Commuters who use the Sagamore Bridge may want to leave a little earlier for work than usual this week, as a scheduled paint job set to begin Monday will close a lane. The US Army Corps of Engineers plans to close one lane on the bridge from 8 a.m. to 4:30 p.m. from Monday through Friday, leaving open two lanes going on to the Cape and one lay traveling off the Cape. Work will continue during the same times the following week from April 16 to April 19. All lanes will be open overnight and on Patriots Day, according to the corps’ website. The project involves blast cleaning the 1,408-foot steel bridge to its bare metal before it can be repainted. To learn of any changes during the maintenance schedule, commuters can sign up for bridge work alert e-mails by sending an e-mail to CapeCodCanalBridges@usace.army.mil with the subject “bridge work alerts.”Sarah N. Mattero can be reached at email@example.com.