Tig welding tips, questions, equipment, applications, instructions, techniques, tig welding machines, troubleshooting tig welding process
Gavin Melville
  • Posts:
  • Joined:
    Fri Jul 03, 2015 6:31 am
  • Location:
    Christchurch, New Zealand

A photo of a bar coaster would be fine. Ms paint is just not the tool - for anything.
User avatar
  • Posts:
  • Joined:
    Thu Jan 06, 2011 11:40 pm
  • Location:
    Near New Orleans

That took a minute... I forgot I needed to reinstall the drivers for my printer/scanner.

Here's a crude sketch, showing a tee joint, and a pipe-to-plate. I've drawn it with a land, rather than a knife-edge, since you're working with aluminum. A knife-edge would just blow out. The bevel will need to be at least 45* up to about 60, depending on the thickness of the material, so you can get in to the corner.

Working with Stainless would require purging the back side of the tee or the inside of the pipe/tube for the first pass, since the material is thinned out enough for full penetration.

Steve S
Scan.jpg
Scan.jpg (23.93 KiB) Viewed 1327 times
Gavin Melville
  • Posts:
  • Joined:
    Fri Jul 03, 2015 6:31 am
  • Location:
    Christchurch, New Zealand

Ok, got that. I'll be at work in an hour and can try it then. I didn't think of that, on the surface it appears to make the problem worse.
User avatar
  • Posts:
  • Joined:
    Thu Jan 06, 2011 11:40 pm
  • Location:
    Near New Orleans

It's not really needed for what you're doing. It's seldom needed unless a procedure calls for it. The trick is to get the tungsten very close when you start your arc, and get both sides of the joint to puddle all the way to the corner. You may have to manipulate the torch, as the arc will favor one side. Once you're molten to the corner on both pieces, add your first dab of rod, drawing the torch back a bit as the puddle will swell rather quickly. Advance to the front edge of the puddle, and don't add rod until you see the previous addition start to flow into the corner. Lather, rinse, repeat.

Steve S
Gavin Melville
  • Posts:
  • Joined:
    Fri Jul 03, 2015 6:31 am
  • Location:
    Christchurch, New Zealand

Thanks Otto,

Fillet joints have always been my nightmare. All other joints, and "open" fillet welds are fine. Once I get to 90 deg it just doesn't work so well. This thread has given me some good ideas.
exnailpounder
  • Posts:
  • Joined:
    Thu Dec 25, 2014 9:25 am
  • Location:
    near Chicago

Otto Nobedder wrote:
exnailpounder wrote:
Otto Nobedder wrote:I see in the original pictures a complete lack of root penetration. I also saw a comment that you can't get root penetration without the weld dropping out.

That's nonsense. I see in the broken weld picture you didn't even nick the edge of the tube. You're building a weld bridge, not making a weld joint. The root must break the edge of that tube if you want strength in the joint.

Steve S
That comment about full pen was me and the truth is you can't get complete pen on a filet. You can cut and etch any filet and see what penetration you get and they are never all the way through, now on a gapped butt weld you can get full pen. If you did get complete pen, that means you would be all the way through 3/16" of wall, into the inside of the tube and then you would have an overheated mess. I suggested the OP was dipping in the keyhole and not letting the puddles join. You have to dip in the keyhole on a butt joint cause thats all you have to dip in. I guess I had typing palsey when I wrote that...alcohol was involved.
What I said didn't quite lead to what I meant. I meant penetrating the full depth of the fillet, fusing the corner of the leg , as opposed to bridging over it and leaving the corner intact. I wasn't trying to imply full penetration.
Sloppy language on my part.

Full penetration can be achieved on a fillet through prep work, by beveling the leg to a small land or a knife edge, though it's not always practical or useful. When both sides of a leg are welded, or in this case the tube is welded 100%, full throat depth is all that's required so your weld is as strong as it's size implies.

Steve S
Out of admiration...I won't make you apologize :lol:
Ifyoucantellmewhatthissaysiwillbuyyouabeer.
exnailpounder
  • Posts:
  • Joined:
    Thu Dec 25, 2014 9:25 am
  • Location:
    near Chicago

Otto Nobedder wrote:That took a minute... I forgot I needed to reinstall the drivers for my printer/scanner.

Here's a crude sketch, showing a tee joint, and a pipe-to-plate. I've drawn it with a land, rather than a knife-edge, since you're working with aluminum. A knife-edge would just blow out. The bevel will need to be at least 45* up to about 60, depending on the thickness of the material, so you can get in to the corner.

Working with Stainless would require purging the back side of the tee or the inside of the pipe/tube for the first pass, since the material is thinned out enough for full penetration.

Steve S
Scan.jpg
Ding dang...you can get a full pen weld on that bad boy. 8-)
Ifyoucantellmewhatthissaysiwillbuyyouabeer.
Gavin Melville
  • Posts:
  • Joined:
    Fri Jul 03, 2015 6:31 am
  • Location:
    Christchurch, New Zealand

Some progress. Back to basics - here is a butt joint welded the same as above, .1 in thick 6061, 100 amps (actually 70 was enough), 120 Hz. I assume that is OK, certainly strong enough.

The fillet joints are still eluding me, will post back when I've got one etched.

It might be the 6261 aluminium that is making things hard - fillet joints with the SHS shown here are better. It's thinner, and also 6061.

I'd like to see a fillet joint snapped or etched - anybody got one ?
Attachments
IMG_1433.JPG
IMG_1433.JPG (15.54 KiB) Viewed 1296 times
User avatar
  • Posts:
  • Joined:
    Thu Jan 06, 2011 11:40 pm
  • Location:
    Near New Orleans

I will try to do a fillet cut and etch tomorrow, as time allows. I have a bit of material set aside, as I wanted to do one today, but I'm pressed pretty tight until after Friday.

The material will be 1/4" 5053, and I will likely weld it with 4043 or 4943, for a good contrast in the etch.

Steve S
exnailpounder
  • Posts:
  • Joined:
    Thu Dec 25, 2014 9:25 am
  • Location:
    near Chicago

20170426_074100.jpg
20170426_074100.jpg (51.18 KiB) Viewed 1283 times
20170426_080658.jpg
20170426_080658.jpg (52.72 KiB) Viewed 1283 times
This doesn't show much but I did the cut and etch. One is tapered like Steve's drawing , the other is just a normal filet. The etching doesn't make the welds stand out really good but both ways get excellent penetration when you allow the 2 puddles to meet and then dip but but the regular fillet has much better penetration into the base metal. I think that is because with the taper, I had to move a little faster to keep from melting back that taper and it actually turns out to be a welding thick to thin scenario and you get a little less penetration on the ticker metal because you don't want to melt you thinner metal and you have to move out quicker. If you dip in the keyhole you are bridging the weld. I don't have any dye penetrant but I suspect you would be able o see the line where the two pieces meet on the normal filet much more than the tapered one.
Unknown base metal .125, 3/32" 4043 filler, 140 amps, pedal, 18cfh, 3/32" 2% lanthanated tungsten (micro balled)
Ifyoucantellmewhatthissaysiwillbuyyouabeer.
User avatar
  • Posts:
  • Joined:
    Thu Jan 06, 2011 11:40 pm
  • Location:
    Near New Orleans

Nice, Jeff, and a great analysis on the base penetration. I think this could be limited with torch angle adjustments, but it may be finer control than a blind shaky guy like me can manage. I won't get to do a cut/etch before Saturday, as there's a priority job right now that's meant to be done Friday, and I always get the priority jobs...

What did you etch with?

Steve S
exnailpounder
  • Posts:
  • Joined:
    Thu Dec 25, 2014 9:25 am
  • Location:
    near Chicago

Otto Nobedder wrote:Nice, Jeff, and a great analysis on the base penetration. I think this could be limited with torch angle adjustments, but it may be finer control than a blind shaky guy like me can manage. I won't get to do a cut/etch before Saturday, as there's a priority job right now that's meant to be done Friday, and I always get the priority jobs...

What did you etch with?

Steve S
I used Naval Jelly and when I thought that didn't do a good job I used oxalic acid( Barkeepers Friend) Not ideal but better than nothing and the details show.
Ifyoucantellmewhatthissaysiwillbuyyouabeer.
User avatar
  • Posts:
  • Joined:
    Thu Jan 06, 2011 11:40 pm
  • Location:
    Near New Orleans

exnailpounder wrote:
Otto Nobedder wrote:Nice, Jeff, and a great analysis on the base penetration. I think this could be limited with torch angle adjustments, but it may be finer control than a blind shaky guy like me can manage. I won't get to do a cut/etch before Saturday, as there's a priority job right now that's meant to be done Friday, and I always get the priority jobs...

What did you etch with?

Steve S
I used Naval Jelly and when I thought that didn't do a good job I used oxalic acid( Barkeepers Friend) Not ideal but better than nothing and the details show.
First thing I'll try is Alubabrite. It quickly etches clean aluminum, but I'm not sure it will contrast the weld nugget. We'll see. I know it works a treat on stainless steel that's had the CrO2 recently buffed off.

Also, I'll be welding known material. 5052 base with 4943 filler.

Will report results, of course.

Steve S
Gavin Melville
  • Posts:
  • Joined:
    Fri Jul 03, 2015 6:31 am
  • Location:
    Christchurch, New Zealand

Don't laugh, but Drain Cleaner works well. :shock:

Just Sodium Hydroxide. Don't breath the vapour.
cj737
  • Posts:
  • Joined:
    Thu Sep 29, 2016 8:59 am

Aerosol oven cleaner too...
User avatar
  • Posts:
  • Joined:
    Thu Jan 06, 2011 11:40 pm
  • Location:
    Near New Orleans

Both those suggestions make sense. Alkaline, rather than acid, might reduce raw aluminum better.
We shall see.

Steve S
Poland308
  • Posts:
  • Joined:
    Thu Sep 10, 2015 8:45 pm
  • Location:
    Iowa

New brite coil cleaner from any hvac supply house. It's alkaline and concentrated. They sell gallons for about $30. It's water soluble. I've seen it eat the aluminum fins off of a condenser coil if left on too long.
I have more questions than answers

Josh
User avatar
  • Posts:
  • Joined:
    Mon Feb 09, 2015 4:48 pm
  • Location:
    St. Johns, Michigan

We use that to clean AC coils, works! :)
Pete



Esab SVI 300, Mig 4HD wire feeder, 30A spool gun, Miller Passport, Dynasty 300 DX, Coolmate 4, Spectrum 2050, C&K Cold Wire feeder WF-3, Black Gold Tungsten Sharperner, Prime Weld 225
User avatar
  • Posts:
  • Joined:
    Thu Jan 06, 2011 11:40 pm
  • Location:
    Near New Orleans

I have a slow-developing etch underway. The oven cleaner appears to be the ticket. If I decide to do this regularly, I'll by a tub of lye.

Steve S
User avatar

Otto Nobedder wrote:I have a slow-developing etch underway. The oven cleaner appears to be the ticket. If I decide to do this regularly, I'll by a tub of lye.

Steve S
Look forward to seeing this, doing a little reading about lye, when in contact with aluminum produces hydrogen gas. :shock:

Steve I've haven't done any etching but am interested in the process, any details are appreciated, maybe even a thread dedicated to this?
Richard
Website
User avatar
  • Posts:
  • Joined:
    Thu Jan 06, 2011 11:40 pm
  • Location:
    Near New Orleans

Here's the etch. The point I was making was breaking the edge of the leg on a Tee joint, and this shows it. I'm a bit disappointed in the penetration on the base, but it's sufficient.
Al Etch.jpg
Al Etch.jpg (35.25 KiB) Viewed 746 times
Steve S
exnailpounder
  • Posts:
  • Joined:
    Thu Dec 25, 2014 9:25 am
  • Location:
    near Chicago

Next to the leg of your tee..on both sides is a little flat spot before the obvious penetration...that's a little bridging and that's hard to avoid when doing thick to thin. I bet if you put some dye penetrant on it, it would show a tiny crack there. You had the same result I had which is when you taper the leg, it becomes a thicker to thinner scenario. I can see where on the right side you concentrated your heat more on the thicker piece...or the metal was just super hot when you welded it. You have to move out so as not to melt the thin leg at the expense of getting less penetration on the thicker piece. I do alot of thick to thin stuff on other metals and I always concentrate the heat on the thick piece and wash up onto the thinner piece but aluminum doesn't work like that. If you're using enough amps to melt 1/4" AL...then those same amps will flat melt out thinner material. I had to weld some .062 box tube AL to 3/16"...what a freaking nightmare...I did it but the thin metal is almost at critical mass before you hardly make a dent in the thicker stuff. There is alot more to welding aluminum than it just looks cool.
Ifyoucantellmewhatthissaysiwillbuyyouabeer.
exnailpounder
  • Posts:
  • Joined:
    Thu Dec 25, 2014 9:25 am
  • Location:
    near Chicago

20170430_110132.jpg
20170430_110132.jpg (41.78 KiB) Viewed 720 times


This is a little blurry because my camera on my phone sux but you can really see the nugget on this one. I used Zep concentrated purple cleaner which has sodium hydroxide in it. Really etches good.
Ifyoucantellmewhatthissaysiwillbuyyouabeer.
User avatar
  • Posts:
  • Joined:
    Thu Jan 06, 2011 11:40 pm
  • Location:
    Near New Orleans

Actually, Jeff, this was prepped square. I did not taper the leg of the tee. I was hoping to demonstrate penetrating into the corner for full depth on the weld, rather than bridging over it with filler. What I think happened was the "table", a slab of 1/2" aluminum, acted as a heat sink and limited my penetration into the base.

Yes, I noticed the little flat spot. In one I broke (I used an L-dog and wedge to dog down a big gap on a doubler, fillet on one side, broke off with hammer after) I noticed molten aluminum wicked into the joint beyond the penetration, giving a distinct appearance of a line of lack of fusion. I wish I'd photo'd that.

Storming like crazy here at the moment, lightning dancing all around. I live among the trees, so that always makes me a bit nervous.

Steve
exnailpounder
  • Posts:
  • Joined:
    Thu Dec 25, 2014 9:25 am
  • Location:
    near Chicago

Otto Nobedder wrote:Actually, Jeff, this was prepped square. I did not taper the leg of the tee. I was hoping to demonstrate penetrating into the corner for full depth on the weld, rather than bridging over it with filler. What I think happened was the "table", a slab of 1/2" aluminum, acted as a heat sink and limited my penetration into the base.

Yes, I noticed the little flat spot. In one I broke (I used an L-dog and wedge to dog down a big gap on a doubler, fillet on one side, broke off with hammer after) I noticed molten aluminum wicked into the joint beyond the penetration, giving a distinct appearance of a line of lack of fusion. I wish I'd photo'd that.

Storming like crazy here at the moment, lightning dancing all around. I live among the trees, so that always makes me a bit nervous.

Steve
My second pic is the same as yours. I didn't taper either but it just hit me...if we did taper and this was our weld profile, we would have had almost no penetration into the leg of the T. But if you look at my first attempt, you can see very obvious lack of penetration on the bottom of the T on the tapered one and come to think of it...I welded on a big slab of 3/4" AL myself...wonder if that could have skewed anything? This cutting and etching sure is an eye opener. I don't weld AL very much but I will pay more attention from now on.
Ifyoucantellmewhatthissaysiwillbuyyouabeer.
Post Reply