stained 356 castings from foundry
stained 356 castings from foundry
(OP)
Well, either from the foundry or the machine shop. It starts out as a very light discolorization on the casting like something was spilled on it. After going through powder coating and baking of the powder coat the stain turns dark brown and bleeds through the powder coat paint.
The machine shop says that's the way they got them. The foundry says there's no way the parts were stained while they had them.
The parts are made from a permanent mold. The foundry heat treats them and "wheelabrates" them. They go direct from the foundry to the machine shop so I don't get a chance to see them until after they are machined. It just started happening on the last shipment of 300 parts. Now it's happening again on the latest group of 300 parts.
There's no problem with the sand castings produced from this foundry (just this permanent molded part) or from any of the other parts machined at this machine shop. So my question is, have you ever seen stained parts come from the foundry?
The machine shop says that's the way they got them. The foundry says there's no way the parts were stained while they had them.
The parts are made from a permanent mold. The foundry heat treats them and "wheelabrates" them. They go direct from the foundry to the machine shop so I don't get a chance to see them until after they are machined. It just started happening on the last shipment of 300 parts. Now it's happening again on the latest group of 300 parts.
There's no problem with the sand castings produced from this foundry (just this permanent molded part) or from any of the other parts machined at this machine shop. So my question is, have you ever seen stained parts come from the foundry?





RE: stained 356 castings from foundry
RE: stained 356 castings from foundry
Yes, the castings are heat treated by the foundry prior to machining.
I tried to upload a picture but there were errors. I'll try again later on.
RE: stained 356 castings from foundry
RE: stained 356 castings from foundry
RE: stained 356 castings from foundry
The machinist machines several of our other 356 castings (sand castings) and there's no stain problems with them. He says he uses the same coolant and machines on each of the parts.
RE: stained 356 castings from foundry
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RE: stained 356 castings from foundry
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RE: stained 356 castings from foundry