It's the steel !

I did the test someone suggested to check for shield gas with my TIG , it was getting gas to the nozzle . So I tried a few things , different filler , different steel piece ... and it turns out the 3x 1/4 steel I used is the problem . With no filler , just melt a puddle and chase it a couple of inches and there were all kinds of craters . Different steel welded nicely and had no problems . Strange , that steel welds right pretty with the MIG . I'm still going to pick up a new bottle tomorrow ... along with a trip to the LPG store and the grocery store . Hmmm , I should probably fill my gasoline cans too .

Reply to
Snag
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I did the test someone suggested to check for shield gas with my TIG , it was getting gas to the nozzle . So I tried a few things , different filler , different steel piece ... and it turns out the 3x 1/4 steel I used is the problem . With no filler , just melt a puddle and chase it a couple of inches and there were all kinds of craters . Different steel welded nicely and had no problems . Strange , that steel welds right pretty with the MIG . I'm still going to pick up a new bottle tomorrow ... along with a trip to the LPG store and the grocery store . Hmmm , I should probably fill my gasoline cans too .

Reply to
Jim Wilkins

---------------------- A possible reason:

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This is a piece of common hot rolled steel ... that first article gave some insights into the problem . I won't be using the TIG welder on it , got a couple of welds still to do for the weathercock mount and I'll just use the MIG .

Reply to
Snag

When I lived in the US and was doing machining training I turned a

along the axis of the part on the surface, I questioned the instructor and he was puzzled but we figured in the end it was slag or porosity in the melt being drawn out when the steel was rolled into bar stock leading to small voids/inclusions in the material. I think I've only seen it once since in the UK and I have no idea of how it might effect welds. I've welded many hot rolled and cold rolled pieces subsequently in the UK without issue although I have seen some products that must

cracked in use due to the contamination.

Reply to
David Billington

I thought all concast (continuously cast) steels are "killed" "flat" - and all general steels these days are concast?

These articles describe what did happen in history, when general steels were ingot cast?

???

Rich S

Reply to
Richard Smith

I thought all concast (continuously cast) steels are "killed" "flat" - and all general steels these days are concast?

These articles describe what did happen in history, when general steels were ingot cast?

???

Rich S

--------------

Britannica gives about 55% concast.

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Reply to
Jim Wilkins

"Wide end up" ingot casting is expensive and uses exothermic capping to avoid vast "pipes" etc. Yield only about 80% at best given that.

"Balanced" narrow end up, direct pour into ingot mould - high yield - something in the upper 90's percent? (no experience of ...) ("balanced" equals fizzes out just the right amount of gas to offset shrinkage on cooling and solidification)

But that oxide reaction means the steel cannot be "clean" (it's got a lot of oxide inclusions).

"concast" - benefits from increase in performance of refractories. You can only "concast" fully "killed" steel - (fully deoxidised). You get high yield with concast, with that "killed" steel. Then it gets better, as I understand it. With the performance of current refractories, after the arc furnace (scrap melt) or the converter (first melt in blast furnace), you can tip that initial steel into a ladle-furnace and set up a ferociously cleansing reducing chemically basic slag. Plus in no-oxygen condition, can inject thing like calcium as mega refiner. So when "concast" - getting that high yield - things are highly stacked in your favour...

Is that as you understand?

Rich Smith

Reply to
Richard Smith

"Wide end up" ingot casting is expensive and uses exothermic capping to avoid vast "pipes" etc. Yield only about 80% at best given that.

"Balanced" narrow end up, direct pour into ingot mould - high yield - something in the upper 90's percent? (no experience of ...) ("balanced" equals fizzes out just the right amount of gas to offset shrinkage on cooling and solidification)

But that oxide reaction means the steel cannot be "clean" (it's got a lot of oxide inclusions).

"concast" - benefits from increase in performance of refractories. You can only "concast" fully "killed" steel - (fully deoxidised). You get high yield with concast, with that "killed" steel. Then it gets better, as I understand it. With the performance of current refractories, after the arc furnace (scrap melt) or the converter (first melt in blast furnace), you can tip that initial steel into a ladle-furnace and set up a ferociously cleansing reducing chemically basic slag. Plus in no-oxygen condition, can inject thing like calcium as mega refiner. So when "concast" - getting that high yield - things are highly stacked in your favour...

Is that as you understand?

Rich Smith

------------------------------- Most of my steel making knowledge dates from a Materials Science course in the 1960's. I remember oscillating water cooled copper molds and not much more. After graduation the Army tempted me into computer electronics where I stayed.

Reply to
Jim Wilkins

TIG weld with 70S6 filler rod. 70S6 filler has the highest amount of de-oxidizers and works good with steel that's not perfect.

In my limited experience hot rolled generally welds worse than cold rolled, a de-oxidizing filler is required.

Randy Remove 333 to reply. Randy

Reply to
Randy333

The TIG filler I have is 70S2 , the MIG wire is 70S6 , maybe that's why it was more easily weldable with the MIG . Either way , the weather vane is finished and mounted on the house now . And apparently I got it perfectly plumb on the first try , seems every time I look at it it's pointing a different direction . Not settling to the same position is a good thing .

Reply to
Snag

How do you know it's not gremlins pushing your vane around? It could happen. Just ask William Shatner. Eric

Reply to
etpm

Well , they must be mighty damn quick if that's the answer ! So fast that you can't see 'em doing their dirty little tricks , I've watched it move with wind changes and I haven't seen the little buggers .

Reply to
Snag

On 1/29/2021 11:25 AM, snipped-for-privacy@whidbey.com wrote: ...

Well , they must be mighty damn quick if that's the answer ! So fast that you can't see 'em doing their dirty little tricks , I've watched it move with wind changes and I haven't seen the little buggers .

Reply to
Jim Wilkins

You know at my local welding supply (the good one) I asked for some 70S6 TIG rod and they acted like I didn't know any better. I asked the store manager what the difference was, and he said basically the same thing.

70S6 was for metal with light mill scale or not totally cleaned up. 70S2 requires clean metal.
Reply to
Bob La Londe

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