If you have more than one board, place the next board in the oven with a piece of the Temperature Marker in the location determined from above. Remove the PCB after the Temperature Marker melts, let cool and inspect the solder joints. Repeat the above step until all the boards are reflowed.
Turn Oven off.
Repair any solder defects with a solder iron. Use a fine tip on the solder iron and do not let the tip touch the body of the SMT parts. The solder iron temperature should be set as low as possible. A solder iron that is set to a high temperature can thermal shock SMT components.
NOTE: If the PCB has SMT components on both sides of the board, process the side with the smallest SMT components first. When processing the second side of the PCB, it has to be held off the oven shelf with standoffs. The SMT solder joints from the first reflow will be disturbed if placed directly on the oven shelf.
The IPC 610 is an industry SMT solder joint quality standard. It can be ordered from the Institute for Interconnecting and Packaging Electronic Circuits (IPC). Their address is:
2215 Sanders Road
Northbrook, Illinois 60062-6135
Tel (847) 509-9700