This is a small trivet I cast several of, 36 so far. I have noticed a small crack in this area a few times but nothing that prevented the trivet from being used. While cleaning up this one it came apart. The members are small (less than 1/4") and I have to pour it hot (1550F and above) to get a complete fill. After this failure I had to think back. I had poured two that morning, about 1570F and two the next morning, a little hotter. I'm using scrap, specifically an old TV antenna for a lot of this one, and maybe some window frame material. I wasn't sure whether it was the metallurgy, it was pouring practice, or other. I repoured this morning at over 1,600F with no cracks. I always assumed hot tears occurred from pouring too hot. on this pattern I'm assuming the small wheel spokes cooled first and the large feeder tried to pull material from the joint. I don't know why hotter worked and am looking for comments. I can't pour much cooler and still fill. In this picture MHR has been desprued and AFL has not. Gates are 3/16" thick, runners are about 1/2" wide by 3/4" deep, break is between the spoke between the A and F, or M and H.