Before joining the top to the base, loosen the bolts and screws on the lower stretchers to create a little play in the leg posts. Align the top notches with the leg posts and tap the top into place with a hammer and piece of scrap wood, working evenly around the table until all leg posts are level with the tabletop. Tighten the lower stretchers and you’re done. A hefty thanks to Doug Merrill for this weighty idea.
A woodworker's workbench isn't a table, it's a work-holding system. It's not something you set things on top of, it's a tool that holds your work. Where a worktable might have a machinist's vise bolted to its top, a woodworker's bench is built to accommodate a number of different workholding mechanisms, such as bench dogs, planing stops, hold fasts, or board jacks, and will usually have one more woodworker's vises integrated into its structure.
Regardless of which type of screw you use, you'll need to flip the panel and use a countersink drill to on all of the exit holes. Drilling MDF leaves bumps, the countersink bit will remove them, and will create a little bit of space for material drawn up by the screw from the second sheet of MDF. You want to remove anything that might keep the two panels from mating up flat. I set a block plane to a very shallow bite and ran it over what was left of the bumps and over the edges. The edges of MDF can be bulged by by sawing or just by handling, and you want to knock that down.
We have more than sixty years of excellence (1956-present) with an annual enrollment of more than 1,000 students in over 35 different classes.  The Palomar College Cabinet and Furniture Technology program offers the most comprehensive woodworking career curriculum in the nation. Utilizing three fully-equipped shops, our 2 full-time and 20 part-time instructors provide a breadth of courses and depth of expertise impossible to obtain in smaller programs.
If you remember, when drilling the MDF I finished the holes from the other side using a Forstner bit. It made for a clean hole, but the positioning wasn't as precise as I really wanted. So for this, I decided to clamp a length of scrap MDF to the back side, and to drill straight through. My Forstner bits were too short, so I bought an extender. And then I found that the spade bits I was using gave a cleaner exit hole. Whooda thunk?
2 - use a plunge router with a bottom bearing cuter bit such as this from rockler: .... I thought to use the short one as I plunge it directly downward in the centre of the hole until the bearing reaches within the tabletop hole. I suppose one could use a long one, but the stubbiness seemed more practical (the big bearing ensured accuracy?)
So drill the benchdog holes through the MDF layer. Begin by laying out their positions. You'll want these to be precise, so that the distances between the holes are consistent. The vises you are using will constrain your benchdog spacing. My front vise worked most naturally with two rows of holes four inches apart, my end vise with two pairs of rows, with four inches between the rows and eight inches between the pairs. Because of this, I decided on a 4" by 4" pattern.
Students who are interested in woodworking, either as a career or a hobby, can find classes through certificate and vocational degree programs. Furniture making and opportunities for wood sculpture can also be found at schools that offer studio art programs. In California, a wide range of programs in the field are available, including individuals classes as well as formal educational programs. While degree programs include general education programs, all woodworking programs focus primarily on the development of hands-on skills with respect to safety measures.

This class is open to novice woodworkers and to more experienced woodworkers who would like to broaden (or simplify) their approach to woodworking. What do we mean by novice? We think it means you are a person who has decided to commit to learning new skills; to growing a passion for the craft of working with wood; and has a strong sense of the limitations of your own knowledge.
The last thing is to semi-permanently attach the bolts for the vises. Given the amount of work necessary to get to the bolt heads, once the top is joined, I had intended to tighten them up so they wouldn't spin, and lock them that way with blue Loctite. (That's the strongest non-permanent grade.) That didn't work. What I found was that the bottoms of the countersinks weren't quite flat, and when I tightened the nuts down that far, the ends of the bolts would be pulled far enough out of alignment that the vise bases would no longer fit. In order for the vises to fit over the bolts, I had to leave the nuts loose enough that the bolts had a bit of wiggle - which meant that they were almost loose enough for the bolts to spin. So I put Loctite on the nuts, to keep them from unscrewing, and filled the countersinks with Liquid Nails, in hopes of keeping the bolts from spinning. I considered using epoxy, or a metal-epoxy mix like JB Weld, but I didn't have enough of either on hand. It seems to be working for now, though the real test won't be until I have to take the vises off.
Anyway, I'd like to know if I'll be able to keep (EDIT: and use) all my tools out there (current and planned) without having the shed become a rust-bucket for the tools and machinery inside. I'll have a 10" contractor's saw out there along with a drill press, a sanding belt, a router & router table, and lots and lots of old tools that I inherited from my Granddad years ago. I live in the Seattle area, so it rains A LOT. But I'm hoping that with the proper ventilation I can keep the tools in the shed dry.