Can a hard bearing ball be welded to mild steel

I tried it with a belt-driven lathe, couldn't get the metal red-hot without the help of a propane torch. The pieces stuck together but broke apart easily.

Unless the rod is well and closely supported it tends to bend and run eccentric once the surfaces start to gall together.

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You have no idea!

This is actually how the long shafts on many modern day jet aircraft engines are joined. I'm not sure exactly how many are, but I have seen the Pratt & Whitney promo video on this being done on the JT8-217 engine, and was told at the time it was also used on it's little brother, the JT8-D as well.

Theses engines were made famous on the McDonnell Douglass MD-80, and Boeing

727 aircraft.

It's really a pretty amazing process.

Reply to
Watson
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I use drillpress vises, visegrips and sometimes magnets.

Reply to
Don Foreman

I used a magnet and the welding clamp to set that stuff on the table aligned. Then I tack welded them (required no physical contact and no movement) and then I could do whatever I wanted with them.

Reply to
Ignoramus32330

Great Suggestions on how to keep things in place while welding them...

I used a 45 degree magnet and similar stuff to hold a number of pieces together but I did notice that the magnet will certainly melt with any substantial heat from either the torch or the MIG. I'm going to try a few things and see if I can't come up with some kind of 'Third Hand System" to assist with that...

One thing that drives me nuts is that I always seem to have a problem getting metal pieces at the proper angles ('straight up and down or across').... An example of this would be tacking and subsequently welding 4 - 36" angle iron pieces to plate steel to be used as legs on a table. I can never seem to get the SOB's perfectly (or near perfectly..) straight ! Is there a trick to welding legs onto plate or other angle while keeping them really straight ?

Cheers,

/Jman...

Reply to
Jman

I tack weld the pieces lightly, then bend them into position and hold them there with diagonal braces clamped to the other tack-welded parts.

Reply to
Jim Wilkins

Jig things so the legs are square in two dimensions. Tack weld. Correct out-of-square condition with taps and bumps. Finish weld. Correct out-of-square condition with large hammer and/or hydraulics.

Reply to
Don Foreman

And P&W has a contract to re-engine the Joint-Stars 135's (aka 707) with the JT8D-219 (19 x 4 + spares). First application of the JT8D to the 707 family.

scott

Reply to
Scott Lurndal

| >> In mass production, this would be welded by spinning the | >> rod very fast, then forcing it against the (stationary) ball. | >

| >I tried it with a belt-driven lathe, couldn't get the metal red-hot | >without the help of a propane torch. The pieces stuck together but | >broke apart easily. | >

| >Unless the rod is well and closely supported it tends to bend and run | >eccentric once the surfaces start to gall together. | >

| >---------------------------------------------------------------- | >

| >You have no idea! | >

| >This is actually how the long shafts on many modern day jet aircraft engines | >are joined. I'm not sure exactly how many are, but I have seen the Pratt & | >Whitney promo video on this being done on the JT8-217 engine, and was told | >at the time it was also used on it's little brother, the JT8-D as well. | >

| >Theses engines were made famous on the McDonnell Douglass MD-80, and Boeing | >727 aircraft. | | And P&W has a contract to re-engine the Joint-Stars 135's (aka 707) | with the JT8D-219 (19 x 4 + spares). First application of the JT8D to | the 707 family. | | scott

They are going to hang 4 - 219s on the old 707 tankers?? What a hoot! They will probably be able to fill the entire fuse with fuel.

Reply to
Watson

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