Chinese steel ?

Some may recall a few months ago while I was building the rooster weather vane that I had porosity problems while TIG welding some hot rolled steel . Well , it happened again today . I noticed yesterday that the tension rods on my HF hydraulic jack press had dimpled the underside of the top beam . I decided to cut the dimpled area out and weld in a thicker piece since I'm using a bigger jack than it came with . I milled out a square section of the bottom of the 3/16 inch thick square tube and welded a 1/2 inch thick piece in it's place . I wanted to TIG it for better penetration , but it was not going to happen . I ran a couple of beads and could tell right away that it wasn't a weld I'd trust , so I fired up the BabyMIG and welded it with .025" ER70S6 shielded with straight CO2 - ground the porous welds out and redid them with MIG too . Watched the puddle closely to be sure I was getting good fusion , this thing has a 20 ton jack and the last thing I need is for it to give under load . I should probably drop back to the 12 ton I had on it but the 20 doesn't leak around the pump cylinder .

Reply to
Snag
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Some may recall a few months ago while I was building the rooster weather vane that I had porosity problems while TIG welding some hot rolled steel . Well , it happened again today . I noticed yesterday that the tension rods on my HF hydraulic jack press had dimpled the underside of the top beam . I decided to cut the dimpled area out and weld in a thicker piece since I'm using a bigger jack than it came with . I milled out a square section of the bottom of the 3/16 inch thick square tube and welded a 1/2 inch thick piece in it's place . I wanted to TIG it for better penetration , but it was not going to happen . I ran a couple of beads and could tell right away that it wasn't a weld I'd trust , so I fired up the BabyMIG and welded it with .025" ER70S6 shielded with straight CO2 - ground the porous welds out and redid them with MIG too . Watched the puddle closely to be sure I was getting good fusion , this thing has a 20 ton jack and the last thing I need is for it to give under load . I should probably drop back to the 12 ton I had on it but the 20 doesn't leak around the pump cylinder .

Reply to
Jim Wilkins

Snag, I have torn my 12 ton press apart with a 12 ton jack and bent the beam on my 20 ton press with a 20 ton jack. (Both repaired) If you have a cheaper import press like many of use do if you ever push it you may find similar issues, and an oversize jack will certainly tear it apart on a really stubborn u-joint.

As to TIG. You can get ER70S6 TIG rod. AS near as I can tell ER70S2 which is more common in my local welding supply stores requires really clean and properly prepared steel for most of us (well me) to get good welds, but ER70S6 is a little more forgiving.

So far I have mostly used my TIG welder for autogenous (??) welds to permanently lock press fit or tight fitting parts, but I do have both ER70S2 and ER70S6 rod on hand.

I'm not a welder, so take my comments to be worth no more than you paid for them.

Reply to
Bob La Londe

Snag, I have torn my 12 ton press apart with a 12 ton jack and bent the beam on my 20 ton press with a 20 ton jack. (Both repaired) If you have a cheaper import press like many of use do if you ever push it you may find similar issues, and an oversize jack will certainly tear it apart on a really stubborn u-joint.

------------------ The minimum yield strength for pipe on this page is 25,000 PSI which I've seen elsewhere as a good value to take for untested recycled scrap steel. The presses may have been made from the same low-cost scrap.

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Steel recovered from the Titanic showed higher yield strength within the original spec of "15-20 tonnes per inch squared".

Reply to
Jim Wilkins

... an oversize jack will certainly tear it apart on a really stubborn u-joint.

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They are less stubborn if you see and remove the snap ring.

I maxed out my press on a U-joint for a friend of a neighbor. Later they found out that heating it to melt the plastic retainer made the job easy.

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Reply to
Jim Wilkins

I liked the bit about heating it until the grease blows up and spits the cap through the neighbors window across the street.

Reply to
Bob La Londe

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