4 inch 4 jaw chuck

[stevec]

(02-19-2013, 09:01 PM)dallen Wrote: poured the backing plate today, whats funny is the metal went in the furnace yellow as gold and came out of the mold looking a lot like copper and the stuff I used was all the same color and not a bit of copper in it.

I always thought bronze and/or brass were alloys containing copper?

[dallen]

they are but not in enough of the material to turn it from yellow to a copper tint when its been remelted. and the parts that I melted yesterday were not red brass there were swivel bearings out of a swivel joint that the mud line connects to on on a oil drilling rig, so they were some type of bearing bronze. I'm not too concerned with it just would like to understand why it turned red like it did. The red tint may have something to do with the fact that I pulled the part from the mold less then 10 minutes after pouring it, but it also did something that I've seen before which was that what I poured into the ingot mold turned very black on top but this is mostly from the hot molten metal oxidizing.

Anyway so far its machining ok, and I didn't have a lot of shrinkage on the part so the big Sprue and extra thick gate did what they were suppose to do which was feed the part till it stopped shrinking.

heres a shot of some of the bits laying on top of the furnace.

   

[EdK]

That's going to be one snazzy looking back-plate.

Ed

[dallen]

thanks for the compliment Ed, I just hope I get the thread in it right without screwing up, its metric, anyway you get the picture,

DA

[dallen]

this project is one that I guess you could say is going in the can, I messed up the threads and found that it was a lot cheaper to buy a backing plate already machined that only needed a skim cut to the face for 26.00 a lot easier then redoing the casting to make one with. So I bought one.