Brazing/welding cast iron/steel

[Meat Man]

Little off topic, but still "shop" related. I have an bearing holder off an old electric motor that I need to patch back together. The motor fell over backwards and broke the end cap broke into three pieces. I've got the pieces all back together and it fits nice, alignment of the armeture is good. Now just need to stick it together permenant.

First, need to determine what type of metal it is. It's cast, it IS magnetic. Does that rule out cast iron? The inner core of the metal is gray color. Part of the piece is machined flat and the surface looks really smooth. I'm thinking it's cast steel, but not sure what other tests there are.

Second, what say ye on how to fix it? Weld (what process) or braze. Old timer friend wants to braze it, said he has good luck with it. Took it to a pro welder and he thought it would be weldable, but didn't sound 100%.

BTW, it's not oil impregnated.

[CRO]

I would weld it up with some nickel rod for Cast Iron repair... just check the description on the rods to be sure that the weld will be machinable afterwards.. use the wrong rod and the edges of the weld will be too hard to machine should you need to send the end plate for a ride in the lathe to true it up.

http://uniweld.com/catalog/alloys/maintenance_repair/cast_iron_alloys.htm

[jpmassey]

Nickel 99, TIG welded, with a good amount of cleaning and preheat.

[45acp]

Hit it with a grinder. If the sparks are red, its cast iron. If they are orange, its cast steel.

[Rory Bellows]

I would let the old timer friend braze it. I just brazed a handle off an old south bend lathe with good results and I suck at brazing.

[BumpyDodge]

... It's cast, it IS magnetic. Does that rule out cast iron? ...

When did iron become non-magnetic? :flipoff2:

[billybob_81067]

Braze it and be done with it...

[Wyoming9]

All the above are good options.

I myself would go with braze for what its worth :D

[Meat Man]

did a little investigating.

I drilled a 3/32" hole, I got a little bit of powder but mostly small V shaped chips. Looked a little like the chips that come out just before a long ribbon of swarf when drilling mild steel.

I also ground on it a little. I used a fresh grinding wheel in my 4.5" grinder (regular hard wheel, not a flap wheel) and a 3" pneumatic cut-off. I got orange colored sparks.

I agree with BumpyDodge, I thought cast iron should be magnetic. The pro welder I took it to made the comment about non-magnetic cast iron. Maybe he was trying to rule out pot metal. :confused:

Thanks for the input so far. How do my latest findings change the situation? Right now I'm leaning towards brazing it.

[gunsablazin]

Braze it.

[jpmassey]

Nickel!

[sn0border88]

or you could use an O/A torch and cast iron rod to weld it, it actually works pretty good.

[actionpaintball]

chamfer, preheat. preheat some more, nickel rod, post heat

[Meat Man]

Brazed it, worked like a champ.

I actually tack welded the pieces with my MIG just because the fell apart once. V'ed open the cracks, brushed away all debris, preheated on my BBQ (low heat), brazed, put back in BBQ to cool down slow.

The bore for the bearing shrunk a little, but I just hit it a little with a sanding drum. Alignment seems OK on everything.

Thanks for the help.