My first workbench has served me well but I have outgrown it. It is a 60" x 36" salvaged Ikea butcherblock (Beech) top on a 2x4-constructed base, with a tool cabinet underneath. However, it is time to upgrade. The main problems with the existing bench are:
1) The top isn't thick enough (~1-1/8") for hand tool work. It bounces too much and doesn't feel solid. Forget about chopping on it.
2) The top isn't and doesn't stay flat, making it useless as a reference or assembly surface. Though I've handplaned it flat several times, it goes out again within a month or so.
I've been reading bench books, drooling over bench hardware, planning a "real" workbench build for a while now. But I also came to the realization that building "the final" heirloom $$$ bench isn't in the cards right now for a number of reasons. Financially difficult, but perhaps even more importantly, a few space constraints that would require design compromises I'm not willing to make on my "final" bench. For example, my workbench is also my tablesaw's outfeed, and that's not changing while I'm in this space. And while we'll be here for a few more years at least, there's a good chance we'll be in a different home in 5-10 years. One with a larger shop space and where I'll feel more at ease about designing and undertaking building the bench I've been dreaming about.
This means that for my "second-to-last" workbench, I'm going to try to keep costs to a minimum while still getting a workbench "build" experience. The design will be a standard modern classic - front and twin end vises, probably 60" x 30" x 3.5-4" top, recycling the tool cabinet for underneath. But the priorities this time are a dead-flat, thick wood top, and making it look a bit nicer than the one I have (e.g. dovetailed end caps). I'll re-do the base simply because it's ugly (I didn't have any milling equipment when I made it).
All this brings me to my choice for top material: Doug Fir vs. poplar. I've read several threads about using DF for workbench tops via careful selection of material, either 4x4 or 2x12. Alternatively, I can get properly milled FAS 8/4 poplar at around $2.30/bdft (in contrast other acceptable woods such as soft maple would be around $4/bdft and probably push my wood costs further than I'm willing for "2nd-to-last" bench). Both woods are a little softer than ideal, getting easily dented/scratched, but I like the way poplar machines and works a little better. The greenish hue isn't my favorite for looks. The DF would be cheaper probably, but board selection would be time-consuming, lots of waste, and it may be hard to get perfectly dry material, resulting in continuous movement over time. Regardless of which wood I'd use for the bulk of the top, I'd use something harder for end caps, and edges.
Thoughts?