In this step I will glue up the top plate. I am using Sitka Spruce. It is Grade AAAA so it has some fine grain in it with a little, what is referred to as, bear claw grain pattern.
I bought the plates from a luthier supplier so they come sized and thicknessed to 3.5mm. There is not much to work with here as I will take them down to just under 3mm.
For now though I will only put a jointed edge on one side with my jointer, clean up the edge with a straight edge sanding and then proceed to the glue-up.
For the first step I tape the ends and put them through the jointer together in their bookmatch form (not pictured). This is something I always do when doing any bookmatch work.
I then clamp a board to my bench with one plate trailing over the edge. You can do two plates at once as the spruce is quite soft and sands quickly. If you do one at a time make sure you keep the plates in the bookmatch formation.
Take a straight edge, apply a strip of 180 or 240 grit sand paper to the edge and rake lengthwise, sanding along the plate edge. (I buy rolls of 3M sticky-on-one-side sand paper.)
Keep the level flat to the bench surface. When finished hold up to light and check for any gaps and quality of joint.
This is a standard butt joint so I put the two plates together, raised in the center with a 6mm thick board and some wax paper.
With the plates in position screw some blocks down to the work board keeping the plates snug together.
Apply glue to the jointed edge, pull out your stick in the center and gently press the two plates flat down onto the work board. Lay some more wax paper over top and clamp it down with some long reach clamps.
Keep it in the clamps for a few hours. I like to wait until the next day to do any work on this as the butt joint is only 3.5mm thick. So give the glue a full day to cure.