MIG for Cast Iron + Small Welding Table

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SteveHGraham
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Re: MIG for Cast Iron + Small Welding Table

Post by SteveHGraham »

Well, if you use step clamps, you can swing them out a good distance from the slots, in wide arcs.

I don't see any reason to cut the plate or mess with the taper. I should be able to rely on the outer threads. But I suppose I would need a big piece of aluminum to make an internal thread that big. I would probably have to pay for that instead of finding it in my garage.

It would be neat if my Clausing lathe experience turned out to produce something useful instead of just the current feelings of being cheated and abused.

I can get steel disks on Ebay for around $30, but it seems like they're all A36 which is supposedly the worst steel in the universe.
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warmstrong1955
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Re: MIG for Cast Iron + Small Welding Table

Post by warmstrong1955 »

SteveHGraham wrote: I can get steel disks on Ebay for around $30, but it seems like they're all A36 which is supposedly the worst steel in the universe.

:shock:
The worst steel in the universe? Why is that?
It is the most common.

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

Post by SteveHGraham »

A36 is supposed to be harder to machine than 1018, and 1018, in my experience, is nothing to write home about. I haven't bought any A36, so maybe someone who uses it will chime in and tell how wonderful it is.
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warmstrong1955
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Re: MIG for Cast Iron + Small Welding Table

Post by warmstrong1955 »

I make a whole lotta parts for heavy equipment from A36, and A572 gr50....which machines no differently than A36.
Not a lot of difference machining A36, or 10XX steels, low carbon stuff tends to tear, & chip weld.
I work with all....a lot.

It can be done, and quite nicely, and it would be a good idea for you to learn. If you can machine the harder more difficult materials, and get a good finish, you will be better off, and smarter. The easier stuff will be that much easier. A36 is everywhere, and cheap.
I know you are into cheap! ;)

An A36 articulation bearing insert for a 2yd3 LHD:

Lovely what they burn for me to work with, no?
Before.jpg
Cut dry, other than final cuts with a little oil. A little deburring, but no polishing.
After.jpg
Bill
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SteveHGraham
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Re: MIG for Cast Iron + Small Welding Table

Post by SteveHGraham »

Have they ever told you what they have against you?
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warmstrong1955
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Re: MIG for Cast Iron + Small Welding Table

Post by warmstrong1955 »

SteveHGraham wrote:Have they ever told you what they have against you?
I used to get some with warnings..... (The writing was absolutely correct.....the holes were NOT in center)
EOD Bucket Bosses.jpg
They are smarter now......the fab shop bought out a machine shop, just when I was getting used to the sound of ka-thump ka-thump ka-thump!
I priced things accordingly, based on the ka-thump ka-thump ka-thumps required. Time is time, plus materials. My formula is basic, and easy.
They sent their new machinists, the same fine specimens to be turned into something that resembled a species worthy of not being thrown in the scrap iron bin, or tied to a chain for a boat anchor, as they had been sending me.
There were words! Un-pretty!
I had some fun meetings with the owner, and the new machine shop kids.
Generally speaking, fab guys don't communicate with machinists, or visa versa.
My prices seemed really good after that......
Changes were made.....and I still do some overflow parts now, when they can't....starting with much more pleasant raw material to work with.

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

Post by spro »

I'm dazzled and inspired. At the same time, S.G. , I understand the dilemma because the plate is right there. Since you mentioned "stand off" clamps and things, the plate itself may not receive too much heat. Since you already built a wood turning fixture, a tapered hardwood plug to fit the plate would be possible. I would say it be sleeved with brass sheet, as certain woods are acidic and further insulate the wooden taper. Compression upon the taper itself would hold the plate tight enough for mig weld positioning. Something else will turn up but you could try it.
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Re: MIG for Cast Iron + Small Welding Table

Post by scmods »

I didn't watch the video, but there are only so many ways to deal with carbide precipitation in cast iron welding, which is the overriding problem. As the parts involved get larger the chilling effect of the bulk metal complicate efforts to get a good weld. Nickel fillers seem to make things easier, possibly because the nickel may give the weld material a certain amount of added ductility, alleviating cracking issues, but they should not be viewed as a panacea. Basic metallurgical practices still apply, were talking Mother Nature here.

That aside, why not turn an arbor to fit the thread of the faceplate, and mount that in some kind of bearing assembly, like a hub from a front wheel drive auto, so it will rotate. Maybe set it up with an old Amptrol and a series motor, for variable speed without VFD. Be a good project. If you are arc welding on it, try covering it with copper sheet from a sheet metal shop and the spatter won't stick.

Have fun!

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SteveHGraham
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Re: MIG for Cast Iron + Small Welding Table

Post by SteveHGraham »

scmods wrote:That aside, why not turn an arbor to fit the thread of the faceplate, and mount that in some kind of bearing assembly, like a hub from a front wheel drive auto, so it will rotate.
That's actually what I mentioned above. Avoid cutting the faceplate entirely.
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SteveHGraham
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Re: MIG for Cast Iron + Small Welding Table

Post by SteveHGraham »

I'm proud to announce that I succeeded in welding the motor casing back together. Actually, "proud" is misleading. I'm amazed. I don't understand why it worked.

I decided to try the strange method I read about somewhere on the web. I heated the part to above 100 degrees (not 300 or 400). I ground out shallow v's on both sides of the break. I was afraid to make them deep because it was hard to hold everything in place without a lot of matching material on both sides. I used a Bessey clamp to keep them in place for the first two tacks. I welded with MIG, using 308L wire (non-magnetic stainless). I made very small welds and beat them with a hammer when I put the torch down.

The first two welds were just a bit sloppy, because, as always, I forgot to turn the gas on. Also, I foolishly believed some guy who said to use a high wire speed. I had to grind a lot of crap off, but strangely, the welds never popped, and they held so well I was able to take the clamp off.

Because I never practice, I had the usual issues of barely being able to see and occasionally welding in the wrong places, but it worked out okay. I was able to grind the globs down fairly even with the cast iron.

It looks terrible, but I was not able to budge the metal by beating on it with the hammer handle or yanking on it with my hands, so I think it will work well enough for a motor base.

I don't understand why the welds didn't try to pop off. Is it because they're shallow? Should I expect the welds to explode later? They're already cool.

Is it possible that the method I read about for cast iron actually works? That would be nice, because it was very easy.
12-10-16 mitsubishi motor mount MIG welded 308L wire small.jpg
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spro
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Re: MIG for Cast Iron + Small Welding Table

Post by spro »

Congrats on your success! You may want to use a custom washer to engage/allow the stepped weld but otherwise, you have the fourth foot!
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SteveHGraham
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Re: MIG for Cast Iron + Small Welding Table

Post by SteveHGraham »

The weld is actually ground flat, but I think I'll add a rubber washer anyway.
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