I should be ready to start milling the mounting blocks for the ballscrews for my new (old) knee mill pretty soon so I need to pickup some suitable stock. I'm guessing it would be better to use steel not aluminum for these mounting blocks?
Assuming steel with an emphasis on easy to machine what grades should I be checking for stock at the local metal pros supplier?
P20 is another one to look for. Nice easy to find and a dream to machine. It's a Mold steel, so you might be able to buy suitable chunks from local shops at cheaper "drop" prices.
P20 is another one to look for. Nice easy to find and a dream to machine. It's a Mold steel, so you might be able to buy suitable chunks from local shops at cheaper "drop" prices.
Funny p20 "drop" story. Last fall we got a job from one of our "eccentric" customers. A few components from a larger assembly. Large stuff, from simple burned plates of a36, and structural angle. Nothing too crazy this time. Last minute he decides to "change the spec" of one of the angles because he decided the material wasn't strong enough....P20 was the new material it needed to be made from. A 6x8x40"x3/4" wall "angle iron" made from p20...... Finding the original spec angle was hard enough, but we did track some down in California (Oregon? somewhere on the west coast anyway, I can't remember now), and they were willing to cut us a short piece from a full stick. Now we had to call them back to cancel.....
Long story short, I whittled a p20 angle from a solid block and instead of turning it all into chips, I did my best with what we had to chunk it out in 2 pieces. One about 4x4, and the other 1.25x3. My Boss has always been good about letting us pick from the drops and scrap bin for material for personal projects, little stuff is fair game, but I've always asked over anything bigger than about 4" cubed. Most times it's "just take it", other times it's "bring in a box of doughnuts for the boys" etc. I've never abused it, but it's been pretty handy over the years. Some guys take it a bit too far sometimes, but I did joke about taking this chunk of p20 home though..... "Hey can you grab that end, and help me get this in my car".....lol.
It's all gone now, as I've built a couple jobs from it since.
Anyway sorry to hijack your thread. Just thought a backstory about why shops have drops laying around might be entertaining to some.....
"Hey can you grab that end, and help me get this in my car".....lol. 
