MIG for Cast Iron + Small Welding Table

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warmstrong1955
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Re: MIG for Cast Iron + Small Welding Table

Post by warmstrong1955 » Sat Dec 10, 2016 10:13 pm

SteveHGraham wrote:The weld is actually ground flat, but I think I'll add a rubber washer anyway.
See....like fallin' off a piece of cake!

I'd skip the rubber washer(s). Most of the cast foot mounts I've repaired, were due to loose mounting hardware, including those with failed rubber mounts.
If it can move around, it can break.
And I've repaired a bunch....motors, pumps, transmissions, gearboxes......

:)
Bill
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SteveHGraham
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Re: MIG for Cast Iron + Small Welding Table

Post by SteveHGraham » Sat Dec 10, 2016 10:17 pm

Can you explain why this worked? I don't understand it at all.
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warmstrong1955
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Re: MIG for Cast Iron + Small Welding Table

Post by warmstrong1955 » Sat Dec 10, 2016 10:28 pm

SteveHGraham wrote:Can you explain why this worked? I don't understand it at all.
Cast Iron is not created equal. What you had was good stuff. There are some, that if you did what you did, would crack while you were sippin' on your margarita watchin' it cool.
Preheat is important. You did that. Low....but you had some.
Stress relief is important. You did that. Peening of any kind is good.
Multi pass works better than single pass. You did that too.
Stainless will work, with most good castings, and you used it.
Although....stainless with some nickel in it would have been better....but you used hat ya got.
Most rods & wires for cast iron, are 50% nickel or better.
Most that are for welding steels to cast iron, are less nickel.....25% to 45%.
You vee'd out both sides. Good practice.
(FYI You can also vee out one side, run a stringer, and then vee out the opposite side....to keep things all in line.)
No harm in grinding & re-welding. Keeps things warm....and will somewhat blend the parent material with the filler.

Not turning on the gas......no cocktails for you!


Howzatt!
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SteveHGraham
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Re: MIG for Cast Iron + Small Welding Table

Post by SteveHGraham » Sun Dec 11, 2016 10:32 am

Any sissy can weld with the gas on. I'm always looking for a challenge.

Here's what I'm wondering now: if, in the future, I have a situation in which I can't save the missing piece, will I be able to apply stainless weld to the other part, make a stainless replacement piece, and weld it to the stainless filler buildup on the main part?
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warmstrong1955
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Re: MIG for Cast Iron + Small Welding Table

Post by warmstrong1955 » Sun Dec 11, 2016 11:26 am

I've made many missing parts from mild steel and welded them to cast iron, but never stainless.
Stainless is more expensive, harder to work with, and I never saw any reason to use it over mild.

Bill
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SteveHGraham
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Re: MIG for Cast Iron + Small Welding Table

Post by SteveHGraham » Sun Dec 11, 2016 12:01 pm

I'm just trying to think of a material that would weld up well to a cast iron part which has been "tinned" with stainless wire. I figured stainless was the best bet.

It looks like stainless wire is a good thing to use with cast iron, so it just seemed like a stainless part would work well on the other side of the crack.
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warmstrong1955
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Re: MIG for Cast Iron + Small Welding Table

Post by warmstrong1955 » Sun Dec 11, 2016 12:21 pm

It won't matter. What matters is what happens to the cast iron after it welds and cools. If it's already been repaired with 308 or 309, it won't matter.
That's why you want the preheat. less temp difference between the weld being applied, and the cooled temp....less 'damage' to the cast.

Bill
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SteveHGraham
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Re: MIG for Cast Iron + Small Welding Table

Post by SteveHGraham » Sun Dec 11, 2016 12:54 pm

I feel like rounding up some cast iron junk and practicing.

At the very least, I could improve my ability to see the weld puddle, instead of a big red mess that fills the field of view.
Every hard-fried egg began life sunny-side up.

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warmstrong1955
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Re: MIG for Cast Iron + Small Welding Table

Post by warmstrong1955 » Sun Dec 11, 2016 1:05 pm

Nothing wrong with that. A little practice is always good.
No doubt that the weld puddle does not look like one when welding steels. I think I mentioned that before.
You might want to pick up some NI55 and try that too. I know it's available in 2 lb spools. Stainless may work for some cast irons, but I can assure, not for all. Especially exhaust parts, and all the hot/cold cycling they do. That, and many are just plain horrible, and very high in carbon.
Nickel is the preferred filler for cast iron.

Bill
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SteveHGraham
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Re: MIG for Cast Iron + Small Welding Table

Post by SteveHGraham » Sun Dec 11, 2016 1:46 pm

Well, obviously I need a TIG welder and an acetylene rig. I need it BAD. Like NOW.
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warmstrong1955
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Re: MIG for Cast Iron + Small Welding Table

Post by warmstrong1955 » Sun Dec 11, 2016 1:50 pm

Well....of course!
If you get a TIG, you also will have a stick welder....if you shop right!

I have one MIG, that will also stick weld.
One AC/DC TIG, that will also stick weld. (AC for aluminum, DC for steel)
And a baby MIG, Miller 135.
And a oxy-acetylene rig, with cutting and welding/brazing tips.

Why don't you have that stuff already??

;)
Bill
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SteveHGraham
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Re: MIG for Cast Iron + Small Welding Table

Post by SteveHGraham » Sun Dec 11, 2016 2:51 pm

I don't know. It's embarrassing.
Every hard-fried egg began life sunny-side up.

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