Ideal heights for table with skirt and bench
Hi - I'm working on a sofa table (a table that sits behind a sofa) along with a bench that would slide underneath the table such that somebody can sit at it. I want to put a few drawers in the skirt of the table. I've included a Sketchup drawing of my current plans. However, I am fairly confident that the dimensions need some work still.
The back of my couch sits at 28", though the cushions on it go to about 32" or so. So my initial plan was for the table to sit at 28". However, it looks like 30" is more standard for a table height. Further, it looks like 31-33" is more common for couch back heights. Since I suspect I'll be in need of a new couch in the next few years, I think it would make sense to put the table at 30" tall. Now - for the bench - It seems that 17-19" is standard height for benches. I'm thinking I'll aim for the bottom of that - 17", to allow for a cushion to go on there (maybe raising height of person to 18" once cushion flattens out a bit). Are there standard bench cushion sizes?
Finally - I still need to figure out how big the apron, and thus drawers, need to be. My plan is to have the drawer fronts flush with the apron. Further, to make the drawer fronts I plan on ripping my apron into three pieces. Let's say it's a 6" apron with a 4" drawer, I would rip it into a 1", 4", and another 1" piece. Then I can cut out the drawer fronts from the 4" piece and glue what remains back together, so that the grain of the wood will be continuous even through the drawer fronts.
To figure out the height of the apron - I measured myself while sitting on a flat surface. My legs look to be about 5.5" thick when sitting on a flat surface at their thickest - so 6" would allow me 1/2" of wiggle room. 7" would be better at 1.5" wiggle room. So the lowest the apron is allowed, with m ~18" bench, is 18+6=24". 25" would be better. At 30" tall with a 3/4" top that means the skirt can be 4.25-5.25 tall.
Finally - the thing that makes me the most nervous is the dovetail joints for the drawers. I understand that there are preferable heights for drawers when doing blind dovetails. I read in the Porter Cable dovetail jig manual that you ideally want your drawer to be 1.25, 2.25, 3.25, 4.25, etc tall for the optimal dovetail. Is that true for all jigs or just Porter cable? I have access to a few jigs but need to confirm which. If that is the standard rule I think I would make my drawer 3.25" tall, and then allow for about 3/4" wood both below and above the face on the apron, giving me 4.75" tall apron.
Do these numbers all seem reasonable? Any comments on optimal dovetailed drawer heights? Sorry for writing so much - just want to make sure I didn't miss anything!