Need to get off my butt and practice.

[shenion]

Have had this TIG beast for two years and have only done a few things with it. Then a buddy brings two things by for me to fix.

First was a 21HP B&S engine that threw a rod. Cracked the case. Did not go well, clean with acetone, heat with torch, still could not get past the oil gassing out the crack. MIG failed with cracks, so plan C, mig brazed it.

Now he brought a deck spindle. Should be easier

Came out ok. Probably 60% penetration on the front. I knew I needed more heat; as I mashed the pedal i saw the tungsten melt back. Went slow, but that just makes a wider bead. 1/16" pure tungsten, 1/16" 4043 filler.

Swore, i would order some 3/32 tungstens ASAP. Then found one in my assorted pack, oops

Did both sides, should be strong enough. The deck had cracked and the spindle ripped out the deck. With the deck welded with stiffeners, should have no problems.

Yes, the gusstes on the bottom look sloppy. Did a small weld over the crack, then a bead along the top. Had a nasty habit of dipping the rod and sliding out pulling a glob over the side.

Ok, I need to get more practice. I hate this, small job comes up: "Yea I can do it, just need to practice on something similar first"

So, a bit of practice tonight:

Cut a 1/16" slot in some 1/8" angle iron. 2% Thoriated 3/32 tungsten, 1/16" ER70S-6 filler.

Was so easy, gotta love mild steel TIG. Penetration was just at 100%.

Will try pulsing next with the footpedal. Then comes a scary beast: positional welding

Hmm, from Miller: 2% Thoriated:

"Unlike pure tungsten, these electrodes are only for specialty type AC welding (thin gauge aluminum or materials less than .060-in.), but they are exceptional for DC electrode negative or straight polarity on carbon and stainless steel, nickel and titanium applications."

Was real nice on steel. May try it on thin aluminum. Been using pure (green) electrodes, arc seems real harsh.

Guess I need to set up a list of things to practice. 1/8" steel seems like cheating. Did some 1mm steel and it was much harder.

One thing I need to do is weld to razor blades together (fusion weld). Seems to be a bragging right here in the US

 

[steve202]

Cool.

 

[busa]

Shenion.

This is a method I use on engine case repairs with oil contamination such as the one in your post. If you have good access with the grinder then cut in to the crack and vee it out as deep as you can, obviously there will be some oil left in the crack, most of this can be floated out with the weld pool. Set the Tig up with a fairly low frequency, this will give a wide pool with good depth, the oil will float to the top of the pool like a crusty slag. You can stir the crud and flick most of it out with the filler wire as you go. Once you have finished the first pass then take the grinder and cut it out again and repeat the process. Usually two passes will clean enough of the contaminants out that you can weld the repair successfully. Obviously for this method you need good grinder access, if you can get at both sides with the grinder then so much the better.

Dave

 

[shenion]

I'm loving this!

busa, saounds like a good method. Cutting back would have helped. It was kinda like a windshield rock hit. A 3" spider web if cracks. Could have been done, but did not want to spend that much time on it.

Ok, tired of practicing I have had a desire to build a cart for my plasma cutter. So, sounds like a good project to get some real time on TIG. Will basically be an 18x12x10" cube made of 1" angle iron with some casters:

Really liked doing TIG tacks, just a tiny fusion weld.

Interesting, in the mask it looked like I had a fat MIG weld built up. Turns out they were completely flat. More build up on the back though. Some under cut on one weld.

Ok, those were easy, now do one vertical down:

Not bad, a bit flat. The ends were not lined up perfectly, so welded at a bit of an angle. Finding it hard to see.

I have been avoiding TIG and I had thought it would take a long time to get the "feel". With aluminum, yes it is a bit more difficult. I'm remembering back to my old oxy/MAPP days trying to do welding. Was a bear, not enough heat. Only way to weld was with torch on full. Then you ended up blowing the weld pool around and oxidizing everything.

TIG is like having an ideal torch. Still need coordination, have to stop to feed more wire (gloves are too heavy to get any feel.) Need also to dig out my old barstol. Both hands full, one on pedal make balance an issue at times. Want to put a spring on the footpedal, does not stay off sometimes.

A footpedal is key for me. I have done it without, but end up stopping, running over to the machine and change setting. A pain.
I'm really liking this, so what if it is slow.

Edit: Here's one of the backs of the welds:

 

[Angusdog]

I have been avoiding TIG and I had thought it would take a long time to get the "feel". With aluminum, yes it is a bit more difficult. I'm remembering back to my old oxy/MAPP days trying to do welding. Was a bear, not enough heat. Only way to weld was with torch on full. Then you ended up blowing the weld pool around and oxidizing everything.
<snip>A footpedal is key for me. I have done it without, but end up stopping, running over to the machine and change setting. A pain.
I'm really liking this, so what if it is slow.

I hear you. I've spent the last two evening classes practicing aluminium TIG welding. Boy, it's tough. I eventually managed to get reasonable butt joins, lap joins okay but fillet welds are mental. A footpedal is probably essential for aluminium, but I can do without it now for steel welding. In fact, once you get is dialed in for steel, using the torch trigger can easier as you can concentrate on filler rod and keeping your hand steady.

 

[shenion]

I find aluminum varies immensly on the size/shape/type. 1/8" seems easy. Cast parts are difficult as they are often odd alloys (Zamac! shudder )

Finished up the plasma cart:

First tried a fusion lap weld on one of the castors:

Worked well, the rest I just did small welds to not overheat the bearing.

The welds are becoming more consistent:

All done:

 

[shenion]

Ok, now trying some fillets:

Bit messy, having a hard time seeing and steadying the torch.

The other side went a bit better:

Should cut some bigger pieces to practice on. Only 1.5 inches here.

Oh, for the heck of it, tried running a bead along the edge.

 

[gaz_moose]

how did you stop those small practice bits from going walking when you pushed in the fillr rod

 

[shenion]

They were clamped in a vice.

WHen I cut the angle-iron for the 45 degree cuts for the frames, I had lots of triangle pieces left over. So precticed on a few.