standard tables
Most tables designed for writing or dining should be 28" to 30" high (29" is common) with chair seats 11" to 13" lower. The higher the tabletop, the more uncomfortable and formal the table feels. Provide about 24" of leg room below the table (height from floor to bottom of table rail) and at least 12" for knee clearance (projection of table top beyond table leg).
on three of the boards, there was a problem: the bottom right coil seemed to be very insensitive. I think there was a cold connection with GND. i think while soldering I burnt the connection. I was able to correct one of them. I will see how to fix the other two tomorrow.