I have three plastic tubes for storage. Two have lids and one that does not. It is a simple single step lid, flat on the top and bottom with a top step to keep the lid from falling into the tube. Over the years I would just put a baggie with a rubber band to cover the one that was missing the lid. One day it just irritated me about the lid for some reason and I had nothing pressing to do. I thought, “This is dumb. I have casting sand, cope and drag, cast pistons to melt, and the set up 30’ from me, plus a cap for a pattern.” Grabbed the ‘too tight’ cap off of one of them and in 30 minutes had the metal melting, pattern ready and was well on my way. I did not put my glasses on to do any of the process. The first pounding and pulling the pattern had the inner edge/step break out and I presumed I have not packed it good enough. Redid it and had some breakage on the edge again, but acceptable to me. I should have put my glasses on and really checked out why, but then again it was ‘just a lid’. Cast it and it came out fine, but the edge where the sand broke out was clearly visible. NOW I put my glasses on to take a look to see why this happened. Whoever turned the cap (solid aluminum) I used for the pattern had UNDERCUT about a 1/16th” groove in the inner edge! On inspection the other cap I could have used did not have the undercut. Doh! No wonder it broke out! I should have put on my glasses!
Oh boy. I will state I did it fast, did no clean up, bla, bla bla. Basically it is a bit ugly, but here are some pictures! The three are; IF I decide to do another, 'Lost Foam' on the left, the one I sand cast in the middle, and the pattern cap is on the right. The other picture is the pattern one showing the undercut under the top.
