welding cast steel

[dbanka]

Hey, hope someone can read this.....This is the first time I've every done this so with a little help maybe I'll be able to read what everyone has to say. OK, here's my problem....I have purchased a trip hammer and part of the casting is broken, near where the die attached. I don't have the piece that come out of the broken area, about 3"x4" which is part of the key way that hows in the hammer die. I been told the casting is cast steel and not cast iron. Because of its location I think I want to weld it and not braze it. OK, a few questions.....
1) Can I cut the area with a cutting torch
2) Can it be welded back with normal welding rod...7018 or 6011 or wire
3) Do I need to preheat the area with a torch or do anything special before or after welding it.
4) Can I weld a solid piece of plate into the damaged area and then trim it to shape after it cools

[HWooldridge]

A pic of the break and the hammer would help. Most of the older ones were cast iron but anything is possible.

1. Probably not without making a real mess.
2. High nickel rod made for cast iron would likely work better.
3. Yes, preheating helps and be sure to weld in short passes then peen the weldment.
4. I welded a plate across the front of a broken ram and it's still going strong. I cut several slots so it was plug welded across the face in addition to along the edges.

You could also machine a replacement block and fasten it to the broken area with bolts. Welding is often not the only answer.

[781]

Have you tried calling Sid or Carrie at Little giant, Nebraska City< NE and ask them

[Nakedanvil - Grant Sarver]

Is it in the frame or the ram? A photo would really help, we will be able to advise you of a good repair if we have all the information. There are many options, but you need a really good repair for a highly stressed are like the dovetail. The best repairs on unknown materials use a lot of pre-heat, with cast iron that can mean red hot! Also, you can drill and tap holes and put a large number of studs in before welding. You just put bolts in tight and saw them off so they stick up a little.

Edited November 1, 2009 by nakedanvil

[chatchard]

If you want to find out if it is cast iron or steel you can try this.

1) drill a small hole if you can and check the chips. If they are iron they will not cut your fingers and they will break as you grind them between your fingers
2) Take a chisel and peel a cut off the material. If it is iron the chip will curl slightly then break. If it is steel it will be ductile and keep curling and leave a sharp hook.
3) If you have the piece of the metal in your hand drop it on the floor. Dull thud, iron, rings its steel.
4) Same rule for a hammer, hit the casting if its big enough, if the hammer blow is dead and doesnt bounce, its iron, if it bounces back its steel
5) Grind it and observe the spark. Dull red short spark, iron, long yellow with forks its steel.
6) Clean the part and handle it, does your hand still get dirty? That's the free carbon in the cast iron, steel will not make your hands dirty


To weld iron you want it good and hot. I usually go 650f minimum. Pure nickel rod if it is going to be machined, 50-70% Fe remainer nickel if no machining. Slow cool, no weave, multpass, small rod.
Cast steel, 250f preheat, fresh 7018 (just out of a box or an oven you dont want any moisture) Small rod, no weave.

Edited November 3, 2009 by chatchard

[David Einhorn]

So to summarize, there are too many unknown variables.
- It is very important to post a picture so that the folks on the forum can see the damage and where it is located.
- It is also important to identify the manufacturer and model to help identify the material used in making the damaged part.
- And most important it is crucial to identify whether it really is cast steel or cast iron. Cast steel (in my humble experience) I have welded with regular rod, while cast iron must be welded with nickel rod.

[pkrankow]

Does ductile (white) cast iron act the same as grey cast iron?

Phil

[ThomasPowers]

I usually think of white cast iron as chilled cast iron VERY HARD not like ductile at all!

[pkrankow]

Thomas, You are right, but not answering my poorly worded question. I looked up some stuff to word the question better.

Ductile cast iron is heat treated grey cast iron to make it ductile with spheriods of graphite instead of flakes.
White cast iron is either chilled or high alloy so there are carbides instead of free graphite. Chilled cast iron is heavy sections has a grey cast iron core, while high alloy cast iron will be white through and through.

Now to be more specific, chatchard listed some machining points on identifying cast iron vs steel. For white cast iron, chilled or alloy, would the results be similar as grey cast iron?

Also would drilling chilled white cast iron produce a black powder like chip?

Phil

castiron

[Nakedanvil - Grant Sarver]

Actually ductile iron is created in the melt by "inoculating" it with aluminum. It is ductile as soon as it is cast and "may be" heat treated depending on the alloy. Malleable iron is made by heat treating white cast iron for a long period. Chilled white cast is nearly impossible to drill, sounds like you're drilling grey cast to me.

And none of this matters! The frame and ram of a hammer will be either gray cast iron or cast steel.

[Hillbillysmith]

pics are needed so nobody tells you how to weld it one way, and it ends up being a part that we werent thinking of and you could possibly get seriously injured. its for your safety and the safety of those around you when you are using the machine.... if it happens to just be a plain jane casting spot that holds a part and not something that holds the ram, square it up with an angle grinder with a cut off wheel. cut a piece of mild steel to fit the spot and bevel the edges slightly where youre going to weld. preheat the area to approximatly 350-400 degrees (F) and use e-7018 welding only 1-2inches at a time and peen the weld after each little bead. and make sure the area stays close to the preheat temp. until finished then let it cool but not too fast.