Ask your WELDING questions here.

[WIsixfitty]

my general filler rule of thumb is rod diameter is dictated by the gap being filled.

obviosuly on thicker materials...

so using mig and regualr wire/rod I have .030, .045, .062, .090, .125 in stainless and mild. Alum .045, .062, .090.


As for tungsten diameter I use .090 for everything. Until about two years ago I did'nt even know they made tungsten in different diameters.

I do have some .062 I tried on some thin stuff. It works nice but I don't take the time to switch it out.

[KTM640Dakar]

Originally Posted by fxstbiluigi

mig wire will cause problems (porosity) you need E-70-S2 for fill wire.
And use some emery cloth to clean the gold colored protective coating off,
Then wipe the fill wire with acetone to further clean it.
Make sure the weld area is bright shiny metal, no mill scale on anything,
and clean with acetone before welding.

You can use MIG wire to use as a TIG filler. Its just too thin for most applications and TIG rods come in handy 36 inch precut lengths. You can get ER70S-2 filler wire in TIG cut lengths and as a MIG wire.

Lincoln Electric Makes welding rod in Mentor Ohio USA.

[grizzzly]

a buddy sent me this

I have been tig welding for about 25 years. My current rig (Lincoln) I've had for about 4 years and have not had any trouble with it prior to this. I weld about once a month so I get in a fair amount of practice. I have always had consistently good welds with a few exceptions when I try to weld something that is too dirty or oily. When that happened in the past, I stop, do a half-assed clean-up, and that usually fixes it. I just finished a project that I started with Tig but had to finish with stick because of porous welds. Not just a few bubbles but MOSTLY bubbles. I would sometimes be able to weld one section with no problems, then move to another part only to have massive bubble problems. The project was mild steel, cold rolled, all 1/4" thick. Some metal had lubricant used on it and some had primer paint. I used a grinder to remove that paint but it didn't matter. To remove the oil residue, I bought a sand blaster just for this project which I was sure would fix it, followed by solvent cleaning but there was no difference. I want to emphasize that some welds came out just fine (about a third of them). If they started good, they stay good for the whole bead but when it starts bad, it never got better.

The gas bubbles in the weld persisted no matter how long of a bead I laid down and no matter what sort of filler rod I used.
There is no difference when I changed out the tungsten to a new one (I use 1/8" 2% thoriated and a screen gas diffuser on a water-cooled torch)
I used a new gas bottle of pure argon (from Airgas) at 15 cfh flow with preflow and post flow.

The only things that I can think of are: 1) the argon gas bottle is new but can't imagine how a fresh bottle would be contaminated or mislabeled or 2) I didn't clean enough but based on experience, I did a pretty good job - I could have done a little bit better but not much.

Can you diagnose what is happening from what I've told you? Have you ever heard of a bad batch of argon???? I've never had one.

Thanks for your help.


i am thinking that he has a water leak, any other thoughts

[David R]

Reply to above.

Draft?

Porosity is usually associated with lack of shielding gas. A hole in the gas line could allow a little fresh air in the line.

I would test the system completely for leaks.

TOO much gas flow can also cause turbulance in the area being welded so the shielding gas mixes with o2 while welding.

David

[grizzzly]

He just sent me a little more information

I never have used 6011. I use 7018. I did not take pictures of the welds before I took it to Tucson but they were full of large collapsed bubbles. 7018 seemed to work fine with no problems.
The water: I see no leaks. However, please explain why you suggest this. How can a leak cause this? If there was no water, the tungsten would melt or get way too hot and I would see that. Even if too hot, it shouldn't change the weld. Are you saying the water could be somehow getting into the arc?? The connections are on the handle, away from the head.
The gas: I see no changes in the gas line. Not sure how I would check for a leak

[the_gr8t_waldo]

i have a different sorta welding question for thoes who are as cheap as me.... first the project- a 14' hand railing to service the main stair case in my home. some peices are bent, while others are welded. up till now i have carryed the project into the garage for the stick welding. but with each trip the project is getting heavyer. and my helper is starting to baulk about this process taking many trips into the garage n back for the next step in the assembly process. btw helper is the g.f.- so you can probably understand the stresses involved.. so i've come to the conclusion that i'll have to limit the trips by tac welding things together in place- this will help a lot with accuracy too. trouble is that there's a lot of finnished surfaces in the new welding area( i would love to avoid additional work by protecting the area). i have worked in industry and on site work they mostly use a fiberglass cloth that works well to protect- this would be my first choice, but i'm on a self imposed mandate to NOT buy anything if i can use something that i alread have on hand or can get for free.( lacking that, buy and trash as a last resort) i have a bit of cotton canvas going unused and would think that after wetting out would be good enough . i also have a few of the plastic tarps that i wouldn't mind sacrificing to the cause. can anyone suggest other mat'ls to protect ? after each bit of welding the protection mat'ls will be taken outside and sprayed with water, then allowed to dry - fire protection for sure!

[Tepi]

Hmmm, most (but not all) of the Heliarc (or as you kids call it: TIG) machines I've ever used, have a pedal that allows me to precisely control my heat.

I've never heard it called Heliarc here in europe and my machine is old school, yes theres a pedal port on it, no I dont have a pedal and no my powersupplies dont support a pedal... Like I said its old school. 3-phase 400V DC and a 2-phase 400V 50Hz AC powersupply converted from a welding transformer (aka buzzbox), but works fine for what it is.

[Strong Bad]

Originally Posted by Tepi

I've never heard it called Heliarc here in europe and my machine is old school, yes theres a pedal port on it, no I dont have a pedal and no my powersupplies dont support a pedal... Like I said its old school. 3-phase 400V DC and a 2-phase 400V 50Hz AC powersupply converted from a welding transformer (aka buzzbox), but works fine for what it is.

I have used converted buzzboxes to Tig weld (had a switch on the handle to turn the gas on and off and scratch start), but I was able to walk over to the machine and turn the amps down so as not "blow through"............. jeez.

Use arc length to micro-control the heat just like you do with stick welding.

[grizzzly]

he just sent me this and a few pictures

I took apart my torch bundle to look for a gas leak today. No leaks. The lines all look brand new and undamaged. I hardly ever unroll it. No gas leak. No water leak. I am pretty sure it has to be a material problem. What do you think? Some steel I can weld just fine. On some steel, I can weld in one place but not another on the same piece. I welded on some stainless steel today and it welded fine. Switched to mild steel and no go.


How do you clean mild steel for welding? I used a bead blaster when I worked at LANL but I cannot afford the floor space now. They are huge. I bought a sand blaster but that is slow, dirty, and often difficult to maneuver the item around to get all angles clean.


I have never had mild steel behave this badly before and even when it did, I could always easily clean it with a wire brush and it welded fine. Now I cannot weld any mild steel. Any other ideas? I am very frustrated!


Jack




Bad weld made today





Same Bad weld made today





Good weld made on same piece of metal. Done two months ago.





Showing same piece of metal with good weld and a bad weld. The big chunk of metal missing on the upper left was because of porous welds - I cut it out thinking I could use filler rod to replace the bad metal but it didn't work.



Another Bad weld on two pieces of metal unrelated to the other ones. Made today.





GOOD weld on stainless steel made today.

[KTM640Dakar]

I can't see your pics but you probably have bad gas or the gas is not getting to the weld puddle.

Check to see if gas is coming out. Set regulator to 25cfh on the regulator. Maybe your regulator is bad.

Make sure your gas is 100% argon.

Your porosity problem is shielding gas related.

Heliarc is a trade name developed in the 60's to describe tig welding with 100% Helium shielding gas.

[Lomax]

I have a small crack in the mounting flange on my R100RS side bag rack. It is chrome plated.

Do I need to get all the chrome off before hitting it with a mild steel wire feed??

Marc

[grizzzly]

Originally Posted by KTM640Dakar

I can't see your pics
Make sure your gas is 100% argon.

are these pictures better?
he did get a new bottle recently

[grizzzly]

Originally Posted by Lomax

I have a small crack in the mounting flange on my R100RS side bag rack. It is chrome plated.

Do I need to get all the chrome off before hitting it with a mild steel wire feed??

Marc

the cleaner the better

[David R]

My first guess is the gas solenoid is not turning on every time.

When its right, its OK, when its wrong its totally messed up.

Shielding gas

David

[rd1900]

Originally Posted by the_gr8t_waldo

i have a different sorta welding question for thoes who are as cheap as me.... first the project- a 14' hand railing to service the main stair case in my home. some peices are bent, while others are welded. up till now i have carryed the project into the garage for the stick welding. but with each trip the project is getting heavyer. and my helper is starting to baulk about this process taking many trips into the garage n back for the next step in the assembly process. btw helper is the g.f.- so you can probably understand the stresses involved.. so i've come to the conclusion that i'll have to limit the trips by tac welding things together in place- this will help a lot with accuracy too. trouble is that there's a lot of finnished surfaces in the new welding area( i would love to avoid additional work by protecting the area). i have worked in industry and on site work they mostly use a fiberglass cloth that works well to protect- this would be my first choice, but i'm on a self imposed mandate to NOT buy anything if i can use something that i alread have on hand or can get for free.( lacking that, buy and trash as a last resort) i have a bit of cotton canvas going unused and would think that after wetting out would be good enough . i also have a few of the plastic tarps that i wouldn't mind sacrificing to the cause. can anyone suggest other mat'ls to protect ? after each bit of welding the protection mat'ls will be taken outside and sprayed with water, then allowed to dry - fire protection for sure!

You can get a weld-resistant tarp cheap at Harbor Freight.
http://www.harborfreight.com/welding...ket-67833.html