For my third project I built my brother-in-law the Fancy X Farmhouse table cut down to a size suitable for him and his girlfriend. When I read through the comments it seemed like alot of people had the same question: How do I attach the top?!?!?! As this was going to be used for an indoor dining table I didnt want to screw through the top if I didnt have to and I didnt want to use metal bracketry eithery. What I did required 4 inch screws and a 5/8 drill bit. Ive attached pictures to show where I placed the wood suport pieces. Two screws went through the top cross beam (connecting the two leg ends) into the center support piece and I put a total of 2 screws each through the sides of the two longer support pieces and into the top board of the legs. I used a 5/8 bit to drill about an inch (very rough estimate and essentially to countersink the screws an inch deep) into the 3.5 inch width of the 2x4s and then a smaller drill to pre-drill holes for the 4 inch screws. This allowed the head of the screws to sit about an inch into the wood and the threaded portion of the screw to dig deep enough into the second board without going through it. Overall it holds great and there are no visible screw heads on the top of the table!
FYI This technique DOES require aligning the cross beam with the top of the second 2x4 rather than the top 2x4 because you want to save enoughg room the support pieces. (See pictures)