welder and it is setup for flux core

But the starter of this thread is shopping for a welder. And to him I say get welder that you can add gas to and can handle .023/4 wire. I don't know why you don't what to "mess with gas" but it is really not a big deal.

[Colin]

Originally Posted by TinInjun

Naw, I love TIG welding stainless. I makes such a pretty weld.
I wish they had made the .030 flux core wire when I started welding body and floor panels. I got stuck having to do it with .035. Its tough but can be done once you figure out the welder setting and gun placement. I love being told it can't be done, then prove it wrong.

I love to TIG stainless too...........90% of the TIG welding that I do is with stainless. It is pretty.