Just bought some M6 JIS screws from Mr. Megapack on eBay .. hoping to chop down to various sizes... 50mm ones are OK for this as fully threaded but 75mm ones (well listed as 75mm under head but actually measure 80mm under head) are only partially threaded ... plus it looks like a rolled thread with the unthreaded portion not suitable for re- threading properly with a die, as the unthreaded diameter looks too small..... and before you pick up on it Trigger ... I am replating the cut ends of any I chop shorter, promise