Tig welding to cast iron

[Pete.]

That is awesome, I didn't know they were automatic. You wouldn't happen to have any pictures of the mechanism inside?

It's all internal in a steel block. It's quite basic theough.

Doesn't look like a 540 to me, it must be an early version. Wasn't the design american ? Given to J&S for the war effort or something like that.

Yes, it's an early version. Quite a bit different to others you'll see, but it does say 540 on the casting.

 

[I'm getting on a bit]

As soon as I saw the picture I thought J&S 540

Some cosmetic differences to mine which is around 1950

Is the table deliberately slowed down as it seems very slow

 

[Maker]

It's all internal in a steel block. It's quite basic through.

I've just googled it and seen it's hydraulic, I was expecting it to be mechanical.

 

[I'm getting on a bit]

The way the table moves/feeds across is more impressive to see

 

[Pete.]

As soon as I saw the picture I thought J&S 540

Some cosmetic differences to mine which is around 1950

Is the table deliberately slowed down as it seems very slow

Good spot - I'm running reduced pressure on the oil until my new gauge arrives.

 

[I'm getting on a bit]

I don't remember seeing a pressure gauge on mine although I think I can adjust the pressure

 

[Pete.]

There's a plug above the pressure relief valve right on top of the pump, takes a 1/8" npt fitting. On my machine you can't remove the pump tray without un-screwing the pressure adjuster.

 

[Pete.]

Just wanted to add - thanks to all who offered advice and help. Some good people here

 

[Brad93]

What rods would you advise to weld cast @Richard. ?

 

[Richard.]

Cast iron? If I was welding it Id use Ni50. 50% Ni 50% Fe. Brazing is a less risky way of doing it but I've never brazed it before. I've done quite a few weld repairs on cracks with NiFe filler and been successful. Trick is to do an inch then lightly peen.

 

[Brad93]

Tbh I didn't know you could TIG weld cast I thought it was a too concentrated heat for it. I've got some cast stick rods but handy to know what to use TIG filler wisewise if anything ever comes up.

 

[Richard.]

You can Tig weld it. I repaired a large pulley before Xmas using this meathod. The localised heat is a problem but you must not let it cool quickly it needs a preheat and it needs to be widely spread to avoid uneven contraction as it cools. I take it quite hot (150 plus) . Like I say brazing is better and much less localised but the few ive done ive done with Tig. Don't try and weld long runs as you need to peen it while it's hot and soft. 20-30mm is fine. I have a roll of welding blanket which I rap it in once done to cool it down. If you notice the temp dropping rapidly stop welding and get the heat back on. It must cool slowly.

 

[Screwdriver]

I just cut and paste this from my thread on GarageJournal:

Well I drilled out the holes after carefully lining up with the existing holes and using the hardened jaw as a guide.

Imagine my surprise when it was a mile out! The jaw only fits one way up or it hangs over the edge. WTF? So I double checked the OEM jaw:

OMG! I can hardly believe it. Thats almost a whole millimetre out in just 14mm. What on earth is going on. I'd expect an expensive hardened steel jaw to test the accuracy of my measurements. This throws some of the other stuff into harsh light. The machined step in the jaw faces, the fact that the opposing jaws are nowhere near 180 degrees apart, the anvil not being parallel to the base etc. etc. I had wanted to defend this amazing vice as being the best of British but this particular one is surprisingly crude.
I started to linish the anvil flat but I didn't want to take too much material off. It was about 1-2mm off being parallel with the base so I did most of it and just left it at a slight angle to parallel. I may revisit that.
Still, it's a tool and I can't wait to try it. I'll probably make some HDPE jaws up out of an old chopping board or maybe mahogany. I can't see myself throwing any more money at this though, will be interesting to see how much the new jaws cost.
But hey, it's starting to look nice!

Now I just need to decide if I want to risk another braze to fill up the cracked off back cap retaining screw. I say risk because I don't want to heat up the whole thing just for that small braze right on the end. On the other hand, I do know it's possible to distort and crack castings if you're not careful, plus I'd have to machine off any excess. Maybe I could TIG it using those brass rods??
...
Incredibly, TIG brazing seemed to work! I certainly wouldn't be so casual with anything life threatening but I thought I'd have a go.
From stone cold, 60 amps, AC, with +ve bias and -ve, seemed to go on ok but spatter.
Went to DC which was virtually the same though I think I cranked the amps up a bit. Again lots of noise, spatter and the silicon rod really would boil off in an instant. But it stuck fast! I even managed to braze it with a bolt in situ so I didn't have to muck about trying to find a hole etc. Was a right pig to get it out but it did screw out eventually.
Tidied up with a hand file. Where the TIG hit the cast iron, it went glass hard. Had to dremel a couple of spots off with a stone when I flattened it back. Drilled and tapped the back cap and all went together ok. The grub screws are only there to prevent the front jaw from being pushed into the vice, which is how the postie managed to break it when he dropped it.

Paint prep.

Last look at the repair piece.

And we're nearly there....

Just a pair of jaws to knock up.
S.

 

[Screwdriver]

Thought it might be interesting where I had to braze one part and TIGged another less important, cosmetic issue.

Both repairs turned out to be super strong and the new jaw (I replaced the entire top half) is holding up well.

S.

 

[Richard.]

Thought it might be interesting where I had to braze one part and TIGged another less important, cosmetic issue.

Both repairs turned out to be super strong and the new jaw (I replaced the entire top half) is holding up well.

S.

I remember the thread. Was a great informative read.